• LDA and RDA – Most common in dairy cattle within one month of parturition or prepartum. Due to hypocalcemia resulting in abomosal atony. Leads to metabolic alkalosis, hypochloremia, hypokalemia due to sequestration of acid, chlorine and potassium in abomasum. Left 5-10x more common than right. Left-sided ping between ribs 9-13. Normal TPR. Anorexia, decreased production, ketosis. Diarrhea is poor px sign. Treatment - roll cow, but recurrence likely. Surgical correction with rt flank pyloric omentopexy or rt paramedian abomasopexy, combined lt flank & rt paramedian abomasopexy. RDA can become AV. Recent parturition, partial anorexia, decreased milk production suggest displacement.
• Abomasal volvulus – Dairy cows near parturition w/ sudden drop in milk production. Usually counterclockwise from rear. Very sick, clinical signs more severe dt vascular compromise. Right sided ping, palpable. Treatment is surgery. Poor prognosis. Tachycardia present, area ping maybe btwn ribs 8-13, weakness, toxemia, dehydration. Recumbent
• within 48-72 hrs.
• Abomasal ulcers - Most common in high-producing dairy cows in first 6 weeks of production. Stress decreases protective prostaglandins. Ulceration at the ventral portion of the fundic region of the greater curvature. See melena, anorexia, occult blood, abdominal pain. LSA is significant cause of bleeding ulcers in older cattle. Bleeding ulcers don’t perforate and perforating ulcers (seen in calves) don’t bleed.
• Abomasal impaction - Pregnant beef cattle in winter with poor quality feed.
• Left Ping = LDA, pneumoperitoneum, atonic rumen.
• Right Ping = Spiral colon, rectum/colon, RDA, RAV (palpable).
• Tx: = displacement: ca2+ borogluconate SC or ca2+ gels POrestore normal abomasal motility
o provide H20, NaCl blockrestore electrolytes, fluids
o more severe cases:7.2% NaCl, 5 ml/kg IV over 5 min
• Px:=following calving: feed total mixed ration, avoid rapid dietary changes, maintain roughage in diet, avoid postparturient hypocalcemia
• Cattle - Herd problem: IBR, BVD, brucellosis, leptospirosis, campylobacteriosis, trichomoniasis, anaplasmosis, ureaplasmas, mycoplasmas. Sporadic: Mycotic (Aspergillus, Mucor spp). Reach uterus hematogenously, cause late term abortion. Fetus not affected or may have ringworm lesions; placenta severely affected with necrosis of cotyledons. Dx via culture of fetal tissue. Neospora caninum; common in dairy cattle, sporadic abortions, b/w 4-6 mo gestation, dog definitive host, fetus usually autolyzed, px: prevent dog fecal contamination of feed. Arcanobacterium (Actinomyces) pyogenes; sporadic abortion, gains entry to bloodstreamendometritis, placentitis; fetus autolyzed Also Listeria, Haemophilus, Corynebacterium pyogenes, Staphylococcus, bluetonque, Ureaplasma diversum; normal inhabitant vagina, prepuce cattle; abortions single, usually 3rd trimester, well preserved, (-) lesions in fetus, isolate from lungs, placenta, abomasal contents. Nitrates, lupine, locoweed, mycotoxins.
• Mares - Most common infectious cause of abortion in horses is Equine Herpes 1, last trimester. Equine viral arteritis less frequent. Vax available for both diseases. Sporadic abortion from Streptococcus zooepidemicus, Escherichic coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Rhodococcus equi, Actinobacillus equuli. These infections occur through ascending infection via the cervix. Twin pregnancies often result in abortion. Crush the smallest embryo at day 22-25 after confirmation of pregnancy.
• Sheep - Most common cause of abortion is campylobacteriosis. Campylobacteriosis - Infection via ingestion of organisms. Late-term abortion of edematous fetus; liver with gray necrotic foci. Carrier sheep shed organisms in feces, uterine discharges, aborted fetuses. Culture and ID organism in fetal abomasal fluid and liver. Vaccinate ewes at breeding; booster at second month gestation. Toxoplasma gondii – protozoan; life cycle is completed in the cat. Abortion and still births in sheep, pigs, and goats. White foci in cotyledons, leukoencephalomalacia. Chlamydia psittaci (Enzootic Abortion of Ewes) – late-term abortion. Exposure via ingestion, inhalation or venereal. Fetus well-preserved or mummified. Placentitis most consistent finding. Leptospirosis - late-term abortions. Listeriosis - late-term abortion, birth of weak lambs. Slight to marked autolysis of fetus, fluid in serous cavities, necrotic foci in liver, lung and spleen. Erosions in abomasal mucosa. CNS deficits. Man can be affected. Akabane virus disease – arthrogryposis, hydrancephaly. Border disease (pestivirus); abortion any stage: fetus undersized, tremors, hairy coat (hairy shaker lambs); no vaccines. Cache Valley Virus: mosquito transmitted: stillborn lambs, live birthsCNS, musculoskeletal abnormalities; hydrancephaly, hydrocephalus, cerebral & cerebellar hypoplasia, arthrogryposis, scoliosis, torticollis, hypoplasia of skeletal muscles, dx via Abs in precolostral serum or body fluids; no vaxs
• Pigs – Vaccinations: parvovirus, pseudorabies, enterovirus, brucellosis, leptospirosis can affect reproductive performance. Vaccinate sows and gilts against leptospirosis, parvovirus and erysipelas. Also permit >21 day exposure to herd before breeding to allow natural exposure to endemic herd pathogens including parvovirus and enteroviruses that can cause reproductive failure. Parvovirus - Early fetal resorption, reduced litter size, mummies. Due to persistence of maternal immunity in gilts until sexual maturity, exposure at breeding time. Pseudorabies - Abortion, stillbirths, mummies, weak pigs. Also fever, respiratory signs, nervous signs. Brucellosis - Venereal. Leptospirosis – L. interrogans one of most common causes of reproductive failure. L. pomona is late term abortion. L. bratislava commonly id in serologic surveys in midwest US but NOT affected w/ abortion or repro problems. Porcine Reproductive and Respiratory Syndrome (PRRS): arterivirus, most imp dz pigs US, >90 d gestation, abort end gestation; sows anoretic, fever; litter weak infected pigs & uninfected pigs develop respiratory dx; hemorrhage umbilical cord only lesion fetus. Vax available. Japanese B Encephalitis Virus: ZOONOTIC; arthropod-borne;reproductive failure pigs & humans. Litter:mummies, stillborn, weak pigs;hydrocephalus, SQ edema common lesion. Severe hyperkalemia-à bradycardia; ECG alterations
• Cow – PGF2 up to 4th month. Months 5-8 PGF2 & Dexamethasone combination. 75% have retained placentas. 0-14 days pre-term, calves born with normal viability and normal blood IgG.
• Mare - PG for abortion only. May need double dose or repeated treatment at 48 hour intervals after 4th month. Douching of uterus also works at any stage of pregnancy. Oxytocin for live foal only after cervix has begun to relax and colostrum is in udder.
• Small animal - Not safe. PGF2 can be used after day 40. Dexamethasone 10 days produces fetal death and resorption.
• caused by F. necrophorum, G-, obligate, anerobic,
• predisposed to rumenitis
• rumenitis caused by incr carbohyd in feed—incr ruminal acidity—colonization of bacteria
• superficial necrosis—bacterial emboli invade hepatic portal syst—liver—microabscesses
• feedlot: changed roughage to finishing ration
• few clin signs: may see grunting, other signs pain
• decr feed efficiency, wt gain
• sequelae:peritonitis, sudden death:rupture abscess into hepatic blood vessels
• rupture hepatic vein:thromboembolic dz, endocarditis, pulmonary thromboembolism
• hemoptysis, epistaxis, death
• dz:ultrasound, antemortem:serum sialic acid
• control:prevent ruminal acidosis;method of feed, use buffers, diet composition
• incr roughage diet, multiple feedings—incr buffers in rumen, decr ruminal acidity
• tx: virginiamycin fed at 25 g/ton of feed or chlortetracycline fed continuously at 70 mg/head/day during the finishing period, significantly reduce the number of liver abscesses and increase feed efficiency and weight gain, little effect on prevalence of ruminal lesions
Phenothiazine tranquilizer. Block release and uptake of dopamine in the CNS. Also has anticholinergic, antihistaminic, antispasmodic and alpha-adrenergic blocking effects. Depresses RAS. Administer atropine to counteract bradycardic effects.
• Adverse effects - Precipitates seizures. RR, arterial BP, CVP, bradycardia, sinoatrial arrest. Bradycardia negated by physiological response to decreased BP. Causes extrusion of penis in male large animals. No analgesic effects.
• Positive effects - Antidysrhythmic effects. Inhibit arrhythmias induced by ultra-short barbiturates, halothane, epinephrine. Reduces halothane-induced malignant hyperthermia in pigs.
• Contraindications - Decrease dose in animals with hepatic dysfunction, cardiac disease. Contraindicated in patients with hypovolemia, shock, tetanus, strychnine.
Acetabular fractures – If there is no displacement, fractures treated conservatively with Ehmer sling and restricted activity. Bone plates and screws used for internal fixation.
Acetaminophen poisoning - Tylenol.
• Clinical signs - Hemolytic anemia, methemoglobinemia. Dark-colored urine. Icterus, facial edema, lethargy. The liver is the primary site of toxicity.
• Clin path - Heinz body anemia, hemolysis, hemoglobinuria.
• Therapy - N-acetylcysteine (Mucomist).
• Mechanism: cats lack glucuronyl transferase; unable to metabolize
Acetonemia (cattle) - result of a –ve energy balance in the 6 wk after parturition. Incidence highest 3rd, 4th wks of lactation if cows improperly fed, conditioned during dry period. lactating dairy cows, fed for high milk production. Blood glucose drops—hypoglycemia—gluconeogenesis—ketone bodies.
CS : ↓ in feed intake, ↓in milk prod, lethargy, firm-mucus covered stools. May see marked wt loss, pica, ACETONE ODOR TO BREATH, frenzy, aggression, bellowing, circling, staggering, falling.
Predisposing conditions: ROP, metritis, mastitis, displaced abomasa, fatty livers, environmental stresses, faulty nutrition, and mismanagement.
Lesions: carcass is thin, malnourished with little body fat, indicative of starvation; liver, pale yellow and may be soft and friable. h/o parturition, bizarre behavior. Rothera’s test for ketone bodies: on milk more definitive dx (<50 mg/dl); bld glc
--levels normal 40-60 mg/dL drop to below 25 mg/dL in clinical ketosis
-DDX: hypocalcemia, retained fetal membranes, metritis, indigestion, abomasal displacement,
traumatic reticulitis, poisoning, pyelonephritis, listeriosis, and rabies.
-TX: IV administration of 500 mL of 50% glucose and IM administration of the glucocorticoid
Propylene glycol (225 g, b.i.d. for 2 days, followed by 100 g daily for 2 days)
--properly condition during late lactation and dry period
--body score should be 3.5/5.0
--2 wks prior to parturition-sm amt concentrate, gradually incr to 1 lb/150 lb body wt. daily
--DON’T OVERFEED after parturition
--rations containing 16-18% crude protein and 19-21% fiber
--eliminate predisposing factors
Acrodermatitis – Lethal familial zinc deficiency in white bull terriers. Retarded growth, progressive, acral, hyperkeratotic dermatitis, pustular dermatits at mucocutaneous jxns. Death by 2 yrs of age. Don’t respond to Zn therapy
Acute Abdomen – Syndrome. Acute presentation, showing systemic signs, abdomen painful, distended, V/D, weakness. Major categories are bacterial sepsis, obstruction/perforation, ischemia/thrombosis. Fundamental question is surgical or medical tx reqd. W/ septic peritonitis, the solution to polution is dilution – exploratory and lavage. See GDV and pancreatitis for others.
Addison's Disease – Hypoadrenocorticism. Immune-mediated or iatrogenic adrenocortical insufficiency leads to deficiency of glucocorticoids and mineralocorticoids. Seen in young to middle-aged dogs, occasionally horses. Familial in standard poodles (?). Lack of aldosterone secretion results in impaired ability to conserve Na+ and excrete K+. Leads to hyponatremia and hyperkalemia (Na:K < 25:1).
• Clinical signs - Hyponatremia leads to hypotension, CO, hypovolemia. Results in prerenal azotemia. Severe hyperkalemia-bradycardia; ECG changes. Lack of cortisol secretion can lead to GI signs, lethargy, and impaired stress response. Normocytic, normochromic anemia. Absolute eosinophilia. Hypoglycemia due to glucose production (glucocorticoid deficiency). Occasional hypercalcemia.
• Ddx – Whipworm infection, renal failure, acute pancreatitis, toxin.
• Diagnosis - ACTH stimulation test.
• Treatment – Fluid replacement, electrolyte assessment. Florinef (Fludrocortisone acetate) or DOCP (Desoxycorticosterone pivalate). Prednisone if necessary.
ADH – Antidiuretic Hormone. Suppresses excretion of urine. Has specific effect on the epithelial cells of the renal tubules. Stimulates the resorption of water, resulting in concentration of urine.
Adrenal Glands – Endocrine gland. Adrenal cortex - Three zones. Zona glomerulosa (outer) secretes mineralocorticoids. Zona fasciculata (middle) layer secretes glucocorticoids. Zona reticularis (inner) secretes sex steroids. Accessory cortical tissue seen as small nodules in aged dogs is common and nonfunctional. Adrenal Medulla – Modified sympathetic nervous system ganglion. Secretes epinephrine and norepinephrine. Important role in response to stress or hypoglycemia. Tumor of adrenal medulla is pheochromocytoma, which may secrete either hormone.
• Mineralocorticoids - Aldosterone regulates ion transport of epithelial cells, resulting in excretion of K+ and conservation of Na+.
• Glucocorticoids - Regulate carbohydrate, protein and lipid metabolism resulting in sparing of glucose and lipolysis. Glucocorticoids suppress inflammatory and immunologic responses. Can have negative effect on wound healing due to inhibition of fibroblast proliferation and collagen synthesis.
• Sex hormones - Progesterone, estrogens, and androgens.
--Aegyptianellosis: acute, tick-borne, febrile disease caused by Aegyptianella spp
--rickettsia, family Anaplasmataceae
--variety of avian spp
--vector: Argas spp
--bloodborne dz; “signet ring” shaped organism or oval, lateral to nucleus rbc
--most common in tropics & subtropics—can be found in wild turkeys in Texas
--clin symp-ruffled feathers, anorexia, droopiness, diarrhea, fever, jaundice
--Anemia, enlargement of the liver and spleen, enlarged discolored kidneys, and pinpoint
--tx:tetracycline, doxycycline & tick control
Aelurostrongylus abstrusus - Cat lungworm. Life cycle includes snail first host; frog, lizard, bird or rodent vector encysted larvae. Cat eats transport host, larvae migrate from stomach to lungs and embed in lung tissues. Eggs form nodules in alveolar ducts, larvae hatch, coughed up, swallowed and passed in feces. Larvae in feces have dorsally spined tails. Causes coughing, dyspnea. Treatment is levamisole. 9th Edition Merck, tx: Fenbendazole 50 mg/kg PO BID 10-14 d or ivermectin 400 microg/kg SQ, once
African Swine Fever – Iridovirus. Highly contagious viral disease that resembles hog cholera and is therefore REPORTABLE. Eradicated from western hemisphere. Replicates in RE cells, found in all fluids and tissues. No vaccine. Ornithodoros ticks are vectors. Oronasal exposure. Survivors carriers for life. Clinical signs include fever, vomiting, diarrhea, eye discharge, abortion, death. Hemorrhage of lymph nodes, renal cortex, splenomegaly (bigger than in hog cholera). Excessive pleural, pericardial and peritoneal fluids.
-hereditary, seen in heifers
-imbalance of hormones control udder development, lactation
-maybe assoc with fibrosis of mammary gland, grazing endophyte-infested fescue
-tx; not effective
Air Sacculitis – Mycoplasma gallisepticum. Causes respiratory tract infection in chickens. High rate of carcass condemnation. Caseous exudate. Clin signs: marked rales, coughing and/or sneezing, nasal discharge. More serious in turkeys: swelling paranasal sinuses. Tx: Ab in water 5-7 d: tiamulin, tylosin, erythromycin, enrofloxacin, spectinomycin
Control: maintain seronegative flock
--Air Sac Mite: Kytodites nudus; small mite;”white spots” on the bronchi, lungs, air sacs,
abdominal organs of chickens, turkeys, pheasants, pigeons, and mallards
--transmissbile btwn birds
--route of transmission unknown
--larval & 2 lymph stage cycle
--clin signs: none to weakness, weight loss, pneumonia, peritonitis, obstruction of respiratory
passages, and death
--tx:ivermectin, pyrethrin/piperonyl butoxide spray, dichlorvos pest strip
Aldosterone - The main mineralocorticoid hormone secreted by the adrenal cortex. Regulates electrolyte and water balance by promoting retention of Na+ and the excretion of K+. Retention of water induces an increase in plasma volume and an increase in blood pressure. Secretion of aldosterone is stimulated by angiotensin II.
Aleutian Disease - Parvoviral infection of mink resulting in immune complex formation and deposition. Clin signs: poor reproduction, wt loss, oral/GI bleeding, renal failure, uremia. Control: test/slaughter; No vaccine.
Alimentary Lymphosarcoma – Most have normal or peripheral lymphocytes. “Nonresponsive IBD”. Can be diffuse or multinodular. Dx w/ full thickness biopsy. Very difficult to treat.
Alkalosis - HCO3, TCO2, hyperventilation causes alkalosis. Cow saliva rich in HCO3 (horse saliva rich in Cl-).
Amyloidosis - Consists of pleated sheets of amino acids, refractory to enzymatic breakdown. Two major amyloid proteins. AA released from hepatocytes due to chronic infection. AL composed of partially degraded immunoglobulin light chains produced by malignant plasma cells. Disease caused by displacement of normal cells with amyloid deposits, mainly liver, spleen, brain and kidneys.
Anal Sac Disease – Hematochezia. Chronic bright red blood w/ normal stools.
Anaplasmosis – Anaplasma marginale. Rickettsia located in the stroma of RBC. Disease of ruminants. Transmission through contamination with infected blood via ticks (Boophilus, Dermacentor), horse flies, stable flies, mechanical transfer of blood (vax, dehorn, etc). Fomites. Carriers maintain disease in a herd. More severe in adult cattle; lifelong resistance if exposed young.
• Clinical signs - Depression, inappetence, fever, decreased production, marked icterus. Anemia leading to hypoxemia. No hemoglobinuria.
• Diagnosis - Suspect in mature cattle showing anemia without hemoglobinuria. Blood smear, see anisocytosis, presence of agent. Serology.
• Treatment – Tetracycline. LA200. Do not stress patients, may die. Insect control.
• Vax – May cause neonatal isoerythrolysis.
Ancylostoma caninum – Canine hookworm. See hookworms.
Anemia – CRC = % reticulocytes X patient PCV/normal PCV (45 in dog, 37 in cat). Regenerative if > than 1% in dog or 0.5% in cat. Horses have no peripherally circulating reticulocytes.
• Regenerative Anemia – Macrocytic, normochromic, nRBCs. Regenerative response take 2-5 days.
• Hemolysis – Intravascular = RBC destruction w/in blood vessels and loss of Hgb from cells. Often severly ill w/ weakness, fever, icterus, Hgbemia, Hbguria. More aggressive therapy, worse px. Extravascular = RBCs lysed following phagocytosis w/in RE system. Patients ill and may only have signs related to anemia, spleno/hepatomegaly, icterus. Ddx: IMHA, SLE, Zn tox (pennies<1982), Heinz body anemia (onions, tylenol in cats), Babesia, Hemobartonella, copper tox, Lepto, endotoxemia.
• Blood loss – Acute blood loss see severe signs bc no time to compensate. Chronic internal blood loss will have no Fe deficiency. Chronic external blood loss via skin, UT, GIT will have Fe deficiency. Ddx: coagulopathy, trauma, ruptured hemangiosarcoma, GI ulceration, nasal epistaxis.
• Nonregenerative Anemia – Microcytic, hypochromic. 1) BM aplastic diseases such as myelofibrosis, neoplasia, Ehrlichia, FeLV. Toxins such as anticonvulsants, chloramphenicol, TMPS, estrogen, phenylbutazone, chemo. 2) 2 failure of erythropoeisis – ACD. Mild to mod anemia. 3) Hemoglobin synthesis defects such as Fe deficiency. 4) 1 failure of erythropoeisis. Pure red cell aplasia, immune mediated disease, estrogen therapy (often given for urinary incontinence). See severe anemia, serum Fe, EP, normal platelets and WBCs. Tx w/ immunosuppressives.
• Circulating nRBCs – Metarubricytes. Ddx: regenerative response (only if orderly), BM dysfunction, splenic dysfunction, extramedullary hematopoiesis, lead toxicity, hemangiosarcoma, heatstroke/vasculitis.
• Anticholinergics – Parasympatholytics. Protect HRs, decrease secretions, decrease threshold for arrythmias. Do not work in rabbits and goats as they have atropinase (why they can eat nightshade).
o Atropine – Muscarinic antagonist. Competitively inhibits acetycholine at postganglionic parasympathetic sites. Low dose inhibits salivation, bronchial secretions, sweating. Moderate dose dilates and inhibits accommodation of the pupil, heart rate. High dose GI and urinary tract motility. Very high dose inhibits gastric secretions. Crosses BBB. May cause ileus in horses. Also, antiemetic, mjydriatic, organophosphate tox tx. Red as a beet, dry as a bone, mad as a wet hen. Tachycardia, dilated pupils.
o Glycopyrrolate vs. atropine – Atropine for emergency, works quicker (but doesn’t last as long only 2-3 hrs). Glyco is 2-4x more potent than atropine, duration of action 4X longer (4-6 hours), prevents bradycardia without causing tachycardia. Glyco does not penetrate BBB (poor lipid solubility), atropine does.
o Tranquilizers - Calm the animal, facilitate handling for induction, amount of induction drugs.
o Phenothiazine tranquilizers (Acepromazine) - antagonist. Neuroleptic. No analgesia. Sedative, antiarrhythmic, antiemetic. Vasodilation, hypotension, lowers seizure threshold, inhibits platelet aggregation, penile paralysis in stallions, HR. Do not use in shocky animals. No reversal. Don’t use in really young, really old, or sick. Avoid in DP dogs.
o Diazepam – Benzodiazepine sedative. Does not work as tranquilizer when used alone. amount of other induction drugs necessary. Anxiolytic, anticonvulsant. Centrally acting muscle relaxant (as is Guaifenesin). Appetite stimulant in cats. In healthy cat as premed, may cause excitement or aggression dt suppression of learned behavior. Flumazenil is reversal agent. Do not give IM, carrier is propylene glycol. Can give midozolam IM (H2O carrier).
o Opiods – Controlled substances. Analgesia, euphoria, antitussive, anti-diarrheal. Hypotension, bradycardia, respiratory depression. Potency of morphine < oxy (10x) < fentanyl (100x). Vagally mediated bradyarrythmias (tx w/ atropine). Naloxone is antagonist. Morphine – pure mu agonist; make vomit; cheap; good for mod to severe visceral pain; epidural gives LT analgesia (up to 24 hrs); give preservative free morphine (normal carrier is formaldehyde). Butorphanol – kappa agonist, mu antagonist; 2-4 hrs duration; very safe; ceiling effect on ventilatory depression, oral form avail. Can effects of morphine, fentanyl (b/c mu antag); not as much sedation or dysphoria. Buprenorphine – partial mu agonist; behaves like kappa agonist; good for mild to mod pain; lasts 6-8 hrs; ceiling effect on ventilatory depression. Naloxone does not reverse resp depression of buprenorphine. Partial agonist means lots of affinity for receptor but not very active once there. Innovar-Vet = Fentanyl + Droperidol.
o 2 agonists - Sedative, analgesic, muscle relaxant. Vagally mediated bradycardia, systemic hypertension, respiratory depression. Sensitizes heart to epi induces arrythmias, arrhythmogenic (1 and 2 heart block),. Can still get kicked/bitten, animals can override. urine production, vomiting in dogs. Xylazine - cattle extremely sensitive (1/10th dose), also sheep and goats; reverse w/ yohimbine. Paralyzes esophageal musculature allowing it to fill w/ air, can look like megaesophagus on rads. 1 side effect in cats is vomiting or retching. Detomidine – reverse w/ telazolin. Medetomidine – reverse w/ atepamazole.
• Barbiturates – CNS depression by inhibiting synaptic transmission and diminishing neuronal excitation in the cerebral cortex and RAS. CBF = cerebral O2 demand = ICP. Splenic vasodilation. Poor analgesia. Rapid smooth induction, arrhythmogenic - sensitizes CV to epi induced arrythmias. sensitivity of laryngeal and bronchial reflexes to ectopic stimulation (laryngeal spasm). CV and respiratory depression. Ultra-short acting - thiopental, thiamylal, methohexital (shortest, best to use in greyhounds). Short acting – Pentobarbital. Pentothal – gold standard; scheduled. BP, HR (baroreceptor mediated). Does not potentiate seizures, good for brain patients, not so good for heart (arrhthmias, bigeminy). Redistributes to fat which affects how wake up (once full, have to metabolize). Avoid in sighthounds, longer sleep time. Causes skin sloughing if outside vein (tx w/ lidocaine, fluids, prayers).
• Propofol – Rapid onset, short duration of action, rapid recovery. Noncumulative. Nonscheduled. CBF = ICP. CV depression, apneic effects (give slowly), response to CO2 depressed. Causes a dose-dependent in arterial blood pressure. Can potentiate arrhythmias. Soybean/egg lecithin based (bacterial medium, care w/ prep and storage), non-irritating. Good for c-sxns and outpatient sx. Do not use in horses, wake up too fast, excitatory. If given daily in cats, can see heinz body anemia.
• Ketamine – Dissociatives are controlled substances. Phencycladine derivative, GABA agonist, glutamate receptor antagonist. Wide therapeutic index. Depresses corticothalamic system, stimulates limbic system. Produces unconsciousness but retain high muscle tone and may move spontaneously, open eyelids, brisk palpebral reflex. Good somatic analgesia, poor visceral analgesia. Bad for cat spays, good for skin grafts, burn patients. Supports CV system by increasing CO, cardiostimulatory – not good if in heart failure. Antiarrhythmic. Seizurogenic. CBF, O2 consumption, ICP. IOP. Hepatic metabolism in most spp, renal in cats. Do not give alone to horses. Add valium w/ cats. Telazol is similar.
• Etomidate - Noncumulative. Very little CV effects and respiratory depression. Good for debilitated patients. Rapid, smooth induction. CBF = ICP without effecting O2 delivery to brain. Give drug slowly to prevent apnea. Suppresses adrenals and cortisol, may need to give a steroid. Expensive. Causes hemolysis of cells in cats.
Potent CV and respiratory depressants. The greater the blood solubility coefficient, the longer it takes for anesthesia to occur. Do not mask induce brachycephalic, vomiting patients. Environmental contamination high when mask induce. Semiclosed O2 flow rate = 15 ml/lb/min. Bain O2 flow = 300 ml/lb/min. rates in bain to remove CO2. Dead space is where 2 way flow – Y piece in circle system.
• Halothane - Most arrhythmogenic. Lowers threshold to catecholamine-induced arrhythmias, then meth, then iso and sevo. Associated with postop liver dysfunction. Cheapest. 25% metabolized. #1 metabolite is bromine, causes lethargy and ataxia. MAC ~ 0.8.
• Isoflurane - Better analgesic than halothane but more respiration depression seen in dogs, cats. Has greatest hypotensive effect. Little or no hepatic metabolism. Minimally metabolized. MAC ~ 1.3.
• Methoxyflurane - Greatest degree of metabolism (50%). B/G = solubility = slow induction. Nephrotoxic. MAC ~ 0.23, most potent.
• Sevoflurane – Interacts w/ soda lime to form nephrotoxic compound A. MAC ~ 2.3.
• Desflurane – Combines w/ Barlyme to form carbon monoxide.
• Nitrous Oxide – Largest MAC value.
Local Anesthetics – Prevent cell membrane permeability to Na+, Ca++ , local anesth. SC never sees the noxius stimuli to begin with. Can mix with epinephrine to duration of effects, but impair perfusion to affected tissue (may slow healing). Procaine (safe, epidural), Lidocaine (IV antiarrhyth, nn blocks), Proparacaine (ophthal), Bupivacaine (thor sx, potent pain, longer duration, slower onset). Morphine epidural can last up to 24 hrs. Brachial plexus block for amputation, intercostal and interpleural blocks, ring blocks for declaws, line block for c-sxn, splash for ear ablation.
Neuromuscular Blockers – For ophthalmic sx, exotics restraint, fundoscopy in birds/reptiles.
• Atracurium – Nondepolarizing; prevents Ach from binding, competitive antagonist. Edrophonium antagonizes (also dx myesthenia gravis).
• Succinylcholine – Depolarizing; bind to Ach receptors and elicit effects causing prolonged contraction; not broken down by Achesterase, long effects. Not in birds.
• Dantrolene – Peripherally acting sk mm relaxant, interferes w/ release of Ca++ from sarcoplasmic reticulum. Used for exertional myopathy, UMN bladder, and malignant hyperthermia tx.
• Inotropes/Chronotropes – Need blood volume and Ca++ for these to work. Chronotropy – iso>dopa>dobuta. Youngsters depend on rate for CO not inotropy.
• Dobutamine - 1 adrenergic agonist. Inotropic. Poor chronotrope, not arrythmogenic. Used in horses. Can use for intraop bradycardia.
• Dopamine - 1, 1, 2 adrenergic agonist. Emergency hypotensive treatment post-resusc. At low dose (2g/kg), vasodilation of renal afferent tubules, if hypotensive and oliguric, urinary output. At medium dose (5g/kg), 1 inotrope, improves cardiac output. At high dose (20g/kg), see affects – vasoconstriction. Use only if post arrest to b ring peripheral pooling back to central compartment.
• Isoproterenol - 1, 2 adrenergic agonist. Extremely chronotropic and arrythmogenic, used for bradyarrythmias, pacemakers and horses that are very fit. Vasodilation.
Depth of anesthesia
• Stage I: All levels of consciousness when patient responsive, including sleep.
• Stage II: Loss of consciousness. Uncontrolled spontaneous reflex activity.
• Stage III: Cessation of spontaneous motor activity. Stage of surgical anesthesia.
Blood pressure - Systolic below 80 and mean below 60 are worry numbers when anesthetized. Hypotension is mean BP<60 for >20min. Assist by anesthetic %, fluid rate, ventilation. Kidney cannot autoregulate when BP<60mmHg.
• Arterial Pressures = CO x Peripheral resistance. CO = HR x SV.
• Systolic 100-160, Diastolic 60-100, Mean 80-120. CVP 0-10.
Blood gasses – Hypoventilation kills slowly, hypoxemia kills quickly.
• PaCO2 - Measures ventilatory status of the patient. Normal 35 – 45 mmHg. PaCO2 < 35 = hyperventilation, HR, CO, BP, injected mucous membranes. PaCO2 > 45 = hypoventilation. PaCO2 > 60 = severe respiratory acidosis. Hypercapnia may be caused by hypoventilation, upper or lower airway obstruction, pleural filling disorders, pulmonary parenchymal disease, abdominal or thoracic restrictive disorders.
• PaO2 - Measures oxygenating efficiency of the lungs. Normal 90 -100. Patients on 100% O2 have PaO2 400-500. PaO2 = 5x what breathing. PaO2 < 60mmHg = hypoxemia.
• SpO2 – predictor of O2 saturation (PaO2). % saturation of Hgb. Measure w/ pulse oximeter, want >90%.
Urine output - Indirect measure of major visceral organ perfusion. Intraoperative urine output should be 1-2 ml/kg/hr, 0.5mg/kg/hr in horse. Renal fxn after general anest and sx in normal, healthy animal for 24-48 hrs.
pH – Acid base status. Normal – 7.4. Primary derangement is always in direction of pH, body won’t overcompensate. 0.3 x bas deficity x wt(kg) = HCO3 mEq (give ½ and reasses).
Temperature – Can spontaneously fibrillate if < 92 F.
Tricaine methanesulfonate (MS-222) – Only anesthetic agent approved by FDA for fish.
E cylinder of O2 – Contains 700L @ 2200 psi
H cylinder of O2 – Contains 7,000L @ 2200 psi
Anestrus (cattle) - result from poor management/nutrition, disease, injury, disturbances in endocrine function. mgmt: failure to detect estrus, avg duration estrus 18 hr. aids in estrus detection: bulls altered, cows/steers given androgen, vaginal probes to measure elect conductivity vaginal mucosa. Non-functioning ovaries: small, smooth bean shaped struct: caused by low energy intake during late winter, droughts on summer pastures, chronic disease, injury, ovarian tumors-anestrous. congential defects: freemartinism, ovarian hypoplasia-anestrous
-inactive ovaries: tx underlying cause tx: detect signs of estrus; absent or regressing CL 3-4 days before onset estrus, small palpable struct,firm uterine tone, palpable follicle. synchr estrus:admin prostaglandin/analog; only effect if funct CL
Angiotensin – Vasoconstrictive principle formed in the blood when renin is released from the juxtaglomerular apparatus in the kidney. The enzymatic action of renin cleaves angiotensinogen to angiotensin I. Angiotensin I is activated in the lung to become angiotensin II (by ACE). Angiotensin II stimulates aldosterone secretion and raises blood pressure, thereby decreasing fluid loss.
Antacids and Antisecretory Agents – Gastric ulceration, hypersecretory diz, EPI, NSAID tox.
• AlOH – Cations bind bile acid, stimulate prostaglandin sythesis, cytoprotective. Rapid. Also binds P in renal disease.
• H2 antagonists – Antisecretory; competitive blockade. Cimetidine – TID, least potent, most bioavailable. Ranitidine – 5-12x more potent, BID, less bioavail, minimal drug interactions.
• Omeprazole - Proton pump inhibitors. Most effective antisecretory.
• Misosprostol – Synthetic prostaglandin, antisecretory. Local effects.
• Sucralfate – Cytoprotective; needs acidic environment to work. Protects and promotes healing; physiologic bandaid. NSAID prophy.
Anterior Uveitis - Inflammation of the anterior uveal tract (iris, ciliary body, choroid).
• Signs - Pain, blepharospasm, tearing, conjunctivitis, constricted pupil, reduced IOP, aqueous flare, keratic precipitates, hypopyon, miosis. Glaucoma, cataract and corneal opacification may be complication.
• Cause - Trauma, infectious systemic disease, intraocular neoplasm, intraocular helminths, immune-mediated disease. Recurrent uveitis immune-mediated.
• Treatment - Topical atropine, corticosteroids if no ulcer, prostaglandin inhibitors, antibiotics.
• Definitions - Blepharospasm - spasm of the orbicular muscle of the eyelid. Aqueous flare - turbidity of the aqueous humor caused by increased protein levels. Keratic precipitates - fibrous deposits on the posterior surface of the cornea, usually associated with uveitis. Hypopyon - pus in the anterior chamber of the eye.
• Pyrantel pamoate. Nemex, Strongid-T. Neuromuscular blocker, paralyzes. Used for roundworms and hookworms in dogs and cats, also Physaloptera. Strongyles, ascarids in horses. Not absorbed, safe for puppies, kittens, pregnant and lactating animals. Pamoate salt limits absorption – just passes through.
• Fenbendazole – Panacur. Least hepatotoxic benzimidozole. Treats rounds, hooks, whips, Taenia, lungworms (cats) and Giardia. NOT effective against D. caninum tapes. 3 doses over 3 days. Febantel is prodrug metabolized to fenbendazole in dogs, don’t use in cats. HPS reactions to dying parasites esp. at high doses. Benzimidozoles interfere w/ parasite metabolism via inhibition of glucose transport = starvation. All are hepatically metabolized. Albendazole is hepatoxic to SA, used in LA. Oxibendazole and Thiabendozole are indicated for removal of equine parasites in addition to use in other animals. (Many equine parasites have developed resistance to their drugs).
• Praziquantel – Droncit, Drontal Plus (combo w/ pyrantel and febantel). Isoquinolone derivative. Widely distributed to tissues after oral admin. Used in tapeworm (cestode) infections, Dipylidium, Taenia, P. Kellicotti, Echinococcus granulosis. Impairs function of sucker, stimulates motility. Puppies >4 wks, kittens >6 wks. May see anorexia, V, D, ataxia. Avoid injectable Droncit – burns.
• Epsiprantel – Cestex. Isoquinolone derivative. Membrane destabilization causing disruption in worm’s integument, host immune system destroys. Tx tapes in cat, dog. >7 wks of age. Not systemically absorbed, safe. Single dose adequate.
• Ivermectin – Macrolide. Enhances the release of GABA. GABA acts as an inhibitory neurotransmitter in nematodes and arthropods. Ivermectin causes paralysis and eventual death of the parasite via increase in Cl- channel permeability. Ivermectin is ineffective against flukes and tapeworms because they do not use GABA as a peripheral nerve transmitter. Mammals do not use GABA as a peripheral nerve transmitter. Heartworm prophylaxis, microfilaricidal; effective against hooks, whips and rounds at higher dose. Lower bioavailability in cats. Young >6 wks old; safe in pregnant/lactating. Does not cross the blood brain barrier. Contraindications: do not use dose higher than prophy dose in collie breeds (does cross BBB). Also contraindicated in shelties, australian shepherds, old english sheepdogs.
• Other Macrolides – Moxidectin, Proheart, heartworm prophy, ok in collies. Selamectin, Revolution, HW prophy, hooks, rounds, fleas, sarcoptes, otodectes. Milbemycin oxime, Interceptor, Sentinel (w/luferenon), HW prophy – make sure HW(-) 1st, microfilaricidal, can cause anaphylaxis; also hooks, rounds, whips, puppies >8 wks.
• Piperazine - Pipa tabs. Only effective against ascarids (roundworms). Paralyzes the worm, allowing it to be passed out with the feces. Blocks acetylcholine at the neuromuscular junction. >3 wks of age. OTC products.
• Levamisole. Imidothiazole. Promotes unchecked excitatory neurotransmitter activity = paralysis, death. Indicated for treatment of many nematodes usually with LA. More effective against adult worms than larval forms. Not effective against horse parasites.
• Arsenicals – Interfere w/ parasite metabolism (inhibit glycolysis), kill adult heartworms. Melarsomine, Immiticide; give IM only. HW infection in dogs. More effective and less irritating, less hepatotoxicity than Thiacetarsemide sodium, Caparsolate. Injection site reactions common, low therapeutic index and low margin of safety in both. Caparsolate can cause significant hepatic and renal damage.
• Diethylcarbamazine – Filaribits. Not used much anymore. Apparent filaricidal activity via paralysis. HW prevention with daily oral dosing, can’t skip a dose. Do not give if MF+, else shock like syndrome. Effective against rounds at higher doses.
Anthrax – Bacillus anthracis. Gram+, nonmotile, spore forming bacterium. Acute, febrile disease of all warm-blooded animals. REPORTABLE. ZOONOTIC. Found in soil. Not communicable between animals, acquire from consumption of contaminated meat, grazing contaminated soil, spore inhalation, or open skin wound.
• Clinical findings – Septicemia w/ rapidly fatal course. Abrupt rise in temp, stupor, staggering, dyspnea, trembling, collapse, sudden death. Bloody discharges from natural body openings. Anorexia, GI stasis, colic, hematuria. Chronic infections characterized by local, SQ, edematous swellings usually in ventral neck, thorax, shoulders. After death, rigor mortis usually incomplete or absent, dark blood from orifices, bloat, rapid decomposition.
• Diagnosis- ELISA, western blot, culture, PCR, IFA. Ddx – other causes of sudden death.
• Treatment and Control – Penicillin, oxytetracycline. Control w/ live vaccine.
• If suspect – Inform regulatory agency, rigid quarantine, prompt disposal of dead, manure, bedding by cremation or deep burial, isolate sick, disinfection, insect repellants, control scavengers, sanitary procedures.
• Penicillins – -Lactams. G+, easy G-, anaerobes. Bactericidal. Inhibit cell wall synthesis. Safe. Elimated via kidney, good for UTIs. Natural penicillins – G+, poor G-, spirochetes, destroyed by penicillinase. PenG and PenV. Penicillinase-resistant penicillins – Penicillinase producing G+ cocci, esp. Staphylococcus. Cloxacillin, dicloxacillin. Aminopenicillins – Broad spectrum, G- activity. Ampicillin, amoxicillin. Extended spectrum penicillins – addl G- activity, Pseudomonas. Carbenicillin, ticarcillin, piperacillin. Potentiated penicillins - Developed to inactivate -lactamases. Clavomox, timentin. Don’t use penicillins in rodents and lagomorphs; elimination of G+ gut flora can lead to fatal colibacillosis.
• Cephalosporins – -Lactams. G+, some G- (more with each generation), anaerobes. Bactericidal. -lactam antibiotics. Inhibit cell wall synthesis. More effective against actively growing bacteria. Classifications – 1st generation cepholosporins include cephalothin, cefazolin, cephapirin, cephadine, cephalexin, cefadroxil. Activity against most G+, poor G- activity. 2nd generation cepholosporins - not very popular, same G+ activity, expanded G-. 3rd generation cepholosporins – same G+ activity, much expanded G- activity; cefotaxime, moxolactom, cefoperazone, ceftiofur (BRD, no withdrawal time).
• Aminoglycosides – 1 G- aerobes. Some G+. Pseudomonas, staphylococcus, atypical mycobacterium (nocardia/actinomyces). Irreversibly bind to 30S ribosomal unit and inhibits protein synthesis. Bactericidal. Includes amikacin (SID, parvo pups), gentamicin, neomycin, and spectinomycin. Inactive against fungi, viruses and most anaerobic bacteria. Accumulate in inner ear and kidneys. Elimination via glomerular filtration. Adverse Effects – Nephrotoxic. Casts in urine, increased BUN and Cr. Nephrotoxicity reversible when drug discontinued. Ototoxic. 8th cranial nerve toxicity. Auditory and vestibular symptoms may be irreversible.
• Fluoroquinolones – Good G- aerobes, facultative anaerobes, atypical mycobacterium, chlamydia, mycoplasma, ehrilichia, BRD. Bactericidal. DNA gyrase inhibitor, prevent DNA synthesis. Enrofloxacin (SID, prostate, RMSF, deethylated to cipro), ciprofloxacin. Variable activity against Streptococci – not recommended. Contraindicated in young animals due to cartilage defects. Baytril associated with blindness in cats.
• Sulfonamides - G+, easy G-, anaerobes; nocardia and actinomyces. Bacteriostatic. Inhibit folic acid pathway (PABA/pteridine not converted to DHFA). Broad spectrum. Many bacteria have developed resistance. Potentiated sulfonamides – TMPS. Bactericidal, inhibits bacterial thymidine synthesis in folic acid pathway. Excellent tissue distribution. Most drug side effects of all Abs, allergic reactions, hepatotoxic, KCS, hypothroidism, crystalluria, thyrotoxic, anemia, BM toxicity (aplastic anemia, thrombocytopenia hypoprothrombinemia).
• Tetracyclines - G+, easy G-, Mycoplasma, spirochetes, chlamydia, Rickettsia, Hemobartonella, Brucellosis. Bacteriostatic. Inhibits protein synthesis by binding to the 30S ribosomal unit. Safe. Prostate. Includes doxycycline (biliary excretion), oxytetracycline, tetracycline. Resistance . May cause esophagitis. Chloramphenicol – G+, G-. Bacteriostatic. Binds to the 50S ribosomal subunit preventing protein synthesis. Penetrates everything. Can cause aplastic anemia in humans.
• Lincosomides – G+ aerobes, anaerobes. No G-. Often combo w/ aminoglycosides. Lincomycin, clindamycin. Bacteriostatic or bactericidal. Bind to the 50S ribosomal subunit. Distribute well, biliary elimination. Contraindicated in rabbits, rodents, horses, ruminants due to serious GI effects.
• Macrolides – G+, selected G-. Bacteriostatic. Bind 50S ribosomal subunit. [ ] in alveolar macrophages, great for pulmonary infections. Erythromycin, tylosin, tilmicosin. Erythromycin is used in the treatment of Rhodococcus equi in combo w/ rifampin. Can cause increase in GI motility. Tilmicosin – used in BRD; CV toxicity in primates, horses, swine.
• Metronidazole - Bactericidal and antiprotozoal. Obligate anaerobes. Disrupts DNA and nucleic acid synthesis. Immunolmodulator in IBD.
• Rifampin - Bactericidal or bacteriostatic. Inhibits DNA-dependent RNA polymerase. Used for treatment of Rhodococcus equi in combo w/ erythromycin.
• Apomorphine – Most consistently effective antiemetic in dogs.
• Atropine – Anticholinergic. Central. Too many side effects for antiemetic use.
• Chlorpromazine – Phenothiazine. Central, antidopaminergic. Very effective centrally acting antiemetic, esp for blood born stimuli. 2nd drug of choice.
• Diphenhydramine – Antihistaminergic. Central. Good for motion sickness, otitis media/interna
• Metaclopramide – Antidopaminergic. Peripheral and central. Physiologically antagonizes vomiting reflex. Also prokinetic from esophageal sphincter to upper duodenum, don’t give w/ obstruction, perforation, or epilepsy. 1st drug of choice.
• Bismuth Subsalicylate – Antiprostaglandin, antibacterial. Peripheral. Antidiarrheal. Care in cats.
• Amphotericin B – Polyene macrolide. Binds to fungal sterols, altering permeability of membrane. Fungistatic. Dimorphic fungi (histo, blasto, crypto, coccidio). Because of the risk of severe toxicity reserved for disseminated, progressive, potentially fatal fungal infections. Nephrotoxic, anaphylactoid.
• Imidazoles – Fungistatic. Inhibit ergosterol/steroid synthesis (blocks cytochrome p450), cell membrane permeability, cell membrane fluidity. Use for dermatophytes, yeast, dimorphic fungi. Impairs steroid sythesis, so sometimes used in hyperadrenocorticism and prostate diz. Ketaconazole – Fairly safe (hepatotoxicity), give w/ food. Short t½. Not got w/ dimorphic fungi, esp. blasto. Itraconazole – more effective spectrum. Fluconazole – Crosses BBB.
• 5-Flucytosine – Ancoban. Inhibits DNA synthesis (antimetabolite, competes with uracil, interfering with pyrimidine metabolism and protein synthesis). Limited spectrum - Cryptococcus, Candida. Rapid absorption, excellent distribution. Synergistic effect with amphotericin B. Adverse effects include BM depression (pancytopenia), GI disturbances, rashes, oral ulceration, increased liver enzymes.
• Griseofulvin – Inhibits fungal mitosis by disrupting mitotic spindle, inhibit nucleic acid and fungal wall sythesis. Limited to dermatophytes only. Give w/ fatty food to absorption. [ ] in keratin. Side effects include GI, teratogenic and carcinogenic at doses, bone marrow dyscrasias. Do not give to pregnant animals.
Antiseptic Agents – Agents applied to the body vs. disinfectants which are used on inanimate objects.
• Alcohol – Protein denaturation. 70% is effective against G+ and G- bacteria. Good bactericidal, fungicidal, virucidal. Most rapid acting but least residual action. Fast kill, defatting agent. Evaporates quickly. 2 min for max effect. May be drying or irritating. May cause cytotoxicity. Often used in combo w/ povidone iodine.
• Chlorhexidine – Cytoplasmic membrane disruption. 0.05% soln effective against Gram+ and Gram-. Persists on skin to give cumulative antibacterial effect. Less irritating. Not inactivated by organic matter. 0.05% is 1:40 dilution, most bactericidal and least toxic to tissues.
• Hydrogen peroxide – Poor antiseptic. Short-acting germicidal effect through release of nascent O2, irreversibly alters proteins. Effective sporicide. Effervescent action mechanically removes pus and bacteria.
• Iodine – One of most potent antiseptics. Bactericidal, virucidal, fungicidal. Takes 15 min for sporicidal action.. Organic matter inactivates free I in PI. Iodine Soln USP has little to no stinging on broken skin. Iodine tincture USP (I in alcohol) is even more effective, but stings and irritates skin. Rare HPS rxns. Povidone iodine often used in conjunction w/ alcohol. Use PI in 0.1 to 1% [ ]; more dilure solns have free I and faster, potent bactericidal activity. Dilute stock solution 1:100 or 1:10. Don’t use I scrub on open wounds –damage tissue and infection.
• Iodophors – Betadine. Aqueous complex of iodine, less bactericidal but also less irritating. Gram-, gram+. Do not require repeated application for optimal antimicrobial effect. Contact time 10 min for max effect.
• Hexachlorophene – Gram+ bacteria. Only effective after days of use once film deposition on skin, long contact time. CNS toxin if absorbed, esp in young. Not used much anymore.
• Quaternary ammonium compounds - Changes in cell membrane permeability. G+. Inactivated by organic debris and soaps. Not recommended.
Aortic thromboembolism - usually primary underlying cardiac disease. hypertrophic cardiomyopathy maybe present. left atrial enlargement results from mitral regurgitation or increased end-diastolic pressure thrombus formation; left atrium; thrombus dislodges forms an embolus that obstructs aortic branches. site of embolization: aortic trifurcation. clin signs: sudden onset of posterior paresis, severe pain, and muscle spasm; weak or absent femoral pulses, hindlimbs are cool. aortic trifurcation:not completely occluded, unilateral paresis or only mild neurologic deficits in both hindlimbs. tx: sx: not recommended due to possibility of acute hyperkalemia and metabolic acidosis severe enough to cause cardiac arrest. medical tx: administration of fluids (to maintain hydration and blood pressure but not exacerbate congestive heart failure), analgesics, anticoagulants, and therapy specific for underlying cardiac disease heparin & warfarin: not effective against established thrombus. many cats die or don’t regain hindlimb use. some paralyzed cats: recover function after 3-7 weeks
Arginine – Essential amino acid for cats. Needed to “drive” the urea cylce b/c it transforms ammonia into urea. Arginine deficiency may potentiate hepatic encephalopathy.
Arsenic Poisoning - Sources include rodenticides, wood preservatives, weed killers, baits, insecticides.
• Clinical signs - Acute effects on GIT and CV system. Profuse watery diarrhea, may be blood tinged. Severe colic, dehydration, weakness, depression, weak pulse.
• Diagnosis - Determination of arsenic levels in tissue and ingesta.
• Treatment - Thioctic acid, Dimercaprol (BAL). Phenylarsonic toxicosis - arsenical additives to swine and poultry diets to improve production, treat dysentery. Toxicosis results from excess supplementation. Signs in pigs include reduction in weight gain, incoordination, posterior paralysis, blindness. Neurotoxic effects reversible once feed removed. Paralysis and blindness irreversible.
Arthridites in Lambs - Causes of lameness in lambs include joint-ill, tetanus, white muscle disease, enzootic ataxia (copper deficiency), polyarthritis (chlamydial), rickets, poisonous plant intoxication (sneezeweed), and contagious ecthyma (orf). In any age, also erysipelas (important), laminitis, bluetonque, ulcerative dermatosis, foot-and-mouth disease, dermatophilosis.
Arytenoid Chondropathy or Chondritis – Horse. Bilateral inflammation of the arytenoid cartilage causing exercise intolerance, noise, coughing, dyspnea, syndrome similar to that caused by recurrent laryngeal nerve paralysis. Dx via endoscopy. Tx – partial/total arytenoidectomy (leave muscular process). Bilateral – temporary and permanent tracheotomy.
Ascariasis - Toxocara canis, felis. Roundworms found in the SI of dogs and cats. See Roundworms..
Asthma - most common in cats. occurs most commonly in summer. clin signs: wheezing, coughing;severe attacks: expiratory dyspnea, hyperinflation of the lungs, aerophagia, cyanosis
Aspergillosis – Inhaled fungus. Most common nasal fungal infection in dogs (A. fumigatus), esp dolichocephalics. Urinary aspergillosis in GSD, systemic. 1 a respiratory disease. Causes pulmonary infections in birds and death in penguins, mycotic abortion in cattle, gutteral pouch mycosis in horses, infections of the nasal and paranasal tissues of dogs. Clinical signs and lesions in birds include yellow nodules in respiratory passages, etc. See matts of hyphae. Eats away at turbinates. Tx w/ itraconazole and others. Flush nasal cavity w/ chlortrimazole.
Aspiration pneumonia – Right middle lung lobe most commonly affected (1st major bronchus). 2 complication in many diseases. Can be fatal. Treat aggressively with antibiotics.
Aspirin – NSAID. Irreversibly inhibits cyclooxygenase (prostaglandin synthetase) thereby synthesis of prostaglandins and thromboxanes. Platelets cannot synthesize new cyclooxygenase causing an irreversible effect reduction of platelet aggregation. Antiinflammatory by local actions, antipyretic and analgesic by effects on CNS.
• Pharmacokinetics - Metabolized in the liver by conjugation with glycine and glucuronic acid via glucuronyl transferase. Cats are deficient in this enzyme, so aspirin has a prolonged half life in cats and may accumulate. Excreted by kidneys.
• Use - Analgesia, antipyretic, antiinflammatory, inhibition of platelet aggregation.
• Adverse eff ects - GI ulcers. Toxicity in cats.
• Comparison of NSAIDs - Phenylbutazone more effective peripherally (antiinflammatory) than centrally (antipyretic). Acetaminophen has weak peripheral actions and does not produce significant GI irritation, nor does it have siqnificant antiinflammatory activity, though it acts centrally as an analgesic.
Atopy - Type I HPS, histamine mediated release from mast cells. IgG mediated. Hives, wheals, urticaria distributed to face, feet, ears, armpits, legs in dogs. Miliary dermatitis in cats. Includes food allergies and atopic dermatitis dt inhaled allergens. Intradermal skin testing and ELISA testing (controversial)). Remove offending allergen, hyposensitization, glucocorticoids.
Allergic inhalant dermatitis - type I hypersensitivity. genetically predisposed. allergens inhaled, absorbed through skin—IgE production; allergen IgE fixed to tissue mast cells, contact specific allergen—inflammatory response. breed predilection: Shar Peis, Wirehaired Fox Terriers, Golden Retrievers, West Highland White Terriers, Scottish Terriers, Shih Tzus, Dalmatians, Lhasa Apsos, Boxers, Boston Terriers, and Labrador Retrievers
-age: btwn 6 mos- 7yrs, usually by 3 yrs. usually seasonal, 75% animals pruritic year round
-pruritic:feet, face, ears, abdomen, axillae. DDX: food allergy, flea allergy, contact allergy, scabies, pyoderma, and Malassezia dermatitis. TX: 3 options - avoid allergen, symptomatic tx, immunotherapy (hyposensitization) -hyposensitization:aim to incr animal’s ability to tolerate exposures to allergens. Clin signs problematic several times/yr, cooperative for shots: suitable candidate. id offending allergens. induction period: conc grad incr & reach maximum; maintenance level continued. symptomatic tx: glucocorticosteroids, antihistamines, and topical treatments, antibiotics. DDX: superficial bacterial folliculitis (usually due to Staphylococcus intermedius ), seborrheic skin disease, and Malassezia dermatitis
Atopy - diff from canine. pruritic dz with hypers to inhaled allergens. clin signs: milliary dermatitis, symmetrical alopecia, head & neck pruritis, eosinophilic granuloma complex.
-age: before 5yr. breeds: Siamese, Burmese, tx:steroids -dx:intradermal testing, hyposensitization
Atrophic rhinitis - Bordetella bronchiseptica, Pasteurella multocida. Pigs.
• Clinical signs - Sneezing, followed by atrophy of turbinate bones. Signs begin in pigs 3-8 wks.
• Diagnosis - Signs, lesions, culture
• Control - Difficult to keep herds free of diz, but usually low level. Control measures taken when reach unacceptable levels. Antibiotic (tet, sulf, tm, tyl) administration to prefarrowing sows, newborn piglets, weaners. Bacterin admin to sows (4 and 2 wks prefarrowing) and piglets (1 and 4 wks).
Atropine – Anticholinergic, antimuscarinic. See Anesthesia section. Used as preanesthetic to respiratory secretions, prevent sinus bradycardia and AV block. Also an antidote for cholinergic overdose (physostigmine) and organophosphate toxicity. Don’t use in patients with glaucoma.
Atypical pneumonia - Includes acute bovine pulmonary emphysema and edema (ABPEE), fog fever, bovine atypical interstitial pneumonia. One of the more common causes of acute respiratory distress in cattle, esp adult beef cattle. Typically occurs in autumn, 5-10 days after change to a lush pasture. Lush pasture high in L-tryptophan, which is degraded in the rumen to indoleacetic acid, which is converted by rumenal microorganisms to 3-methylindole. 3-MI is absorbed into the bloodstream and is the source of pneumotoxicity after it is activated by pulmonary macrophages.
Autonomic Nervous System – Involuntary branch of peripheral efferent nervous system; works in conjunction w/ somatic NS which is voluntary branch of efferent division. Innervates cardiac mm, smooth mm, most exocrine glands, some endocrine glands. Neurotransmitters are acetylcholine and norepinephrine. ANS subdivides into sympathetic and parasympathetic NS. Cell body of 1st neuron in CNS – preganglionic fiber – cell body of 2nd neuron in ganglion outside CNS – postganglionic fiber – effector organ. Most visceral organs dually innervated by SNS and PNS
• Sympathetic NS – Fight or flight. Originate in thoracolumbar SC. Short preganglionic fibers, synapse w/ ganglia in sympathetic trunk. Long postganglionic fibers to effector organs.
• Parasympathetic NS – General housekeeping (SLUDDE). Originate in craniosacral SC. Long preganglionic, short postganglionic.
• Acetylcholine – Neurotransmitter for both sympathetic and parasympathetic preganglionic fibers. Also, parasympathetic postganglionic neurotransmitter. Called cholinergic fibers. Ach also acts at sympathetic postganglionic fibers of sweat glands and efferent skeletal muscle terminals.
o Cholinergic receptors:
Nicotinic – Found on postganglionic cell bodies in all autonomic ganglia. Respond to Ach released from both sympathetic and parasypathetic preganglionic fibers. Also on motor end plates of skeletal mm.
Muscarinic – Found on effector cell membranes of smooth mm, cardiac mm and glands. Bind w/ Ach from parasympathetic postganglionic fibers. Atropine blocks muscarinic receptors.
• Norepinephrine – Released by sympathetic postganglionic fibers. Called adrenergic fibers (adrenaline). Also acts at adrenal medulla.
o Adrenergic receptors:
– Norepi. Excitatory response in effector organ. In general, smooth mm constiction.
- Epi. 1, 1 in heart, excitatory response. 2, generally inhibitory, relaxation of smooth mm causing bronchodilation and vasodilation.
1 – Postsynaptic, smooth mm and glands
Agonist: epi norepi >> iso
• constriction and excretion
• Contract radial mm of iris – mydriasis
• Contraction of 3rd eyelid
• Contraction of splenic capsule
• Hyperpolarization and relaxation of intestinal smooth mm 1 – Heart. Cardiostimulant.
Agonist: iso > epi = norepi
• Positive inotrope and chronotrope
• AV nodal conduction velocity
• Inhibits motility and tone of SI
• blood pressure via in renin secretion from juxtoglomerular cells, conserve Na+ and H2O
2 – Presynaptic, feedback inhibitor
Agonist: xylazine, detomidine
Antagonist: yohimbine, atipamezole, tolazoline
• Inhibits gut Ach ( motility)
• Postjunctional 2 acts like 1 to contract smooth mm
• insulin secretion from pancreatic islet cells 2 – Bronchioles. Inhibitory to smooth mm.
Agonist: iso > epi >> norepi
• Relaxation of smooth mm
• Vasodilation to abd viscera, kidneys, lungs, and skeletal mm.
• Glycogenolysis and uptake of K+ in sk mm
• Gluconeogenesis in liver
Avascular Necrosis of Femoral Head – “Leg Perthy’s Disease” in humans. Effects young toy and small breed dogs. Decreased blood supply to femoral head and neck, femoral head collapses, pathologic fracures can occur, osteoarthrosis. Usually unilateral lameness. Can be traumatic or spontaneous. On rads, see opacity of femoral head and neck, collapse of femoral head, joint laxity. Sx, require FHO. Warn O that may occur in other side later.
Avian Anatomy and Diagnostics –
• Feathers don’t grow continuously, molt once a year (some spp twice); new feathers have blood supply.
• Urophygial gland at dorsal base of tail for preening.
• Proximal axial skeletal system is pneumatized. Do not attempt to get BM or put catheters in femur or humerus.
• Eyes have skeletal muscles in the iris, cannot dilate pupil w/ atropine (use NM blocker). Optic chiasm 100%, no concentual PLR.
• Respiratory system requires filling of air sacs with 1st breath, goes to caudal air sac, lungs, cranial air sac and back out.
• Digestive system is beak-tongue-cervical esophagus-crop-thoracic esophagus-proventriculus (glandular stomach)-ventriculus (grinding)-intestines-cloaca.
• Lobulated kidneys are dorsal in synsacral fossa. Renal portal system in addition to hepatic portal system, why don’t give injections in hindlimbs (filtered prior to systemic circulation). Birds can decrease GFR b/c uric acid is secreted not filtered. Assess renal fxn w/ uric acid; severe renal failure leads to gout.
• Liver measured by AST and bile acids (not SAP, ALT), eval CPK concurrently. Icterus is rare, see bright green urates when urates should be white.
• Female has 1 ovary on left, poultry have right remnant (often cystic). Males have 2 testes, some have phallus.
• Heart has 4 chambers, right AV valve is muscular not tendinous. R aortic arch, not L.
• Do not have lymph nodes but lymphoid tissue – if spleen enlgd, serious systemic disease. Lymphoid tissue includes thymus and bursa of fabrecious (outpouching of cloaca), both of which shrink up w/ sexual maturity.
• Heterophils instead of neuts w/ rod shaped granules, nucleated thrombocytes instead of platelets, nRBCs.
Avocado – Pulmonary edema and death in birds.
Avulsion fracture - A fragment of bone, which is the site of insertion of a muscle, tendon or ligament, is detached as a result of a forcef ul pull. Repair with a pin or screw.
Abscesses (rabbits) - caused by Pastereulla . bucks penned; fight;wounds abscess
-septicemia, death within 24 hrs. lesions: bronchial congestion, tracheitis, splenomegaly, sq hemorrhages. tx: pet rabbits: drain abscess, Ab treatment. colony rabbits: cull rather tx
Adrenal tumor (ferrets) - adenoma and/or adenocarcinoma. can result in hyperadrenocorticism, xs secretion sex hormones. age ~1.5 yr. clin sign: hair loss on tail & rump- flank, head. Females: swollen vulva, enlarged mammillae. males: aggressive, stranguria secondary to prostatic enlargement. bone marrow suppression with hyperestrogemia occur. bld work:normal
-def diagnosis: sex hormone panel. histopath: adenoma, adenocarcinoma, hyperplasia
-tx: surgery: can result in hypoadreno;tx with mineralocort, glucocort supplementation
-medical mgmt: Leuprolide acetate: GnRh agonist, dose 100 microg 1x/month or 2mg/kg q 4
mos, lifelong tx, monitor with ultrasound q 6 mos . melatonin 1 mg/ferret to counteract alopecia
Antibiotic toxicity (guinea pigs) - overgrowth of Clostridium dificile, toxins released
-results in enterocolitis, diarrhea, death in 3-7 days. G+ spectrum Abs should not be used: penicillin, lincomycin, erythromycin, tylosin. broad spectrum Abs-affect intestinal flora when used orally. use with caution parentally
Abscesses (iguanas) - result of trauma, bite wounds, poor environmental quality. sq abscesses: nodules, swellings. various aerobes Pseudomonas, Aeromonas, Serratia, Salmonella, Micrococcus, Erysipelothrix, Citrobacter freundii, Morganella morganii, Proteus, Staphylococcus, Streptococcus, E. coli, Klebsiella, Arizona, Dermatophilus
-sm abscesses: removed. lg abscesses: incised, lining scraped, local Abs tx
-tx with metronidazole, ceftazidime (anaerobic bacteria)
Arthritis – septic (horses) - bacterial infection in joint. develops in 3 ways: navel ill (hematogenous infection), traumautic injury, iatrogenic infection associated with joint injection or surgery (usually in horses). clin signs: severe lameness and distention of the joint with cloudy, turbid synovial fluid that contains >30,000 WBC/mm3 and a total protein level of >4 g/dL
-foals:hematogenous osteomyelitis accompanies septic arthritis
-3 types: type S: septic joint only; type P: (involving osteomyelitis of the adjacent growth plate, type E: osteomyelitis of the epiphyseal and subchondral bone.
control: reducing the possibility of infection from the environment. systemic antibiotic treatment is often combined with intra-articular antibiotics. adjunctive treatment with nonsteroidal anti-inflammatory drugs (eg, phenylbutazone)
Arthritis – traumatic (horses) - includes traumatic synovitis and capsulitis, intra-articular chip fractures, ligamentous tears (sprains) involving periarticular and intra-articular ligaments, meniscal tears, and osteoarthritis. acute stage: synovial effusion. chronic stage: general thickening and fibrosis. traumatic synovitis and capsulitis: diagnose by radiographs to rule out osteochondral fractures or disease. tearing of ligaments or menisci: rule out by arthroscopy
-osteoarthritis is diagnosed with radiographs. clin signs: pain, altered function joint
-active process: synovial effusion, and the surrounding tissues are swollen and warm
-severe cases: pain elicited upon manipulation
-flexion test used in more subtle cases, cause lameness
-tx: rest and physical therapy regimens such as cold water treatment, ice, passive flexion, swimming, NSAIDs (phenylbutazone), polysulfated glycosaminoglycans (PSGAG) IM, 500 mg.
Actinobacillus pleuropneumoniae (pigs) – acute. causes severe pleuropneumonia, or subacute or chronic resulting in pleuritis and pulmonary sequestration and abscesses. immune complexes may damage endothelial cells, resulting in vasculitis and thrombosis leading to edema, necrosis, infarction, and hemorrhage. usually pigs <5 mos. tx: penicillins, tetracycline, erythromycin, spectinomycin, or cephalosporins
Actinobacillus suis (pigs) - auses septicemia, usually pigs <3 mos. arthritis, pneumonia, and pericarditis ;older pigs. normal flora of the pig's oral cavity. immunosuppression or a break in the integrity of the oral mucosa results in disease. tx: tetracyclines, potentiated sulfas, or cephalosporins
Aflatoxicosis (mouldy corn) - metabolites M & M. caused by Aspergillus flavus & Aspergillus parasiticus. found on corn, peanuts, silage when moisture content & temp high for mold growth, >70 deg. affects young pigs, adults susc when fed over period of time. dietary levels <200ppb in finishing pigs, <50 ppb weaner pigs. toxins bind to nucleic acid, nucleoproteinmutagenesis decr protein growthliver affected. acute outbreaks; assoc concentrations in feed >1000 ppb
- deaths: after a short period of inappetence; widespread hemorrhages and icterusliver
- marked fatty accumulations and massive centrilobular necrosis and hemorrhage
-chronic: unthriftiness, weakness, anorexia, and sudden deaths
--liver enlarged, firm; edema gallbladder; kidneys: tubular degeneration & regeneration
-control: monitor batches feedstuff for aflatoxin. hydrated sodium calcium aluminosilicates (HSCAS) fed @ 10 lb/ton (5 kg/tonne).
Anemia (pigs) - Nutritional:rare exept for iron deficiency;critical for young pigs; lack of dietary iron. older pigs;assoc with GI lesion-chronic bleeding-deficiency:microcytic (low MCV),
hypochromic (low MCHC). tx:transfusions, iron supplement. make sure not Vit E def
-3 forms: 1st:damage to injection siteK+ releasedbld K+ levels incrheart affected. whole litter affected. swelling @ site. clin signs: piglets anemic, become weak, cannot stand, muscle tremors followed by convulsions. respiratory distress. lesions: muscles pale, edema & blk discoloration @ inj site
-2nd: piglets, assoc with E. coli enteritis, excess iron overwhelms phagocytic cellsinfection. cause of death: enteritis
-3rd: calciphylaxis; rare; massive mobilization of calcium after injection of iron preparations in the presence and absence of supplementary vitamin D. occurs within days of iron supplementation. hard swellings at injection sites. death may occur
Babesiosis – Babesia canis, B. gibsoni in dogs, B. felis in cats, B. bigemina, B. bovis in cows. Intraerythrocytic protozoan parasite transmitted by ticks. Dogs and cats – Rhipicephalus, the brown dog tick and some Dermacentor. Boophilus tick spp in cattle. Destroys RBCs intravascularly during escape from cells. No human health risk.
• Clinical signs – Can look just like IMHA, regenerative anemia. Most subclinical. If immunocompromised or splenectomized (parasitized cells removed by spleen), see Hgburia, hgbemia, anemia, hemolysis, icterus. Death.
• Diagnosis – Hx of tick infestations. Giemsa-stained capillary blood or organ smears. ELISA, IFA. Often Coombs +, polyclonal gammopathy.
• Treament – Imidocarb dipropionate (Imizol), Diminazene aceturate (Berenil). Feline may be nonresponsive, primaquine phosphate reported to be effective.
Bacillary hemoglobinuria - Clostridium hemolyticum. "Red water disease.” Acute, infectious, toxemic disease primarily of cattle. Soil borne organism found naturally in alimentary tract of cattle. Latent spores become lodged in the liver, where they germinate. The resulting vegetative cells produce phospholipase C, which causes acute hemolytic anemia.
• Clinical findings - Acute hemolytic anemia. Sudden onset of severe depression, fever, abdominal pain, dyspnea, dysentery, hemoglobinuria, anemia, jaundice.
• Diagnosis - Port-wine colored urine. Liver infarct. Normal size and consistency of spleen, IFA of liver.
• Control - Early treatment with penicillin – C. hemolyticum bacterin in endemic areas.
Bacterial Pneumonia (equine). Rhodococcus (Corynebacterium) equi - severe pneumonia- may be endemic on some farms. Also maybe secondary to viral dz. Acute bronchointerstitial pneumonia affects foals 1 wk to 8 months old, and the etiology is unknown. R. equi and P. aeruginosa have been identified. Marked by acute or peracute onset, respiratory distress, cyanosis, reluctance to eat, septicemia, DIC, increased fibrinogen concentrations, radiographs showing increased alveolar and neutrophilic leucocytosis.
Dx: Culture of bronchoalveolar lavage or a tracheal wash (nasal swabs not recommended because of resident microflora). The diagnosis of respiratory infections is usually based on a combination of history and results from clinical, endoscopic, radiographic, and in some cases, ultrasonographic examinations.
Tx: Abs (eg, penicillin, potentiated sulfonamide& bronchodilators.
Bacterial sepsis -
Bacterial enteritis (guinea pigs) A number of bacteria are capable of causing infections of the gastrointestinal tract in guinea pigs. Some of these bacteria are introduced through contaminated greens or vegetables or in contaminated water. One of the most common bacteria that cause intestinal disease in guinea pigs is Salmonella spp. Other bacterial species that may cause diarrhea and enteritis are Yersinia pseudotuberculosis, E. coli, Arizona spp., and Clostridium spp. In addition to diarrhea, other common symptoms associated with intestinal disease are lethargy and weight loss. In other cases, however, sudden death may occur before expression of these signs.
Barium Series – Should move out of stomach into duodenum by 30 min. Reach ileocolic valve w/in 2 hrs.
Bartonellosis (cats) - Bartonella Henselea.(intracellular RBC g -ve. bacteria) Cat scratch fever. (cats are asymptomatic carriers). The risk of zoonotic transmission is low (unless immunocompromised). Humans will present an ocular reaction.
Dx: blood culture, antibody titer (indicates exposure)Tx: enrofloxacin, doxycycline (efficacy in uncertain).
Beak deformities (congenital and traumatic) Lateral deviation of the maxilla occurs most frequently in macaws, but is occasionally observed in other species. Mandibular prognathism, also called maxillary brachygnathism, occurs most frequently in cockatoos, but may be seen in other species. Early discovery of beak deformities will facilitate easy correction. Physical therapy and corrective grinding may be corrective in cases that are discovered early, but orthodontic devices or prosthetics may be necessary to correct beaks that have already hardened. Beak overgrowth is seen in parrots with no chew toys. Psittacine Beak and Feather disease- viral, immunosuppressive disease, often die of 2 causes. Feather disease w/ damaged follicles, dystrophic feathers, hemorrhage in shafts. Necrotic beaks. Old world birds at risk PCR of blood sample to dx.
Beef quality assurance / food safety: Pesticides/ herbicides and other chemicals, molds, mycotoxins, feed additives and medications, etc. cause problems. Withdrawal periods should be strictly enforced. All im and sq injection should be given in the neck region. Ruminant derived protein should not be fed. No more than 10cc of im injection per site. No extra-label use of nutritional additives. Records are to be maintained for a minimum of two years.
Behavior problems (dogs and cats): Most behavior modification focuses on counterconditioning and desensitization using food treats or rewards. Antianxiety medications (eg, amitriptyline, clomipramine, fluoxetine) have been helpful in treating the anxiety associated with the aggression and in facilitating the behavior modification. May be: Dominance aggression, Fear aggression, Idiopathic aggression, Inter-animal aggression, Pain aggression, Play aggression, Predatory aggression, Status-related aggression, Redirected aggression and Territorial aggression
Bence-Jones Proteins – In urine, comprised of immunoglobulin light chains.
Bethanocol – Parasympathomimetic used for treating disorders of micturition when no obstruction present. Other drugs include dantrolene, diazepam, diethylstilbestrol, estrogen, testosterone, propantheline. Cholinergic, effects primarily muscarinic, negligible nicotinic activity. Has duration of action compared to acetylcholine. Used to detrusor muscle tone and stimulate bladder contractions in small animals. Also an esophageal or GI stimulant, but metoclopramide and neostigmine are better.
Bicarbonate Deficit Replacement - Base deficit x 0.3 x kg = mEq bicarbonate
• Normals: base deficit 0 4 mEq/L
bicarbonate 24 4mEq/L
CO2 25 4mEq/L
• Base deficit values below -10 and bicarbonate values below 14 warrant therapy.
Biliary Tract Obstruction – Bilirubin causes normal colored feces. If no bilirubin, as in complete obstruction, get pale white feces (i/d, rice will also do this). 1st change is SAP, then hyperbilirubinuria, then hyperbilirubinemia. #1 cause of BTO is pancreatitis. In surgery, if see little white dots, suponified fat, not mets. Biopsy in pancreatitis in cats (uncommon). Bilirubinaemia and bilirubinuria. Dogs (males more than females) have a low resorptive threshold for bilirubin and also have renal enzyme systems that produce and conjugate bilirubin to a limited extent. Therefore, mild bilirubinuria (up to 2+) can occur in normal dog urine of greater than 1.025 specific gravity Cholangitis, cholangiohepatitis :Rare in dogs. The acute suppurative presentation is often associate with bacterial, fungal or protozoal infections, the chronic, nonsuppurative presentation is believed to be due to an underlying immune condition. Often in association with chronic pancreatitis, IBD or fluke infections.
CS:fever, hepaomegaly, abdominal pain, icterus, lethargy, vomiting and anorexia.
Dx: moderate ALT, AST and GGT increase, mild anemia, hyperbilirubinemia
Tx: ampicilin, amoicilin or metronidazol and gentamicin. Sx: cholecystojejunostomy.
Biliary cirrhosis Rare condition, animals normally die before reaching this condition. It is the end stage of cholangitis and aholangiohepatitis.
CS: icterus, hepatomegaly, cacheia and ascites.
Dx: hypoalbumenia, hyperglobulinemia, hyperbilirubinemia and coagulopathies.
Tx: high protein diest, angiotensin-converting enzyme inhibitors (Enalapril) or loop diuretics (furosemide)
Bismuth Subsalicylate – Effective antisecretory dt salicylate. Good for acute diarrhea.
Bite wounds: Cat bite wounds must be treated like an abscess. In dog bite wounds, more damage beneath the surface (ribs, etc.). Tx: wound should be surgically extended. Do not close contaminated wounds. Closure using drains or second intention healing.
Blackleg - Clostridium chaovoei. Also C. septicum and sordelli. An acute febrile disease of cattle and sheep characterized by myonecrosis and emphysematous swelling, usually in the heavy muscles. Caused by ingestion of spores and deposition into mm. Usually in young adult beef cattle w/ no hx of trauma. Usually trauma induced in sheep. Most common in summer and fall.
• Clinical findings - Crepitant swellings of the heavy muscles. Acute lameness. Acute death in healthy young beef cattle.
• Diagnosis - History, clinical findings, IFA.
• Control – Vaccination
Bladder tumors : Primary malignant tumors (usually Transitional Cell Carcinoma) are the most common neoplasm of bladder. Benign tumors are uncommon. Usually, TCCs are solitary or multiple pappillary like projections from the mucosa. Obstructive tumors may lead to secondary hydronephrosis and/or bacterial UTI/ CS: hematuria, dysuria, stranguria and pollakiuria. In cases with hydronephrosis signs of uremia are seen. Urine sediment may contain neoplastic cells. Dx: cystourethrogram or pneumocystogram. Prognosis is not good. Tx: surgical removal or chemotherapy.
Iguanas: uric acid calculi (maybe caused by high protein diet). Blood in droppings. DX -radiography. Tx- surgery and fluid therapy
Blastomycosis - Blastomyces dermatitidis. Fungal disease of the midwest. Hunting dogs. Large (8-20m) broad based budding yeast w/ refractive cell wall. Infection causes primary granulomatous or pyogranulomatous lesions in the lungs. Ns infiltrate. May occur in the skin, eyes, bone and elsewhere. Draining cutaneous tracts, respiratory disease. Bone diz looks like tumor (ddx coccidio). AGID test, serology. Tx w/ amphotericin B (nephrotoxic). Poor px if disseminated.
Blister Beetle – Cantharidin toxicity. Most often in horses. Blister beetles swarm in alfalfa hay during harvesting. Beetles contain cantharidin, a potent irritant and vesicant that causes GI and renal signs as well as hyperemia and ulceration of the oral, esophageal and GI mucosa. Clinical signs include colic, salivation, choke, pollakiuria, hematuria, hypocalcemia, hypomagnesemia. Horses can die within 48 hours. Treat with supportive care.
Bloat. Affects all ruminants. 1 Frothy : from fresh legumes (alfalfa, ladino, and red and white clovers) in pasture or hay; or irregularly fed, and then feed again. 2 Free Gas: from esophageal obstruction or ruminal atony ; because no eructation. CS: In 1 bloat: sudden death may occur. As bloat progresses, the skin over the left flank becomes progressively taut and, cannot be “tented.” Dyspnea and grunting, mouth breathing, protrusion of the tongue, and extension of the head. In 2 bloat, tympanic resonance over the dorsal abdomen left of the midline. Free-gas produces a higher pitched ping on percussion than frothy bloat. Passage of a stomach tube or trocarization releases large quantities of gas and alleviates distentionTx: Emergency rumenotomy in life threatening cases. Otherwise, pass stomach tube. Vegetable oils, mineral oils, dioctyl sodium sulfosuccinate, etc.
Blood - Hemoglobin formation consists of a globin molecule and four heme groups. Each heme group contains an iron atom with which a molecule may associate and dissociate. Each Hbg molecule can transport a max of four molecules of O2. Each erythrocyte contains 200-300 million molecules of hemoglobin. When blood passes through the lungs, Hgb becomes saturated with O2, forming oxyhemoglobin. When this blood passes through body tissues, some of the O2 dissociates from the Hgb. Normal blood contains 15 grams Hgb per decaliter. 98% of that is saturated with oxygen.
Blood and Plasma therapy – Transfusion - wt (lbs) x 40(dog) or 30 (cat) x desired PCV – patient PCV/PCV of donor. Rate approx 10ml/kg/hr, slowly at first to check for adverse rxns. If giving to fast, patient will vomit.
In foals - neonatal isoerythrolysis – need whole blood transfusion – also in cases of acute blood loss.If the oxygen –carrying capacity of bld is to be increased, use RBC.If circulatory volume increase is needed, provide crystalloid or colloid solutions. If coagulation factors are needed, use fresh-frozen plasma or cryoprecipitate if the need is specifically for factor VIII, von Willebrands factor, or fibrinogen. Platelet-rich plasma or platelet concentrates may be of value in thrombocytopenia, although immune-mediated thrombocytopenia usually does not respond to administration of platelets because they are removed rapidly by the spleen. The anticoagulant of choice is citrate phosphate dextrose adenine (CPDA-1). If the blood will not be used immediately, the plasma can be removed and stored frozen for later use as a source of coagulation factors or albumin for acute reversible hypoalbuminemia. Chronic hypoproteinemia is not helped by plasma because the total body deficit of albumin is so large that it could not be improved by the small amount contained in plasma. Transfusions can also spread disease from donor to recipient, such as RBC parasites (eg, Haemobartonella , Anaplasma , or Babesia ) and viruses (eg, equine infectious anemia, or other slow viruses). Other diseases, such as those caused by rickettsia or other bacteria, can also be spread if the donor is bacteremic.
Blood Types –
• Cat – A, B, and AB. Severe transfusion rxns in type B cats receiving type A blood. Type Bs carry alloantibodies to type A. Purebreds are more commonly type B. Risk for severe rxn on 1st transfusion. AB is very rare.
• Dog – A (DEA1.1 or DEA1.2), B,C,D, F, Tr (DEA7), J,L,M,N. Natural antibodies are anti-B,-D,-Tr. Donors should be DEA1.1, DEA1.2 and DEA7 negative. Neonatal isoerythrolysis assoc w/ anti-DEA1.1.
• Horse – A,C,D,K,P,Q,T,U. Natural antibodies anti-A,-C. NI assoc w/ Aa or Qa. Donors should be non Aa or Qa.
• Cow – A,B,C,F,J,L,M,R,S,T,Z. Natural antibodies anti-J. B system most complex w/ >1000 alleles.
• Blood Donor – Ideally same blood type or at least w/out reactive antigens
• Cross Match - Major: 2 drops donor RBC in 2 drops recipient serum; if incompatible, recipient serum contains Abs to donor RBCs. Most important, if incompatible, cannot tranfuse for any reason. Minor: 2 drops recipient RBC in 2 drops donor serum; if incompatible, donor serum contains Ab to recipient RBCs. Cannot transfuse plasma, but can RBCs, if washed and major cross match compatible.
Blood Volume - Total body water = 60% of body weight; ECF = 50% of TBW, ICF = 50% of TBW. ECF divided into plasma volume (8% TBW), IF (37%TBW), and TF (5%TBW). Blood volume can be approximated as 10% body weight, plasma volume as ½ blood volume. Normal blood volume is 90mls/kg in dog, 50mls/kg in cat, 75mls/kg in horse. Blood loss exceeding 20-25% blood volume can lead to shock.
Blue Tongue Virus - Orbivirus carried by Culicoides. Endemic in USA. Disease of sheep, cattle, goats, and wild ruminants. Cattle are the reservoir. Inappetance in cattle and goats, severe disease in sheep and deer.
• Clinical signs - Sheep- hyperemia of muzzle, lips, ears; dyspnea, erosion/ulceration of oral mucosa; muscle necrosis, cyanotic tongue. Abortions, congenital defects. Mortality 0-30%. Cattle - usually asymptomatic. If develop clinical signs, same as sheep. If infected during gestation, may abort or give birth to abnormal calves.
• Diagnosis and Prevention – IFA. Vaccinate sheep. Insect control
Bog Spavin - Chronic synovitis in tibiotarsal (hock) joint causing obvious distension of joint capsule.
Bone Blood Supply - Diaphyseal nutrient artery enters and passes through cortex to medullary cavity w/out supplying collaterals to the cortex. Divides into ascending and descending branches which anastomose with the epiphyseometaphyseal vessels to supply the BM and compact and cancellous bone. Blood flows centrifugally through cortex to exit via periosteal venules. In areas of the cortex with heavy fascial attachment, the outer 1/3 of the cortex is supplied by periosteal arteries.
Bone Repair - Sequence of events: trauma - local blood vessel damage, local necrosis of bone and soft tissue back to sites of intact vascular perfusion. Active hyperemia to help with fracture healing. Removal of necrotic tissue and bone. Clot organization. Formation of callus. Fibrous callus appears 4-5 days after fracture. Bony callus visible radiographically 11-38 days after fracture. Remodeling of callus. Trabecular bone converted into compact bone between ends of bone fragments.
Bone Spavin – DJD of hock joint terminating in the formation of exostoses and ankylosis of the joint.
Bordetella bronchiseptica :
Pigs One of the causes of Atrophic Rhinitis (atrophy of the turbinates). Pure B. bronchiseptica infections are self-limiting. (lesions heal and there is little to no effect on performance or growth). Piglets infected soon after birth from carrier dam. When infected with pasteurella multocida, will result in atrophy of the nasal turbinates. B. bronchiseptica also causes whooping cough.Carried in the nasal cavity of an asymptomatic carrier sow. Horizontal transmission among piglets may occur. Clinical disease occur in very young piglets. The organism colonizes bronchi and bronchioles. Endotoxins and exotoxins diffuse into the lung tissue causing vascular damage and fibrosis. Mortality up to 30%. Anterioventral hemorrhagic consolidation in a lobular pattern (checkerboard). Dx: bacterial culture. Tx with oxytetracycline, sulfonamides and others.
Dogs May act as primary pathogen in infectious tracheobronchitis (kennel cough), especially in young dogs < 6mo. CS: harsh, dry cough followed by retching and gagging. Highly contagious, but self-limiting. Tx: good management, cough suppresants.
Borreliosis – Tick-born bacterial disease of domestic animals and man. See Lyme Disease.
Botulism - Ingestion of Clostridium botulinum toxin or via wound. Neurotoxin. Prevents synthesis of acetylcholine at motor end plates. Clinical signs are weakness, flaccid paralysis w/ intact pain perception. Progressive. Disturbed vision, difficulty chewing and swallowing, generalized progressive weakness. Shaker foals. Death is due to respiratory or cardiac paralysis. Difficult to isolate organism. Once bound to nerves, antitoxin will have no affect.
Bovine Corona Virus – Neonatal Calf Diarrhea. Winter dysentery. Fecal-oral w/ possible respiratory transmission. Can cause diarrhea in HUMANS.
Bovine Leukosis Virus – Retrovirus. AKA lymphosarcoma, malignant lymphoma, leukemia. Common cattle disease, 2nd most common bovine neoplasia after SCC. Transmitted by transfer of blood b/w animals. Trauma and surgery most common mechanisms of transmission, also insect vectors. Only 3-5% of those infected get LSA.
• Clinical findings - 4 syndromes- calf, thymic, skin and adult forms. The first 3 are not contagious; the adult form is from BLV. Calf form - calves < 6 mo old; widespread tumor metastasis. Thymic form – 6-8 mo old calves. Skin leukosis - only nonfatal form, seen in young adults; superficial cutaneous tumors regress after a few weeks. Adult form - adults 4 -8 yrs old, wide distribution of metastasis.
• Diagnosis - Clinical signs. Serologic test for BLV (adult form only). Severe lymphocytosis (>30,000) is not enough to dx LSA, need histologic dx.
• Control - No treatment. Test for BLV and cull positive animals or segregate all BLV reactors from nonreactors.
Bovine Respiratory Disease – BRD, Shipping Fever. Mannheimia (pasteurella) haemolytica is smoking gun, others involved. Common disease of stocker and feedlot calves. Huge economic impact to beef cow industry. Stress, host, agents and environment all affect. Preconditioning to minimize. Tx w/ Ceftiofur (no w/d time), enrofloxacin, tilmicosin (not in dairy cattle, 28d w/d in beef).
Bovine respiratory syncytial virus RNA= pneumovirus - paramyxovirus family. Is an important part of Bovine respiratory disease complex since it facilitates secondary bacterial infection.morbidity high, mortality 0-20%.CS: Fever, depression, decreased feed intake, increased respiratory rate, cough, and nasal and lacrimal discharge. Dyspnea increased in later stages of the disease.Sometimes subcutaneous emphysema. Diffuse interstitial pneumonia with subpleural and interstitial emphysema along with interstitial edema.
Dx: immunoassay, virus isolation (difficult).Tx: Abs to control secondary bacterial infections, NSAIDs, supportive therapy
Bovine Spongiform Encephalopathy – Mad Cow Disease. Progressive, fatal, neurologic diz of adult domestic cattle. Resembles Scrapie in sheep. 1st dx in Britain in 1986. Caused by prions. Prion agents cause Creutzfeldt-Jakob diz of man, although no evidence that diz acquired from animals. Transmitted by food-borne exposure to agent via contaminated meat and bone meal.
• Clinical signs – Subtle initially, behavioral. Progress over weeks to mos, trigeminal nn signs (licking, sneezing, head rubbing, tooth grinding). Exaggerated responses, frenzy, kicking, startle response. Terminal state usu w/in 3 mos w/ general hypokinesis, salivating, gait ataxia, falling, paresis. Intense pruritus of trunk seen in sheep Scrapie does not occur.
• Diagnosis – Definitive dx requires histologic exam of hindbrain.
• Treatment and control – No effective tx. Ruminant derived proteins are prohibited in ruminant rations in Britain.
Bovine Viral Diarrhea – Flaviviridae. Pestivirus. RNA virus, tremendous amounts of variants, mutates frequently. Respiratory diz in feeder animals, repro dz in pregnant cows. Most common in calves 8-24 months old when maternal antibodies have declined. Endemic, 85-90% of cattle seropositive. Also other farm and wildlife spp. Cytopathic or noncytopathic. Infection of fetuses w/ noncytopathic strains results in persistent infection and immunotolerance. PI calve only created in utero. These calves important in perpetuation of disease, as they are seronegative (don’t have Ab response)and shed lots of virus. Harbored in WBCs.
• Clinical findings - Infection usually subclinical. Fever, anorexia, depression, erosions and hemorrhages of the GIT, diarrhea, dehydration. Oral lesions common, respiratory signs. Infections during pregnancy results in abortion, weak calves, or calves with congenital infections. Infection 120 - 150 days gestation results in congenital defects such as cerebellar hypoplasia, eye problems, hydrocephalus, tight curly coats.
• Diagnosis - Hx, clin signs, paired serum samples, IFA. PCR ear punch test. Virus isolation
• Control and prevent – Test and eliminate. Vaccine. Do not run pregnant sheep with cows since BVD may result in Border Disease. Biosecurity. Good nutrition.
• Acute Infection – subclinical, peracute, hemorrhagic syndrome, repiratory diz, venereal infections. Occurs when naïve cattle are exposed to PI cattle.
• Mucosal Disease – Acute, chronic, diz w/ recovery, delaye onset. Result of chronic or PI of noncytopathic BVDV w/ “super infection” by cytopathically related type.
• Fetal Infection – Abortion, stillborn, congenital defect, PI, normal calf born seropositive.
Bowel adenocarcinoma (cats) Most commonly in the SI of cats. Lymphoma is the most common intestinal tumors of cats. adenocarcinomas most commonly occur in the jejunum and ileum and can be annular or luminal.May metastase to abdominal serosa, lymph nodes, lung, and liver. Clinical signs: vomiting, diarrhea (melena), and weight loss; tumors of the colon are associated with tenesmus and hematochezia. Microcytic anemia due to chronic bld loss.Dx: radiography, ultrasonograhy and intestinal biopsy.anemia, hypoprotenemia and elevated serum hepatic enzyme concentrations.Tx: solitary intestinal tumors can be surgically resected with margins of at least 4 cm.
Bowed tendon/tendonitis/desmitis : Acute or chronic, with varying degrees of tendon fibril disruption. Most common in racehorses. flexor tendons, usually of forelimb is affected. In racehorses, the superficial flexor is involved most frequently. The primary lesion is a rupture of tendon fibers with associated hemorrhage and edema. CS: Severe lameness in acute stage and involved structures are hot, painful, and swollen. In chronic cases, there is fibrosis with thickening and adhesions in the peritendinous area. The horse with chronic tendinitis may go sound while walking or trotting, but lameness may recur under hard work. Dx: Ultrasonography Tx: Best treated in the early, acute stage. Stall rest, support or immobilization, cold packs and systemic anti-inflammatory agents.. Intratendinous corticosteroid injections are contraindicated. When a distinct hypoechoic or anechoic core lesion is present on ultrasound examination, tendon splitting is recommended (to decrease intratendinous pressure due to serum or hemorrhage).Slow return to exercise. Superior check ligament desmotomy maybe used to prevent recurrence. Annular ligament desmotomy is also used when tendinitis involves the area of the digital tendon sheath.
Brachycephalic issues The respiratory system –stenotic nares (surgical correction), elongated soft palate, tracheal stenosis, heat stress- brachycephalic dogs are inefficient panters. Eye problems-Very shallow bony eye sockets, even minor trauma will result in the eye popping out and requiring surgical correction. Sometimes eyelids do not close all the way, leading to irritation and drying of the eye – surgical correction. Other concerns – Abnormal, crowded teeth, resulting in periodontal disease. Skin fold pyoderma, Dystocia due to broad head of pups. Tracheal stenosis.
Brackenfern - Contains thiaminase. Causes thiamine deficiency in nonruminants, esp horses. Polioencephalomalacia in sheep dt impaired thiamine metabolism. Aplastic anemia in cattle.
• Clinical findings - Thiamine deficiency in horses - anorexia, incoordination, crouching stance. Cattle - acute hemorrhagic syndrome, clots in urine, hematuria, pink milk. Chronic enzootic hematuria.
• Diagnosis - Blood thiamine levels.
• Treatment - Thiamine supplementation. Whole blood transfusion. N-betyl alcohol.
Brain tumor (dogs) : Primary brain tumors common in dogs > 2 yrs old of the brachycephalic breeds (gliomas most common). Secondary brain tumors extending from nasal sinus or as a result of metastases from tumors in the other parts of the body. Meningiomas are the most common intracranial tumor in dogs and cats. Pituitary tumors maybe of the functional or nonfunctional type. Functional tumors cause pituitary dependent hyperadrenocorticism (PDH).Dx: radiography, myelograms, scintigraphy, MRI, etc.
Prognosis is guarded to poor. Tx: surgical excision and/or chemotherapy and/or radiation
Breeding soundness in bulls :. A breeding soundness examination consisting of a thorough physical examination, measurement of testicles, and microscopical examination of semen should be conducted ~1 mo before the breeding season. Scrotal circumference is related to amount of sperm producing tissue, number of normal sperm and age of puberty of the bull and female offspring. Minimum sperm motility is 30%, minimum sperm normality is 70%. Primary Sperm Abnormalities include Underdeveloped. Double Forms, acrosome defect, narrow heads, crater/diadem defect, pear-shaped defect, abnormal contour, small abnormal heads, free abnormal heads, abnormal midpiece, proximal droplet, strongly folded or coiled tail, accessory tails. Secondary Sperm Abnormalities include Small normal heads, Giant and short broad heads, Free normal heads, Detached, folded, loose acrosomal membranes, Abaxial implantation, Distal droplet, Simple bent tail, Terminally coiled tail.
.Bronchitis: Chronic bronchitis most often affects small breeds of dogs and is characterized by persistent cough for at least two consecutive months in absence of specific pulmonary disease. Cough lasts for 2-3 days. In chronic bronchitis, chest radiographs may show an increase in linear and peribronchial markings. Bronchoscopy reveals inflamed epithelium and tacky, often mucopurulent mucus in the bronchi. Eosinophils may be revealed in bronchial washings. Tx: antibiotics, supportive therapy and cough suppressants
Brucellosis – Bacterial infection of cattle, pigs, sheep, goats, dogs, people, horses. ZOONOTIC. Characterized by abortion, retained placenta, and orchitis.
• Brucellosis in cattle - Brucella abortus is #1; also B. suis, B. melitensis. AKA Contagious abortion, Bang’s disease.
o Transmission - Via ingestion of organism, venereal, mechanical transmission. Organism present in aborted fetuses, membranes, uterine discharges. Can also enter body through mucous membranes, conjunctiva, wounds, intact skin.
o Clinical findings – ABORTION. Also retained placentas, reduced milk yield, orchitis.
o Diagnosis - Bacteriology or serology. Serum agglutination is standard test. ELISA to detect antibodies in milk and serum. Best recovered from stomach/lungs of aborted fetus.
o Screening test procedures - Brucella milk ring test, pooled milk samples tested. Market cattle testing - serum testing of cattle sent to slaughter.
o Control - Test and eliminate reactors. Vax w/ Strain 19 or RB51. Usually vax heifers only. All dairy animals must be vaccinated at 4-8 mos of age. Vax of beef heifers is optional at 4 - 12 mos of age. Do not vaccinate any animal over the max age. ID vax calves by tattoo and eartag. Place tattoo and official orange eartag in R ear. Precede shield with letter corresponding to quarter of the year (A, B, C, D). The shield should be followed by the number corresponding to the last number of the year.
• Brucellosis in dogs - Brucella canis. 3rd trimester abortion – orchitis. Also B. abortus, B. suis, or B. melitensis associated with infected domestic livestock.
• Brucellosis in sheep - Brucella melitensis, abortion. B. ovis, produces disease unique to sheep. Epididymitis and orchitis impair fertility.
• Brucellosis in pigs – B. suis. Usually self limiting, can remain in herd for yrs. Man working in pack houses at risk. Prevalence highest in feral pigs. Brucellosis card test. No vax.
• Brucellosis in horses – B. abortus, B. suis. Suppurative bursitis, “fistulous withers” or “poll evil”. Occasionally abortion. Unlikely source for disease to other horses, animals or man.
• Brucellosis in people – Undulent Fever. Usu mild, can be serious public health problem esp when B. melitensis.
Bucked shins: Inflammation and swelling on the front of the shin (Bucked Shins). Metacarpal periosteitis..May result from concussion of the hoof hitting the ground, hemorrhage and stress fractures, especially young horses trained too fast and too hard. The body responds to hard training by thickening the front of the shin bone (third metacarpal), but if training progresses too quickly, the body cannot keep up with the bone remodeling process and microfractures and hemorrhage develop. If training is continued, a callus will form. Initially the horse will be reluctant to finish a training exercise. Swelling begins over the metacarpus and palpation is painful. Lameness (usually in both legs) follows.Dx: physical examination using palpation of the cannon region in which heat, pain upon pressure over the area, and swelling is detected over the dorsal or dorsomedial surface. The horse may be short-strided or lame. Radiographs may also show changes but may lag the clinical signs. Radiographic changes include new bone formation on the [periosteal] surface and thickening of the front of the cannon bone.
Tx: Short rest with slow return to exercise and systemic and topical anti-inflammatories (phenylbutazone) and physical therapy.. Surgical internal fixation is recommended in some cases. Prior to resuming training reshoe with corrective shoes with padding, lowering the heels and eliminating toe grabs. A soft training surface is better than a hard track when training resumes.
Bullous diseases – Autoimmune diseases of skin and mucous membranes characterized by pustules, vesicles, bulges, erosions and ulcerations. Occur in dogs, cats and horses.
• Pemphigus foliaceus – Young to middle aged dogs uncommonly, even less so in cats and horses. Pustular crusting disease sparing mucous membranes (no lesions in mouth). May form widespread heavy crusts, marked hyperkeratosis of footpads, and involvement of nailbeds that may lead to loss of the nails. Tx with high doses of immunosuppressive drugs.
• Pemphigus vulgaris – Less common than PF. Vesicular disease affecting mucous membranes. Blisters, vesicles (rupture quickly), erosions in mouth, rectum. Suprabasilar acantholysis. Tx with high doses of immunosuppressive drugs. Difficult to get into remission. Poor px.
• Bullous pemphigoid - Collies, DPs. Rare, sloughing diz. Lesions widespread, tend to concentrate in groin. Resembles severe scald. Below basement membrane (no acantholysis). Pred + Azathioprine. Remission frequent w/ LT drug tx. LT px poor.
• Pemphigus erythematosus – Affects face and ears, has features of DLE. Scaling lesions, hypopigmentation of the planum nasale. Not well defined.
• Pemphigus vegetans – Rare. Benign variant of pemphigus vulgaris. Bullae replaced by verrucoid hypertrophic vegetative masses.
• Discoid Lupus Erythematosus – Dermal SLE. Autoimmune skin disease of dogs characterized by depigmentation, erythema, scaling, erosions, ulcerations and crusting, particularly on and spreading up the bridge of the nose, and sometimes the face and lips. Immunoglobulins and/or complement are deposited at the basement membrane in the skin. Tx w/ tetracycline/niainamide promising.
• Systemic Lupus Erythematosus – Controversial. Multisystemic autoimmune disease of dogs and cats. Extremely wide variety of clinical signs may occur, but immune-mediated polyarthritis, hemolytic anemia and skin disease are most common.
Burns: Electric burns or from hot objects. If fur comes off easily from the burnt spot, condition is serious. First degree burns – only epidermis. Second degree burns – epidermis and some part of dermis – blister formation and discoloration. Third degree burns – all skin layers. Skin grafts are required. loss of capillary endothelial integrity results in leakage of fluid and tissue edema, hypovolemia, shock, DIC, ventricular arrhythmias and neurogenic pulmonary edema (electrical), hemolysis, mucosal damage and tissue edema (inhalation),renal damage (due to hypovolemia, hburia, and myoglobinuria), GI dysfunction (from increased intestinal permeability, and immune dysfunction from loss of immunoglobulins. Tx: ABCs, wound management, pain management, antibiotics, fluids (1 ml/kg X% Total Body Surface Affected (TBSA)
Calcium Deficiency – Nutritional 2 hyperparathyroidism. More commonly dt PO4 or vita D deficiencies, also excessive Ca:PO4 ratios. Hand fed baby birds and iguanas, indoor pigs on processed feed, big cats fed only meat. Rickets in young or osteoporosis in adults. Folding fractures in bones, spinal cord compression, seizures. Tx non-irreversable damage w/ dietary correction.
Calcitriol – Synthesized in kidney. Acts on intestine and kidneys to maintain normal calcium levels.
Calf Diarrhea – “Calf Scours”
o E. coli (enterotoxigenic, enteropathogenic)
o Clostidium perfrigens
o Campylobactor fecalis, C. jejuni, C. sordelli
o Giardia (rare)
o Milk malabsorption (bicarbonate fluids PO)
o Milk replacers
CS: diarrhea, dehydration, acidosis, depression/weakness, lose suckle reflex, recumbancy & coma, hypothermia, cachexia, death.
Dx: impossible on CS alone. Lab on feces or tissue, Necropsy, response to therapy.
Tx: isolation. Fluids & electrolyes (BW x %dehydration = L), Broad Spec Abs, Check for Failure of Passive Transfer plasma or blood transfusion.
Px: Environ hygiene, no nose-to-nose contact, handle sick animals last, Colostrum! W/in 1st 2 hrs of life. 10%BW w/in 12 hrs.
Public Health: Salmonellosis & Cryptosporidiosis
Calf Diptheria – Necrotic Laryngitis. Fusobacterium necrophorum. Necrotizing edotoxin. CS: moist, painful cough, severe inspiratory dyspnea w/ open-mouth breathing & head and neck extended, ptyalism, bilateral purulent nasal discharge, fetid breath odor, fever (106oF/ 41.1oC). Lesions: necrotic ulcers of the larynx (behind vocal cords on vocal process of arytenoids). Dx: based on Hx, CS, Laryngoscope. Tx: Sulfonamides, NSAIDS, isolation, & support. Treat Early & Aggresively!
Campylobacteriosis (Bovine) – Campy. fetus fetus or C. venerealis. Causes infertility/ early embryonic death. Transm.- Coitus. Bulls maybe subclinical carriers. Dx: FAB from preputial cavity and fornix swabs. inoculate into Clark’s media. Demostration /isolation or org. & view under darkfield microscope (curved rod w/ darting corkscrew motility. Mucus agglutination test to survey herd infexn. Tx: Vacc asap when genital campy dx’d. Treat bulls w/ streptomycin. Avoid by AI.
Camplobacter (dogs)– Acute enteritis in dogs. Bloody diarrhea. ZOONOTIC. Transmissible to people.
Candidiasis (Pet Birds) – Candida albicans. Opportunistic yeast infection of GIT. Most commonly infects weaned chicks. Cs: delayed crop emptying and thickened crop. Dx: cytology. Tx: eliminate exogenous candida source. Empty crop and feed smaller portions in neomates. Nystatin PO.
Canine distemper (dogs)– Paramyxovirus. Affects both old & young dogs. Initial respiratory signs, GI and CNS (chewing gum fits) signs may follow. Hyperkeratosis of the footpads and nasal planum. Suspect in any febrile condition in puppies or multifocal neurologic dse. Febrile catarrhal illness with neurologic sequelae justifies dx of distemper. IFA of epithelium, buffy coat, necropsy.
Canine Distemper (Ferrets) - Trans: aerosol or infected secretions exposure. CS: seen 7-10 days post exposure. Fever, dermatitis on chin & inguinal area, anorexia, erythema of mm, mucopurulent nasocular discharge, brown crusts on face & eyelids, hyperkeratosis of footpads. Respiratory signs develop and rapidly progress. Dx: by Hx, CS, + IFA, or histopath. Mortality almost 100% & typically occurs 12-14 days post infxn.
Canine parvovirus - Viral gastroenteritis, paralysis and ileus of intestines. Wipes out intestinal crypts causing villous atrophy secondarily. Transmission is fecal-oral. Survives in environment for years. Bleach is only effective disinfectant. Salmonella mimics. Major cause of intussusception in dogs.
• Clinical Signs – Most infections clinically inapparent. Vomiting seen 1st, diarrhea later. Leukopenia can be seen.
• Diagnosis – Parvo Site test (can be false- if early in infection). Rads, can appear as obstruction w/ dilated intestines.
Treatment – IV fluids, antibiotics, antiemetics.
Capillaria aerophila - Respiratory parasite of carnivores. Ingestion of larvated eggs. Eggs hatch in intestine, larvae reach lungs via circulatory system. Eggs layed in lungs, coughed up and swallowed. Clinical signs include coughing, sneezing, and nasal discharge. Diagnose w/ fecal float, see eggs with bipolar plugs. Treat with levamisole, fenbendozole.
Capillaria plica - Bladder worm. Found in kidney, ureter, bladder of dogs, cats. No clinical signs. Earthworm host. Eggs passed in urine. Treat with fenbendozole, ivermectin, levamisole.
Caprine Arthritis & Encephalitis– Lentivirus (non-oncogenic retrovirus) of goats. Arthritis in older goats, neurologic diz in goats < 1y.o. Adult dairy goats get chronic arthritis and mastitis. Young get leukoencephalomyelitis, ascending paralysis. Transmitted through milk and colostrum. Most goats are infected young, carry virus and develop years later. Dx: serology, AGID or ELISA. Px: - feed baby goats pasteurized milk. Test and cull.
Carbohydrate Engorgement - fermentable feedstuff, new carbo diet (pasture). Rumenal organisms proliferate and cause ceased motility. Bloat, splashy rumen. Fluid shifts into rumen = dehydration. Rumen ph < 5.5, sour. Tx w/ oral antacids/carmilax. Remove grain.
• Sinus arrhythmia - Normal in dogs, uncommon in cats.
• Sinus bradycardia - Caused by increased vagal tone. Treat with atropine, glycopyrrolate, isoproterenol, artificial pacemaker.
• Sinus tachycardia - Caused by atrial enlargement, stress response. Treat underlying cause. Placing pressure on eyeballs will induce vagal response, slow heart rate.
• Heartbeat :
o S1 = Signals closure of AV valves and start of systole
o S2 = Signals closure of semilunar valves and end of sytole
o S3 = Heard if venous return; pregnancy
o S4 = Assoc w/ atrial contraction. Immediately precedes S1. Can be heard in horses.
Cardiac Arrythmias (Equine) – always note:
1. Vetricular Rate (normal, bradycardic, tachycardic)
2. Rhythm of 1st and 2nd heart sounds (reg or irreg)
3. Presence of dropped or premature beats
Most common equine arrythmias:
Clinical Findings ECG Findings
2nd-degree AV block Slow/norm heart rate.
Regulat irregular rhythm w. occasional dropped beats.
Isolated S4 sounds.
Pulse deficit. Occasional P wave not followed by QRS.
Sinoatrial block Slow/norm heart rate.
Regular rhythm w. long pauses. Regular underlying rhythm w/ absence of P waves for > 2 PP intervals.
Sinus arrhythmia Slow/norm heart rate.
Variable S1-S1 interval. Variable RR interval ± wandering pacemaker (variable P-wave morphology).
• Heart Block – Middle aged, older dogs. vagal tone dt drugs, endocarditis, DCM, HCM, hyperkalemia. If high grade, may see syncope, exer intol, weakness. On ECG, HR, P w/ no QRS, large T. 1st, 2nd or 3rd (complete) degree. Long term mgmt in pacemaker. Do not give antiarrythmic drugs, may suppress escape rhythm.
• Sick Sinus Syndrome – Female mini schnauz, dachs, cocers, pugs. May see w/ supraventricular tachyarrythmias. Episodic weakness, syncope. ECG, sinus bradycardia, sinus arrest, SA block. HR goes from 220 to 0 and back to 220. Permanent pacemaker reqd for LT tx. Asymptomatic dogs w/ abnormal ECG do not require tx.
• Supraventricular Tachycardia - Atrial premature contractions, paroxysmal atrial tachycardia, atrial flutter, atrial fibrillation. Dt atrial diz, enlgd atria (MR, DCM), CHF, digitalis toxicity. HR>180. May or may not be hemodynamically significant. “Regularly irregular.” ECG, normal, narrow QRS. Tx w/ vagal maneuver to restore sinus rhythm. Also, blocker, Ca++ channel blocker. Digoxin for chronic, LT tx.
• Atrial Fibrillation – Dogs>cats. Assoc w/ MR, DCM, GDV, anesth, heatstroke, trauma. Rapid, irregular pulse w/ chaotic rhythm. “Irregularly irregular.” ECG, chaotic pattern w/ no demonstrable P waves on any lead. Can’t cure. Slow ventricular response rate so heart can fill better. blocker, Ca++ channel blocker. Digoxin for chronic, LT tx.
• VPC – Dt myocarditis, DCM, lyte disorders, trauma. Rarely hemodynamic signif unless frequent, then see hypotension, acid/base disturbance. ECG, bizarre QRS > 3 consecutive beats not preceded by normal P wave. HR > 160-180. Eliminate clinical signs and prevent sudden death. IV lidocaine or procainamide and O2 admin.
• Valvular Heart Disease – Geriatric, small breed dogs w/ murmur. Ddx trach collapse, COPD, bronchial diz, endocardiosis, heartworms, neoplasia. Nonprod, honking cough, thin, weak, rapid pulse, tachyarrhythmia. Dx w/ thor rads. LA, LV enlgmt (VHS>10.5). Echo, see thickened, nodular valve. Tx depends on severity. ACE inhibitors, Na+ restricted diet. Add diruetics if edema. digitalis, cough suppressants, bronchodilators.
• Pericardial Disease – Congenital, infectious, idiopathic, neoplasia (GSD, GR, Box, Bull). Diastolic heart dysfxn. R CHF, abdominal distention, jug venous disten, pleural effusion. NO murmur, gallop or arrhythmia. Muffled heart sounds. Rads, see huge, globoid heart. Echo, see echo free space b/w myocardium and pericardium. ECG, may see electrical alternans. Pericardiocentesis. Avoid diuretic and vasodilators.
• HCM – Cats, middle aged males. Diastolic heart dysfxn. Pale mm, jug venous dist, lack of femoral pulse, murmur, gallop. Rear limb paralysis, pain. Usu no arrhythmia. Echo is definitive, enlgd heart at expense of lumen. Relax and slow heart w/ blocker (atenolol), Ca++ channel blocker (diltiazem). Oxygen. aspirin, furosemide. No digitalis, pump is OK.
• DCM – Large breed dogs, male>female, 2-5 y.o. DP, GSD, St.B, Irish wolf. Cockers also. Rare in cats unless taurine deficiency. Systolic dysfxn. Coughing, wt loss, weakness, ascites, syncope, ADR. Weak femoral pulses, arrhythmias (atrial fib and Vtach), gallops, jug venous dist. Rads, pulm vv and caudal vena cava enlgd, pulmonary edema. Echo, dilation of atria and ventricles. afterload and augment contractility. ACE inhibitor (enalapril). Digoxin, blocker. Diuretic if congested, procainamide if vtach.
• ACE Inhibitors – Inhibit angiotensin I angiotensin II and production of aldosterone. peripheral vasoconstriction and Na+ and H2O retention. Afterload and preload reducers. Vasodilation and reverse remodeling. The “–pril: drugs - Enalapril (Enocard), used for DCM, prodrug activated in liver, renal clearance. Benazapril same by hepatic clearance and SID. Side effects include renal failure ( GFR), hypotension. Do not use in conjunction w/ NSAIDs (like Rimadyl).
• Hydralazine – Pure arteriolar vasodilator. Potent afterload reducer, BP. Indicated for chronic valve diz and DCM. Must titrate dose. Side effects include hypotension and HR.
• Amlodipine – Ca++ channel blocker. Arteriolar vasodilator. Treat hypertension in cats (w/out heart diz) and in conjunction w/ ACE inhibitor in dog for more afterload.
• Nitroglycerin – Preload reducer, venous capacitance. Emergency use for CHF, blood in shunted to capacitance vv.
• Procainamide – Membrane stabilizer. Slowed conduction, less automaticity. IV emergency tx of ventricular arrythmias.
• Lidocaine – Membrane stabilizer. Emergency tx for ventricular arrythmias. IV, short t½, so slow IV drip.
• Propanolol – Class II blocker. Negative chronotrope and inotrope. For atrial tachycardia and HCM to heart and filling time. Side effects include bronchoconstriction, bradyarrythmias, hypotension, heart failure, hypoglycemia.
• Atenolol – Class II blocker, specific to 1. Don’t see bronchiolar effects.
• Diltiazem - Ca++ channel blocker. Negative chronotrope and inotrope, conduction. Atrial tachycardia and HCM.
• Digoxin – Cardiac glycoside. Positive inotrope, negative chronotrope. Supraventricular tachycardias, CHF, DHF. Side effect is arrhythmogenicity, N, V, D via stimulation of CRTZ. Dose on lean body weight.
• Positive Inotropes:
• Dobutamine – Direct 1 stimulation. Positive inotrope and chronotrope. Emergency CHF. CRI. Arrythmogenic.
• Epinephrine - 1, 2, 1, 2 stimulation. Potent vasopressor dt positive inotrope and chronotrope. Emergency tx of cardiac standstill. Very arrythmogenic.
• Furosemide – K+ wasting diuretic, use when congestive diz. See Diuretics.
• Spironolactone – Antialdosterone diuretic; blocks effects at distal tubules, spares K+, eliminates Na+ and Cl-. Not potent by itself, use in combo w/ other diuretics. Good for ascites. Careful in combo w/ ACE inhibitor. Also has reverse remodeling effects on the heart, antifibrotic.
1. Dilated Cardiomyopathy (DCM) Taurine deficiency
2. Hypertrophic Cardiomyopathy
3. Restrictive Cardiomyopathy
CS: acute heart failure; dyspnea, murmurs (gallop rhythm)
Rads: left atrial or bilatrial enlargement. DCM: ventricles enlarged too. Hypertrophic cardiomyopathy and sometimes Restrictive cardiomyopathy: valentine-shaped heart on DV view.
Meds: Furosemide, Diltiazem, ACE inhibitors, Digoxin, Propanolol
Cardiovascular Disease in Equine – Most common congenital defect is VSD. Loud R systolic murmur. PDA continuous murmur normal for 1st week of horse’s life. Acquired valvular disease dt rupture tendinae, hypertension, endocarditis. 1st most common is aorta, then mitral, then tricuspid (cows get it at tricuspid valve). Can often hear physiologic flow murmurs, II/VI is normal esp in athletic horse. Most common arrhythmia in horses is atrial fibrillation, irregularly irregular beat, tx w/ quinidine. 2 AV Block fairly common finding, can hear extra heart sound. Increase heart rate (exercise) and should go away. Heart failure – lasix and digoxin.
Carnassial Tooth Abscesses (Canine) – Et. Localized abscess formation involving the roots of the carnassial teeth (upper 4th PM or lower 1st M). CS: most often affects upper 4th premolar. Infection can extend into nasal sinus (may note unilateral nasal discharge) or maxillary sinus (may note draining sinus on face just below eye). Dx: Rads.- radiolucent area around root. Tx: extraction (or endodontic repair), supportive care (Systemic ABs 2 weeks).
Carpus Valgus – In foals usually in conjunction with fetlock varus. Tx w/ periosteal stripping (on side want to grow faster), growth plate reduction, physeal intervention.
Caseous Lymphadenitis - Corynebacterium pseudotuberculosis. Caseous abscessation of lymph nodes and internal organs in sheep and goats. Also in equine and bovine. Infection via contamination of open skin wounds. Diagnosis via abscess aspirate or serology (Synergistic Hemolysin Inhibition Test). Infected for life. Herd strategy is to cull then leave pasture empty for 6 mos. Can lance and flush abscesses - frequent recurrence. Can treat with NaI and penicillin to keep from getting worse (not to cure). ZOONOTIC, wool workers get from shearing nicks.
Castor Beans - Extremely toxic, contain Ricinus communis (ricin). Violent purgation, straining w/ bloody diarrhea, weakness, salivation, trembling, incoordination. All spp effected, cultivated in south. Potential bioterrorism weapon.
Castration (Bovine) – Small Calves: remove bottom 1/3 of scrotum w/ scalpel. Larger cattle: scalpel or Newburry knife incise from above testicle to dist. scrotum. Pull out testicle surrounded by vaginal tunics (closed cast). Emasculator high on spermatic cord. “Nut to Nut” of emasculators, make sure cutting edge is distal to crushing. Maintain crush for 1-2 mins. Leave wound to granulate in. Emasculotome does not leave wound.
Castration (Porcine) – separate incisions made into each testicle. And the tunic attachments are broken. The testicle is either pulled away by traction endeavoring to break the blood vessels and cutting the vas deferens or the complete spermatic cord. After, raise skin incision to ensure to tissues remain exposed. Pigs over 5 weeks require local anesthesia.
Castration (Equine) – most horses presented for castration @ 2 yrs. May be Standing or Recumbant under Gen. Anesth. Most common complication from standing castr is excessive swelling around penis & prepuce because the incision in the scrotum is too small and does not permit adequate drainage. When recumbent, the castration is most easily performed for Right-handed operators with the horse lying on its Left side.
Cat Scratch Fever - Benign lymphadenitis of HUMANS believed to be caused by infectious agent, Bartonella henselae, B. quintana. Usu assoc w/ scratch or bite from cat.
Cataracts (dogs) Opacity to the lens of the eye or its capsule. Surgical removal of lens. Dogs more commonly than other species. Cats and horses, most cataracts 2 to inflammation. Congenital and acquired, juvenile onset, adult onset.
Cataracts (Equine) – congenital cataracts are more common & more amenable to Sx Tx than acquired cataracts. Pupillary dilation is essential to asses the extent of the cataract & to allow fundic examination to evaluate signs of equine recurrent uveitis.
Cauda Equina Syndrome – Group of signs w/ several etiologies. U/F incontinence, posterior ataxia, hypo/anesthesia of tail and perineum, penile paralysis. Progressive. Dt EHV1, strep ag, EPM. Euthanize, do not get better. Ddx is fractured sacrum.
Cecal Disorders (Bovine) – Cecal dilation & volvulus. Assoc w/ parturition or Δ to concentrate from roughage. Distention leads to volvulus ( twisting of cecum & prox loop of ascending colon.)
CS: Dilation - ↓ feed intake, ↓ milk prodxn, mild abdo pain, distended R paralumbar fossa, still passes feces. Volvulus – Abrupt CS, R paralumbar distention, anorexia, agalactia, marked abdo pain, tachycardia, forestomach stasis, manur scant or absent.
Tx: Dilation – antacids/laxatives Mg(OH)2, IV or oral fluids, course hi fiber diet, no concentrates, IV or SQ Ca in lactating cows, Sx (typhlectomy; remove cecum) if recurrent. Volvulus – Sx necessary, incision cranial R flank, untwist & decompress, see if typhlectomy needed, fluid mngt (K, Cl & alkalosis).
Cephalosporins – G+, some G-, anaerobes. Bactericidal. Beta-lactam antibiotics. Inhibit cell wall synthesis. More effective against actively growing bacteria. See Antiobiotics section.
Cervical Vertebra Malformation (Equine) – cervical stenotic myelopathy, “Wobbler Syndrome”. Et: static stenosis – C5-7. or dynamic stenosis – C3-5. There is a focal compression of dorsal spinal cord. CS: pronounced hindlimb ataxia & parsis. ± spastic forelimbs. “Clumsy Tin Soldier walk w/ knuckling”. Dx;:based on Hx & clumsy CSs. Rads: static compression. Measure diameter of spinal canal & compare w/ normal horse. Dynamic compression – subluxation on flexion of vert jxns. Mylegraphy for suble lesions. Tx: ?? Rare recovery w/ corticosteroids. Sx arthrodesis. Guraded Px.
Chediak-Higashi Syndrome – Blue smoke persians. Oculocutaneous albinism. Bleeding disorders.
Cheyletiella - "Walking dandruff.” Occurs in dogs, cats, rabbits. ZOONOTIC. Likes high altitudes (CO). Highly contagious scaling on dorsal trunk. Moderate to intense pruritus. Alopecia and inflammatory changes 2 to scratching. Treat environment, ivermectin, sulfur shampoo.
Chinchillas – Require regular dust baths to maintain healthy coat and skin. Pans should be provided in cages. Grab by tail.
Chlamydia psittaci – Psittacosis. Common infectious disease of birds. ZOONOTIC. Gives people URT infection, flu-like signs. Signs vary w/ avian spp from subclinical to systemic disease involving respiratory tract and liver, see yellow urates. Very high WBC in birds (ddx Mycobacterium (avian TB), Aspergillosis). Dx via serology (EBA test) or PCR of oral/cloacal swabs. Tx w/ doxycycline.
Chlamydiosis (psittacosis/ornithosis) of Poultry - Chlamydia psittaci. Aerosol transmission. CS: Wt loss, depression, anorexia, diarrhea, lime-green urates, respiratory signs. Hepatomegaly, splenomegaly, air sac changes.
Dx: – ELISA, titers, intracellular elementary bodies on impression smears of air sac, spleen, liver, pericardium. Tx: Tetracyclines -Doxycycline. Reportable. ZOONOTIC.
Chlamydial Polyarthritis (Sheep & Goats) – Transmissible serositis. Also affects calves & pigs. Chlamydophila psittaci. GIT of prime importance in pathogenesis. CS: varying degrees of stiffness, lameness, anorexia & concurrent conjunctivitis. Affected sheep are depressed & reluctant to move. Enlargement of joints NOT noticed except in chronic cases. Joints contain grayish yellow turbid syn fluid. Dx: chlamydial elementary bodies from synovial fluids. Tx: if early enough, long-acting penicillin, tetracycs, or tylosin.
Choke (Bovine & Equine )- Obstruction of esophagus by food masses or FB. Horses choke on greedily eaten dry grains. Bovine; on beets, apples, etc or from Hypoderma lineatum (dead larvae – severe rxn). Localized esophageal dilation, hemorrhage necrosis. Exhibit anxiety, arched neck, retching, salivation. Food, froth through nose. May get aspiration pneumonia. Pull food, provide water, painkillers, sedatives. May pass stomach tube.
Cholangitis/Cholangiohepatitis (Fel)– Common hepatic dse of cats, dogs get also. ALT, SAP, bilirubin. Bx to dx, culture and cytology of bile. Suppurative form dt ascending infection. Has neutrophils; Tx w/ antibiotic such as amoxicillin and/or enrofloxacin. Nonsuppurative form has lymphs and plasma cells. Imm mediated diz, tx w/ prednisolone
Chorioptic Mange – Chorioptes bovis. Most common mange in cattle. Pastern area most common - "leg mange". High proportion of cattle may be infested without exhibiting signs. More prevalent in winter. Non-zoonotic but REPORTABLE, since r/o sarcoptic mange which is zoonotic.
Chronic Active Hepatitis - Group of diseases that tend to progress to cirrhosis. Glucocorticoids indicated in moderate to severe symptomatic autoimmune chronic active hepatitis. They are not indicated in asymptomatic cases, mild cases, or viral-induced disease.
Chronic diarrhea / Granulomatous enteritis (Equine) – aka inflammatory bowel disease. Infiltration of the sm & lrg intests and regional LNs w/ inflammatory cells (lymphos, plasma cells, macros, eosins). Malabsorption & protein-losing enterocolopathy results. CS: ± diarrh. Weight loss, recurrent colic, hypoproteinemia, gen. Skin dse. Dx: based on CS, thickened bowel, enlarged mesenteric LNs, Tx; support. nutritional care, corticosteroids, dietary Δs, metronidazole, azathioprine have been used. Sx may be necessary. Px: grave.
Chronic Interstitial Nephritis (Fel)
Chronic Obstructive Pulmonary Disease “COPD” (Equine ) - heaves, asthma. Allergic rxn thought to initiate. Usu in north when kept indoors. Prevalence w/ age. Inflammation, chronic bronchoconstriction, thickened bronchi. expiratory effort, exercise intolerance, cough. Afebrile. Dx w/ endoscopy, TB asp, thor auscultation of expiratory wheezes. Tx with environmental changes, antiinflammatories, steroids, bronchodilators. Summer Pasture Associated OPD – same but summer, south, in pasture.
Chronic Sinusitis: (Fel) Et: Fel rhinotracheitis (FVR) & Fel calicivirus (FCV) w/ 2o bacterial infxn complications. CS: inspiratory dyspnea, sneezing, nasal discharge. Dx based on Hx. Tx: ABs 3-6 weeks.
Chronic Urticaria - Characterized by transient wheals in the skin or mucous membranes. Most frequently recognized in the horse. Drugs and ingestants are most frequent causes. Treat with corticosteroids, avoidance of the allergens, hyposensitization to inhaled allergens.
Chronic Wasting Disease (Cervidae) – deer & elk. Member of transmissible spongiforme encephalopathy family. Transmit horizontally. CS: animals >16 mos. Wide spectrum of subtle changes. Often die of aspiration pneumonia. Lesion in brain & LN. Dx: detection of prion in CNS or lymphoid tissue via immunohistochem or ELISA. Tx: none. Zoonotic Potential.
Chylothorax: (Fel). Rare. Accumulation of chyle in pleural cavity. Et: idiopathic or rupture of thoracic duct. CS: rapid shallow breathing w/ inspiratory dyspnea, and weakness. High triglyceride [ ] w/ low cholesterol. Dt malignancy, trauma, congenital, pancreatic, parasitic, infectious, idiopathic, lymphangiectasis. Conservative tx is sporadic thoracocentesis, chest tube placement. If fails, pleurodesis (variable outcome). Treat cause (i.e. pericardectomy).
Cirrhosis – End stage liver diz from any cause. Dogs > cats. Cobblestone liver. Cockers risk. See microhepatica on rads, need bx to confirm. Supportive tx, slow progression.
Cloacal Prolapse (Pet Birds) – common in adult Umbrella & Moluccan cockatoos. Et: unknown. ONLY Occurs in birds if:
2. delayed weaning/continued begging for food
3. close attachment to at least 1 person
4. tendency to hold stool for long periods rather than cage defecation.
Does NOT occur in cockatoos independent of humans.
May be dt: (Or combination of these factors)
1. Prolonged begging for food straining & dilation of vent
2. Misplaced sexaual attraction to human straining & dilation of vent
3. Prolonged retention of stool straining & dilation of vent
Tx: Sx & Behavior Modification.
Clostridial Diseases – Anaerobic, spore-forming, exo- or enterotoxin forming.
• Bacillary Hemoglobinuria – C. haemolyticum. Cattle, red water disease. Sudden death, Hgburia.
• Blackleg – C. chauvoei (also septicum, novyi, sordelli). Cattle, sheep. Swelling, hemorrhage, and emphysema in heavy muscles. Rancid butter odor.
• Botulism – C. botulinum. Rapidly fatal motor paralysis by ingestion of carrion and subsequent neuro-intoxication (not infection). Neuromuscular weakness progessing to paralysis.
• Hemorrhagic Enteritis and Enterotoxemia - C. perfringens
• Infectious Necrotic Hepatitis – Black disease. C. novyi + liver flukes. Usually in sudden death in sheep.
• Malignant Edema – C. septicum usually, also chauvoei, perfringens, sordelli, novyi. Farm animals.
• Tetanus - C. tetani. Neurotoxin in necrotic tissue. All mammals (dogs, cats, birds seem resistant). Stiffness, spasms, progressive. Immunization.
Clostridial enterotoxemia (Bovine) – C. perfringens types C& D. Beta toxin – Endotoxin derived from bact cell walls. Hi Mortality. CS: sever enteritis, dysentery toxemia, acute diarrhea, abdo pain, convulsions, opisthonus, Sudden death . Dx: based on Hx (sudden death) necropsy – hemorr enteritis w/ deep blue-purple mucosal ulcerations. Gram stain for G + rods. Tx: usually ineffective if CS. Hyperimmune serum, Abs PO, NSAIDS. Px: vacc preg dam last trimester.
Clostridial Infections (Equine) – see above.
Clostridial Myositis (Bovine) – “Blackleg”, Emphysematous gangrene. Clostridium chaovoei. Also C. septicum and sordelli. An acute febrile disease of cattle and sheep characterized by myonecrosis and emphysematous swelling, usually in the heavy muscles. Caused by ingestion of spores and deposition into muscles. Usually in young adult beef cattle w/ no hx of trauma. Usually trauma induced in sheep. Most common in summer and fall.
CS: - Crepitant swellings of the heavy muscles. Acute lameness. Acute death in healthy young beef cattle.
Dx: - History, clinical findings, IFA.
Tx: Bacterin to susceptible cattle. Prophylactic Penicillin. Debridement & or Fenestration.
Control – Vacc blackleg/malignant edema before Sx. Deep bury or burn carcasses.
Clostridium perfringens (Porcine)- Type C Enteritis. Small Intest infxn causes highly fatal necrohemorrhagic enterits. Commonly affects piglets 1-5 days but maybe seen up to 3 weeks old. Dx: fecal or intest mucosal culture. Tx: rarely successful. Px: vacc w. toxoid.
Club foot – Caused by deep digital flexor contracture. Results in flexion of the distal interphalangeal joint, resulting in a raised heel (club foot). Treat with a distal check desmotomy, corrective shoeing. If nonresponsive, deep digital flexor tendonotomy may be required for salvage.
Cnemidocoptes pilae (Scaly leg Mite) – aka scaly face mite. Common in budgies. Cs: white prous encrustations involving corners of mouth, cere, beak, periorbital areas, legs. In passerines, crusts on legs and digits (Tassel foot). Maybe be dt immunosuppression. Dx: pathognomonic lesions or sckin scrape. Tx: Ivermectin 200-400µg/kg PO or injection. Repeat in 2 weeks.
CNS Trauma (Equine) – usually result from head injuries. May result in basisphesenoid fractures and avulsion of ventral straight muscles of head, as well as optic nerve damage and cerebral signs. May be severely ataxic. Handle w/ Extreme Caution! Dx: based on Rads. Tx: supportive care based on minimizing 2o brain damage. Tx: intubation for hypoventilation. NSAIDS. Corticosteroids if used immediately. DMSO.
Coagulation /coagulopathy – Goal to form a localizeed fibrin meshwork. 3 components necessary for normal coagulation are intact vasculature (trauma, vasculitis), coagulation factors (DIC, rodenticide, liver failure, congenital), and platelets (aspirin, NSAIDs). Most common bleeding problems are dt thrombocytopenia and coag factor deficiency.
• Intrinsic pathway – Starts w/ exposure to abnormal surface. Factors XII, XI, IX, VIII. Factor VIII deficiency is hemophilia A, most common inherited bleeding deficiency in dogs and cats. X-linked, females are asymptomatic carriers, males are affected. Factor IX deficiency is hemophilia B. In cats, Factor XII deficiency commonly recognized but rarely causes clinical bleeding.
• Extrinsic pathway – Starts w/ tissue injury, factor III (Thromboplastin) released. Factor VII.
• Common pathway – Factor V, X, prothrombin to thrombin, fibrinogen to fibrin.
• ATIII – Thrombin antagonist. Acts on II, IX, X, XI, XII.
• Vitamin K dependent factors - II, VII, IX, X. Vita K antagonism or deficiency assoc w/ rodenticide tox (warfarin, coumarin), malabsorption, BTO, heriditary (devon rex cats), and hemorrhagic porcine stress syndrome. Expect prolonged clotting times (PT, then PTT). PIVKA. If suspicious, tx w/ vita K and watch for improved clotting times w/in 24-48 hrs.
Vascular or platelet abnormalities Coagulation Factor Abnormalities
• hematomas rare
• multiple sites common
• mucosal bleeding common
• hemarthrosis rare
• prolonged bleeding from cuts
• purpura and ecchymoses common
• body cavity hemorrhage rare • petechiation rare
• hematomas common
• frequently localized
• mucosal bleeding can occur
• hemarthrosis common; delayed onset of bleeding, then profuse rebleeding
• purpura and ecchymoses rare
• big body cavity hemorrhage common
• Test of vasculature – Bleeding time test, biopsy.
• Test of platelets – Need good,clean stick. Platelet count, blood smear, platelet aggregation, bleeding time test.
• Test of coag factors – Intrinsic system w/ ACT, PTT (XII, XI, X, IX, VIII, II or I). Extrinsic system w/ PT (VII, X, V, II, I), also good test for vita K antagonism since factor VII has shortest t½ of vita K dependent factors.
• Fibrinogen and FDP assay for DIC, vWD assay in certain breeds (DPs), PIVKA (glorified PT, rodenticide testing).
• Inhibitors of coagulation – ATIII, aspirin, EDTA (binds divaalent Ca ions), heparing (activates ATIII), dicoumarol (vita K antagonist, rodenticide).
Coccidiomycosis - Coccidioides immitis. San Joaquin Valley Fever. Dimorphic soil pathogen. Fungus found in arid regions of SW USA. Infection via inhalation of fungal spores. Most common in dogs. Large (50+m) round organism w/ thick basophilic walls and small internal structures. Acute infections are respiratory in nature and usu self-limiting. Chronic respiratory disease affecting lungs, can disseminate to eye and bone. Osseus involvement has poor LT px, resembles osteosarcoma. Bone lesion of baboons.
• Clinical signs - Chronic cough, anorexic, cachexia, lameness, big joints, fever, intermittent diarrhea.
• Diagnosis - Dog w/ chronic bronchopulmonary diz in endemic area. Pulmonary nodules and enlgd hilar ln found on thor rads. Positive coccidiodin test indicates exposure. Serology helpful, do not culture.
• Treatment: Amphotericin B is drug of choice.
Coccidiosis - Causes acute invasion and destruction of intestinal mucosa. Problem in young animals, develop immunity as adults. Host-specific. Oocysts sporulate in environment w/in several days. Infection via ingestion of sporulated oocysts. Clean environment daily. Diarrhea may precede output of oocysts, so not always possible to dx coccidiosis via fecal exam. Impression smear of intestine more diagnostic. Finding oocysts in feces does not indicate coccidiosis infection unless clinical signs are present. Treat w/ sulfadimethoxine, a folate antagonist and coccidiostat and good sanitation.
• Poultry - Eimeria, Cryptosporidia
• Small animals - Isospora, Cryptosporidia
Coccidiosis (Bovine) – Cryptospordium & Eimeria zuernii, E. bovis, E. auburnensis. Occurs @ 1-2 mos to 1 yr. CS: diarrhea, soft foamy to watery, may contain mike, blood mucus & bile. Tenesmus, dehydration, Dx: fecal flot in Sheather’s Soln. Tx: Supportive. Coccidiostats. Control is important. “all in/all out”, etc.
Coccidiosis (Porcine) - piglets 5 - 15 days old. Causes acute invasion and destruction of intestinal mucosa. Problem in young animals, develop immunity as adults. Host-specific. Oocysts sporulate in environment w/in several days. Infection via ingestion of sporulated oocysts. Clean environment daily. Diarrhea may precede output of oocysts, so not always possible to dx coccidiosis via fecal exam. Impression smear of intestine more diagnostic. Finding oocysts in feces does not indicate coccidiosis infection unless clinical signs are present. Treat w/ sulfadimethoxine, a folate antagonist and coccidiostat and good sanitation.
Coccidiosis (Pet Birds) – much more common in gallinaceous or Columbiforme birds. Reported occasionally in psitticines & passerines.
Coccidiosis (Poultry) – Eimeria necatrix & E. tenella – Most Patho in Chickens.
Agent Infection site
E. tennela Cecum.
E. nacatrix ant. & mid S.I. but oocysts in ceca.
E. acervulina upper ½ S.I.
E. brunette lower S.I., rectum, ceca, cloaca
E. maxima S.I.
E. mitis lower S.I.
E. praecox upper S.I.
E. hagani anterior S.I.
E. mivati anterior S.I
Control : vacc & anticoccidial drugs.
Turkeys: E. adenoeides, E. dispersa, E. gallopavonis, E. meleagrimitis.
Ducks: Eimeria, Wenyonella, Tyzzeria spp
Geese: Eimeria truncate
Coccidiosis (Sheep & Goats) – Sheep: Eimeria ahsata, E. ovinoidalis (ninakohlyakimovae)-Lambs 1-6 mos @ greatest risk. CS: diarrhea ± blood or mucus, dehydration, fever, anorexia, weight loss, wool breaking, death. Ileum, cecum, & upper colon most involved. Dx: not based upon fecal oocysts alone! Diarr + oocyst count >20,000/g = coccidiosis. Tx: prophylactic coccidiostats.
Goats: E. arloigi, E. christenseni, E. ovinoidalis. Most patho to Kids. Dx: Diarr + oocyst count @ tens of thousands to millions per gram of feces = coccidiosis.
Control: sulfadimidine @ 55g/tonne.
Colibacillosis (Sheep & Goats) – Escherichia coli. Major cause of economic loss in newborn farm animals. Major cause of diarrhea. Cause septicemia, enterotoxemia. Risk factors: colostrums deprivation, inferior milk replacers, & overcrowding. CS: weakness, collapse, diarrh, dehydr. Dx; isolate & culture of org from feces. Tx: Abs, fluids & electrolytes.
Colic (Medical /Surgical) - SI of equine approx 80 feet. Bands on colon: cecum, RVC, LVC have 4 bands; LDC and pelvic flexure have 1 band; RDC has 3 bands. Gas/spasmodic colic or impaction colic. Never use Acepromazine in shocky horse, will collapse. Dx/Tx – HR/Resp, gut sounds, pass tube, mineral oil if not refluxing, rectal exam, belly tap, NSAIDs, walk. Refer if nonresponsive pain, reflux.
• Small intestine is either strangulating (SI torsion, SI volvulus, strangulating lipoma) or nonstrangulating (ileal impaction, proximal enteritis). Anterior enteritis DPJ – stinky, copius reflux, feels better when removed.
• Large colon is either colon torsion (nephrosplenic ligament = L dorsal displacement, or tangled w/ cecum = R) or impaction (transverse colon, pelvic flexure, ileocecal valve).
Enteroliths – Arabians, CA, alfalfa hay.
Sx: Exploratory Lapararomy. Ventral midline incision. Umbilicus to xyphoid.
• Open Abdo & note what you see.
• Preliminary exploration. Gently sweep w/ hand.
• Deeper exploration
• Find small intestine
• Find large intestine
• Pull out pelvic flexure
Be systematic and look for abnormalities.
Collapsing Trachea (Canine) – et. unknown. Most common in toy & miniature breeds. CS: nonproductive, honking & chronic cough. Frequently obese w/ concurrent cardoivascular/pulmonary dse (chronic bronchitis). Tx: weight loss, restrict exercise, reduce excitement/stress, Meds: antitussives, antibiotics, bronchodilators, corticosteroids.
Collie Eye Anomaly - Recessive inherited choroidal hypoplasia. Associated defects include scleral ectasia, coloboma of the optic disc, retinal folds and detachment, microphthalmia. Seen almost exclusively in collies and shetland sheepdogs.
Color Dilute Alopecia – Congenital defect in blue dobies, chows, chihuahuas. Clumped melanosomes in hairs. No cure, decrease risk of 2 bacterial infections.
Combined Immunodeficiency Syndrome - Inherited defect of immunity in Arab foals. Lack of immunoglobulin synthesis, absence of cell-mediated immunity, thymic hypoplasia, marked reduction of lymphocytes. Autosomal recessive.
• Clinical signs - Foal normal at birth dt maternal antibodies. As maternal antibodies decline, foal succumbs to succession of respiratory infections.
• Diagnosis - Precolostral serum samples have no detectable IgM antibody and lymphocyte count < 1000 cells/ml in peripheral blood.
Congenital Heart Abnormalities – listed in decr. prevalence
Dogs: PDA, Pulmonic Stenosis, Subaortic Stenosis, PRAA, Vent. Septal Defect, Tetr of Fallot, Atrial Septal Defect, Persist L Cran Vena Cava, Mitral Dysplasia, Tricusp Dysplasia, Cor Triatriatum Dexter.
Congenital Hyperlipidemia - Inherited disease of miniature schnauzers.
Congestive Heart Failure (Canine) - blood congests the veins and capillaries develop sufficient pressure to drive serum out of capillaries and into interstitial spaces faster than lymphatics can return it back to blood; this results in edema of the organ in which venous effluent is inadequate; get pulmonary edema when left ventricle fails (left-sided heart failure so see cough); ascites or pitting edema if right side fails (right sided heart failure so increased right atrial pressure so see back-up and jugular venous distension, subcutaneous edema and ascites).
1. sodium restricted diet
2. diuretic: loops (most common; such as furosemide which inhibits resorption of Na, K, Cl, H so excreted and water follows), thiazides, potassium-sparing; to reduce vasoconstriction.
3. Hydralazine (directly dilates arterioles)
4. Nitroglycerine (venodilator)
5. Sodium nitroprusside (vasodilator)
6. Positive inotropes (digoxin and digitoxin : increases intracellular calcium causing modest increase in contractility; but narrow TI) and (dobutamine: synthethic catecholamine that stimulates beta one adrenergic receptors so cardiac contractility increases).
Congestive Heart Failure (Equine) – RIGHT side CHF: fluid back out to periphery caudal & cranial vena cava. CS: edema, ascites, jugular pulsation. LEFT side CHF: fluid into Lungs. CS: dyspnea.
Constipation – 1) Protatomegaly in dogs, 2) pelvic fractures in cats (real concer if cat preg), 3) hypothroidism in dogs.
Contagious Ecthyma - aka Contagious Pustular Dermatitis, Sore Mouth, Orf. Poxvirus, related to pseudocowpox and bovine papular stomatitis. Infectious dermatitis of sheep and goats transmitted by direct contact, usually in young. Goats > sheep. Organism is highly resistant to dessication. Lesions on skin of lips with extension into oral mucosa, also on feet, interdigital regions. Vaccination. Once recovered usu highly resistant. ZOONOTIC, vets and sheep handlers lesions on hands, face usu more proliferative, distressing.
Contagious Ecthyma (Sheep & Goats) - aka Contagious Pustular Dermatitis, Sore Mouth, Orf. Poxvirus, related to pseudocowpox and bovine papular stomatitis. Infectious dermatitis of sheep and goats transmitted by direct contact, usually in young. Goats > sheep. Organism is highly resistant to dessication. Lesions on skin of lips with extension into oral mucosa, also on feet, interdigital regions. Vaccination. Once recovered usu highly resistant. ZOONOTIC, vets and sheep handlers lesions on hands, face usu more proliferative, distressing
Contagious Equine Metritis (CEM) - Taylorella equigenitalis. Highly contagious venereal disease of horses. REPORTABLE. Transmitted during coitus, resides in smegma of stallion prepuce. Self-limiting. CS: – None in male. Mare develops endometritis w/ vulvar discharge 2-6 days after service. Low conception rate. Once infection subsides, fertility is regained. Abortion uncommon. Dx: Recovery of organism. Hemagglutinating antibody. Tx: eradicated from USA but possible to import. Chlorhexidine & nitrofurozone cream. Uterine lavage. Px: isolate & test horses that have been off property. Strict hygiene during breeding.
Contagious Footrot (Sheep & Goats) – malignant footrot, virulent footrot. Et: mixed infxn of 2 G- anaerobic bact; Fusobacterium necrophorum + Dichelobactor nodosus. CS: interdigital stratum corneum is infected. Lameness, sheep recumbent on knees hairless & ulcerated. ↓BC. Epidermal necrosis & horny hoof may separate from foot. Dx: characteristic CS, Tx: foot soaking in 10% zinc sulphate etc, & penicillin + dihydrostrep.
Conjuctivitis – common in all species. Et: from infectious to irritants. CS; hyperemia, chemosis, ocular discharge, follicular hyperplasia, mild ocular discomfort. Specific Dx: depends on Hx, phys exam, conjuctival scrapings & culture, Schirmer tear test, biopsy. Unilateral conjuct: foreign body, dacryocystitis, keratoconjuctivitis sicca, Cats: FHV-1, Mycoplasma, P. psittaci. Bilateral conjunct: common in viral infxns in all spp. Herpesv in cattle, horses, pigs. If purulent bact. component. Environ irritants in all species. Tx: remove irritants, forn bodies, parasites. Correct conformational defects. Top tetracycl for Chlamydophila & Mycoplas. Antiviral meds for herpesv. Oral L-lysine for cats w/ FHV – 1.
Constipation – 1) Protatomegaly in dogs, 2) pelvic fractures in cats (real concer if cat preg), 3) hypothroidism in dogs.
Copper Deficiency - Common in Texas in young pastured ruminants. Cu stored in liver, absorbed in SI and excreted in bile. 1º dt decreased Cu in soil and forage, 2º dt interdependent - Mo Cu, Fe Cu, SMo.
• Clinical signs – Unthiftiness, achromotrichia, diarrhea, lameness, demyelinization, falling disease. Swayback in lambs, anemia.
• Diagnosis – Liver Cu [ ], serum Cu [ ], cerulopasmin in serum, diet Cu [ ].
• Treatment – Copper gylcinate injection every 6 mos SQ. Copper sulfate in feed. Copper oxide needle bolus.
• Prevent – Salt/trace mineral mixes with Cu. CuSO4 fertilizer.
Copper Poisoning – Sheep. Chronic ingestion of excess amount of Cu leads to sequestration in liver. A stressor induces sudden release of copper from the liver, resulting in severe intravascular hemolysis.
• Clinical findings - Acute hemolytic crisis, depression, weakness, anorexia, hemoglobinuria, jaundice.
• Control - Restrict copper intake; supplement with molybdenum.
Copper Storage Hepatopathy of Bedlington Terriers - Recessive inherited copper storage disease in which Bedlington terriers accumulate copper in liver. See signs of liver disease, slowly progressive hepatopathy, usu by 3 yrs old.. Incurable. Manage with penicillamine. Trientine. Severe disease. See similar diz in Westies, but mild.
Corkscrew Claw - Heritable defect of the lateral claw of cattle. Causes serious 2 lameness. Must trim continually. Cannot diagnose from dorsal aspect. Cull.
Corneal Ulcer – (K9, Fel) superficial: only the epithelium and possibly superficial stroma; deep: greater thickness of stroma involved.
Healing: epithelial: epithelial cells migrate over defect within a few hours, mitosis occurs within few days, completed in 5-7 days; stromal: slower, more complex with possible fibrovascular infiltration, may take several weeks.
Et: trauma, adnexal diseases (distichiasis, ectopic cilia, entropion, ectropion, trichiasis, eyelid mass), tear-film abnormality (quantitative deficiency such as KCS, qualitative tear deficiency such as conjunctival goblet cell deficiency, FHV -1, lagopthalmos (inability to close eyelids. eg from idiopathic facial nerve paralysis in cocker spaniels), innate corneal disease eg EBMD, foreign body, chemical burns, immune-mediated.
Dx: flourescein staining, cytology from corneal scraping.
Tx: STEROIDS CI! Restrict activity to not rupture eyeball, e-collar if self-traumatizing, topical antibiotics BID to TID (triple, chloramphenicol, oxytet/polymixin B [terramycin], gentamicin, tobramycin; if suspected melting (pseudomonas) use gentamicin and tobramycin)), atropine 1% ointment BID to TID (parasympatholytic so iris sphincter relaxes causing mydriasis for comfort, contraindicated if glaucoma), antiviral (for cats), acetylcysteine aka mucomyst (anticollagenolytic), nsaids (aspirin in dogs 10 mg/kg PO BID), patients own plasma collected in EDTA (anticollagenolytic, keep in fridge, discard after 48 hours).
Coronavirus (Canine) – Milder than parvo but cannot distinguish by clinical signs. Diarrhea, vomiting.
Coronavirus (Bovine) – transmit fecal/oral route & air. Alltacks sm & lrg intestines. More virulent than rotavirus. CS: malobsorptive/maldigestive diarrhea ±mucus. ± pneumonia. Dx: difficult. FA, ELISA. Electron mmicroscope. Tx: supportive. Hygiene key for control.
Corticosteroid Responsive Meningitis - Large breed, < 2 y.o., cervical pain, rare to have neuro disorder, px excellent with treatment.
Corynebacterium infection (Bovine) – Cutaneous abscesses and mastitis. Abscesses: Actinomyces (Corynebact) pseudotuberculosis. Problem late summer to winter. CS: ventral lymphadenitis, large ulcers on skin (8 in diam), spongy necrotic debris, ulcerative dermatitis. Dx: based on Hx, CS, isolation of corynebact. Tx: often spontan healing. Topical. Mastitis: Corynebactium bovis. Rare. Colonizes teat canal. Indicates ineffective teat dipping. Routine dipping prevents infection.
• Horse – Causes pectoral abscesses. Seasonal, late summer and fall. Transmitted by fomites, arthropods, skin wound. Lance abscesses, flush with iodine. Penicillin or TMS may be used, but antibiotic therapy may delay abscess maturation.
• Sheep/Goats - see Caseous Lymphadenitis in sheep and goats.
Cough (Canine) – CS in respiratory dse.
Et: Nasal cavity and sinuses dZ w/ postnasal drip
Pharyngeal & Laryngeal disorders:
Infections (bact, viral, fungal, paras)
Everting laryngeal saccules
Tracheal & lower airway disorders
Viral (distemper, parainfluenze [dogs] herpes & calici [cats])
Bacterial (Bordatella bronchisepticum)
Parasitic (Filaroides, Capillaria sp.)
Anomalies (collapse, hypoplasia, 1o cilliary dyskinesia,
Pulmonary parenchymal dse
Allergy (pulmonary infiltrates w/ eosinophillia),
Fungal (Blastomyces, Crytococcus, Aspergillus)
Protozoal (Toxoplasmosis, Pneumocystis)
Parasitic (Filaroides, Dirofilaria, Paragonimus)
Neoplasia (1o or 2o)
Left atrial enlargement (Causing bronchial compression
Mediastinal Dse (causing airway compression)
Lymphosarcoma (esp cats)
• CN I - Olfactory nerve. Sense of smell.
• CN II - Optic nerve. Vision. Prechiasmal vs postchiasmal (PLR intact, no menace).
• CN III - Oculomotor nerve. Motor to muscles of eye, constriction of pupil, accommodation. Divide into 3 major branches: Ophthalmic n. (sensory to eyeball, medial canthus, nasal mucosa), Maxillary n. (sensory to dorsal/rostral head), Mandibular n.(motor to mastication mm. and sensory to lower jaw).
• CN IV - Trochlear nerve. Motor to dorsal oblique muscle of the eye.
• CN V - Trigeminal nerve. Motor to muscles of mastication and sensory to head.
• CN VI - Abducens nerve. Motor to lateral rectus and retractor bulbi. Abduction of eyeball.
• CN VII - Facial nerve. Motor to muscles of facial expression and sensory to rostral tongue/taste.
• CN VIII - Vestibulocochlear nerve. Sense of hearing and proprioception.
• CN IX - Glossopharyngeal nerve. Motor and sensory to pharynx and caudal tongue. Gag reflex, taste on caudal 1/3 of tongue, involuntary phase of swallowing.
• CN X - Vagus nerve. Parasympathetic to viscera of neck, thorax, abdomen. Motor to skeletal mm of pharynx, laryns, esophagus and sensory to mucosa. Gag reflex, coughing, swallowing.
• CN XI - Accessory nerve. Motor to skeletal mm of neck and trapezius.
• CN XII - Hypoglossal nerve. Motor to intrinsic and extrinsic ms of tongue.
• Remember CN w/ parasympathetic functions: CN III, VII, IX, X, XI.
• OOOTTAFVGVAH; SSMMBMBSBBMM.
Crotalaria - Group of plants that contain pyrrolizidine alkaloids. Liver damage in horses.
Cruciate Ligament - Cranial cruciate ligament rupture most common, medial meniscal tear accompanies w/ clicking noise. Dx via cranial drawer motion in acute cases, capsular thickening in chronic cases. Rad signs include loss of infrapatellar fat pad, joint mice, reactive new bone at tendon insertions (caudal femur, cranial tibial plateau).Multiple techniques to repair. Conservative therapy works in small animals. Surgical repair necessary in larger animals (>15kg). CCLR in bovine, cannot kick. In dairy, usu dt trauma. In bulls, dt conformation. Salvage.
Cryptococcosis – Cryptococcus neoformans. Encapsulated fungal organism found in soil, pigeon droppings. Yeast w/ narrow based budding and thick, clear mucin capsule. Infection via inhalation of spores - cats > dogs.
• Clinical features – Nose and brain. Cats: Roman nose. Swelling or draining fistula over facial bone, chronic nasal discharge. Dogs: CNS signs, granulomatous chorioretinitis.
• Diagnosis - Latex agglutination test detects circulating antigen. One of few sensitive, specific serologic tests for fungal infection. Cytologic dx relatively easy as can ID capsule. CSF fluid, India ink – clear vacuoles.
• Treatment - Several protocols, Amphotericin B, ketoconazole, fluconazole if in CNS.
Cryptorchidism – common in stallions, boars, & the most common develop. disorder in dogs. 2:1 R:L ratio. Seq. to Sertoli cell tumor. CS: empty scrotum at 6 months. Undescended testicle located in abdomen, inguinal canal or lat to penis. Dx: palpate. Tx: castration. Don’t Breed.
Cryptosporidiosis (Bovine) – see Coccidiosis. Flat calf syndrome. ZOONOTIC, kills immunosuppressed (AIDS).
Curb – Spraining and thickening of the plantar tarsal ligament.
Cushings – Hyperadrenocorticism. Elevated cortisol 2 to excessive pituitary excretion of ACTH, excess cortisol production by the adrenal gland, or excess exogenous cortisol. Most common in dogs is pituitary tumor.
• Clinical findings – PU/PD, bilaterally symmetrical alopecia, pendulous abdomen. PP, panting, weakness, muscle wasting, calcinosis cutis. Eosinopenia, neutrophilia, hepatomegaly, SAP.
• Diagnosis - ACTH stimulation test (can determine if iatrogenic). Low-dose dex suppression test. High-dose dex suppression test. Will not depress adrenal tumors. Abdominal ultrasound to visualize adrenal tumors. Urine cortisol:urine creatinine test, if may have it, further testing reqd.
• Treatment - opDDD (Mitotane). Removal of adrenal tumor. Ketaconazole (impairs steroid synthesis), deprenyl.
• Feline Cushings – Diabetes and thin skin. Dx w/ HDD. Difficult to dx, no good tx.
Cutaneous Asthenia – Ehlers-Danlos syndrome. Inherited defects in collagen production. Dermatosparaxis = torn skin; stretchy, loose, fragile skin, impaired wound healing. In cats, ddx acquired skin fragility and hyperadrenocorticism. Often unsuitable as pets.
Cutaneous habronemiasis (Equine) – aka Summer Sores. Habronema - Stomach worm of horses. H. muscae, H. microstoma, and Draschia megastroma. Causes catarrhal gastritis. Cutaneous. The stomach worm larvae emerge from flies feeding on genitalia, eye or wound. Invade skin and irritate tissue, which causes a chronic granulomatous reaction. Tx: insect repellents, topical organophosphates (to kill larvae). Surgical removal of excessive granulation tissue.
Cutaneous Tumors (Equine) – most common neoplastic disorder in domestic animals. Classification is difficult and controversial because cutaneous tumors are so diverse.
• basal cell tumors/basal cell carcinomas
• intracutaneous cornifying epitheliomas
• squamous cell carcinomas
Cuterebra spp. – (Fel & K9 & Rabbits) large, bee-like flies. Female flies lay eggs along rabbit runs & near rodent burrows. L1 hatch and attach to fur as host brushes past.
Deposited eggs hatch, allowing larvae to enter nares/mouth/ open wounds. Larva migrate to host’s SubQ tissues and communicate w/ air through breathing hole. Exit after 30 days to pupate. Tx: Ivermectin.
Cyanide Poisoning - Inhibits cytochrome oxidase and causes death from anoxia. Cherry red blood. Dyspnea, tachycardia, salivation, vomiting, asphyxial convulsions. Bitter almond odor. Treat w/ sodium nitrate, sodium thiosulfate. Sorghums.
Cyclophosphamide – Antineoplastic, immunosuppressive. Alkylating agent. Interferes w/ DNA replication, RNA transcription and replication. Disrupts nucleic acid fxn. Adverse effects include myelosuppression, gastroenterocolitis. Hemorrhagic cystitis rare in cats; 1/3 of dogs receiving > 2 mos develop hemorrhagic cystitis.
Cyclosporine – Immunosuppressive. Suppresses T lymphocytes; used in organ transplant recipients.
Cystic Follicular Degeneration (Bovine) – dt ovulation failure. Jerseys & Guernseys predisposed. Rare in Beef. CS: anestrus , Nymphomania, “Buller” cows. Dx; based on Hx, CS, Rectal- Cysts and flaccid uterus. Lab- ↓ plasma progesterone. ↑ milk progest. Tx: Luteinze – hCG, GnRh, PgF2ά.
Cystitis – (K9, Fel) Et: e-coli, Staph aureus, Proteus, Klebsiella, Strep.
Dx: cysto UA and culture; see increased hemoglobin and protein; rbcs, wbcs, bacteria, pH alkaline; double contrast cystourethrourography;
Tx: 2-3 weeks of ABs based on CS; ampicillin or TMS; do culture 5 days after stop abs ( if -, stop ABs; if +, continue on abs until 2 or more negative cultures.)
Cytauxzoon felis – Natural parasites of wild felids. Transmitted by Dermacentor variabilis tick. Multiply in macrophages (unlike Theileria which multiply in lymphocytes). When transmitted via tick to domestic cats, causes acute and usu fatal diz. Transmission via blood infection usual variable and often not fatal.
• Clinical signs – Onset ~10d, with severe signs w/in the next week. Febrile, dyspneic, dehydrated. Icteric and anemic. At necropsy, spleno/hepatomegaly, enlgd ln, edematous kidneys. Edema, congestion, and petechia of lungs.
• Diagnosis – Normocytic, normochromic anemia w/ leukopenia and pronounced lymphopenia. Occasionally can dx via blood smear, see macrophages w/ schizonts in cytoplasm.
• Treatment – Little success. Tick avoidance.
Dacryocystitis - Inflammation of lacrimal sac. Obstuction of proximal nasolacrimal duct by inflammatory debris, FBs or masses. Produces epiphora and 2 conjunctivitis refractory to treatment.
Daily Water Requirements - 50-75 mL/kg/day.
Declaw – Onychectomy. Surgical removal of the third phalanges and claws. Need to remove entire ungual crest or claw will grow back.
Decubitus ulcers: Pressure wounds due to immobility / paralysis. Tx- treat the ulcers by debridement. Provide soft padding and change position frequently.
Dehorning - Cattle chemical/caustic (newborn calves), electric dehorning (upto 4 wks), hot iron method (upto 12 wks), Gouge or barnes type ( upto 4 inches long horn can be removed)
Goats Should be done day 1-2. Hot iron debudding method of choice (careful not to burn brain). Use restraint box and nerve block or general anesthesia.
Degenerative joint disease : progressive degeneration of articular cartilage – hyaline cartilage thinning, joint effusion and periarticular osteophyte formation. Caused by trauma, infection, immune mediated dz or developmental problems. CS: pain and lameness secondary to joint dysfunction or muscle atrophy. Joint swelling, osteophytosis, subchondral bone sclerosis and narrowed joint space. TX – surgery (joint fusion, femoral head osteotomy, joint replacement, amputation ) or medical (wt reduction, controlled exercise, NSAIDS, warm compress, etc.)
Demodectic Mange –
• Dog – Face, lips, eyes, legs, feet. Folliculitis w/ alopecia, pustule formation. Nonpruritic. Generalized demodecosis indicates immunosuppression. Normal flora of dogs passed from bitch to pups w/in 1st few days. Dx by deep skin scraping. Tx w/ Amitraz (Mitoban - MAO inhibitor, yohimbine will reverse) once a week until two (-) skin scrapings. Amitraz is only licensed drug for tx. Also ivermectin, milbemycin given daily. Steroids contraindicated.
• Cat – Stumpy demodex, Demodex gatoi. Pruritic, contagious. Broad superficial scraping as lives in surface. Do NOT use Mitoban, will kill cats. Lyme sulfur dips once a week for 6 weeks (do not allow licking of wet dip).
Dentistry – See dental formulas in Merck, p. 131-132. In aging animal see narrow pulp cavity, thick dentin, and loss of definition of lamina dura. Scale below gum line q/ currette (subgingival). Scale above gum line w/ scaler (supragingival).
• Large animal – Horse most commonly, sharp points develop (buccal uppers, lingual lowers), see quidding, slow eating, reluctance to drink cold water; wave mouth, step mouth. Enamel points should be treated by regular dental prophylaxis (floating). Removal of deciduous canine teeth in piglets, tusk amputation in boars.
• Small animal – Periodontal disease is bacterial infection of tissue surrounding the teeth. Gingivitis is inflammation of marginal gingival tissues induced by bacterial plaque (peridontal ligament or alveolar bone not affected). Reversible w/ teeth cleaning below gingival margin, but may progress to periodontitis. Periodontitis is destructive inflammatory process driven by plaque that destroys gingiva, periodontal ligament, alveolar bone and root cementum. Tx w/ cleaning below and above gum line.
• Gingival Hyperplasia – Benign overgrowth of gums, predisposition in brachycephalic breeds (familial gingival hypertrophy). Usu asymptomatic, if problematic, gingivectomy.
• Neck Lesions – In cats, destructive diz of tooth crown and roots. Rads to see if treatable.
• Feline Stomatitis Complex – Intense reaction to diz, severe inflammation of oral cavity. Tx w/ aggressive dental or may require full mouth extractions.
• Fractured, discolored teeth – when a tooth fractures, pulp chamber gets infected, followed by infection of tooth apex, surrounding bones, and finally systemic infection. Root canal or extraction can be done.
• Root caries – can occur secondary to periodontal dz or trauma. External resorption of tooth structure.
• Enamel hypoplasia and dysplasia – fever and deposition of chemicals within the tooth, and severe malnutrition during development of enamel may cause permanent damage – eg: fever caused by canine distemper virus. Use composite bonding and frequent dental prophylaxis.
Dermacentor variabilus – American dog tick. Transmits RMSF, tularemia, anaplasmosis (mice).
Dermatitis : superficial skin inflammation. May be caused by bacteria, viruses, or allergies/sensitivities to certain substances including insect venom. The primary types of dermatitis are perivascular dermatitis (acral lick dermatitis, flea bite hypersensitivity, sarcoptic mange, atopic dermatitis and other hypersensitivity to insect bites), irritant contact dermatitis, and Pemphigus foliaceus. Urtcaria, papules, scales and crusts, lack of lustre of skin coat, etc. are also indicative of dermatitis.. Tx: Lifestyle modifications, avoid exposure to allergens and insects, cortisone treatment in some case
Dermatomyositis - Inherited diz of collies, shelties, corgi. Etiology unknown, likely autosomal dominant. Skin lesions and rare myositis. Dx by biopsy and clinical sx. Tx controversial.
Dermatophilosis - Dermatophilus congolensis. Wide host range. G+ bacterial infection of the epidermis, susceptible to a wide range of antibiotics. Grows under wet conditions. Raised tufts of hair, crusty lesions which pull off to reveal moist, red lesion underneath. Dorsum, muzzle, and distal limbs. Organism remains quiescent in skin until rainy season ( high humidity/ temperature). Occasional death. Most economic loss is due to damaged hides. Dx via cytology, gram stain. To tx, wear gloves, remove and destroy crusts, povidone iodine shampoo. Spontaneous recovery after 3 wks or during dry weather. ZOONOTIC.
Dermatophytosis – Ringworm. Transmission via contact with infected individuals, fomites. Most susceptible are young, debilitated or immunocompromised. Face, feet, or anywhere. Epidermal collarettes, scale, alopecia. Infect only growing hairs. Cats are often a reservoir.
• Diagnosis -Wood's lamp will fluoresce with M. canis 50% of the time. DTM – growth apparent 3-7 days, maybe 3 wks. Dermatophytes produce color change to red when colony 1st visible (saprophytes will eventually cause color change, need to look at DTM cultures daily). KOH staining for direct identification.
o Cattle/sheep/goats - Trichophyton verrucosum.
o Horse - Trichophyton equinum. Saddle, tack, pastern. Submit fungal culture to lab (B complex, hard to grow). More common in winter with stabled animals.
o Pig - Microsporum nanum.
o Dog - > 70% caused by Microsporum canis - alopecic scaly patches with broken hairs. M. gypsum lives in soil. Trichophyton mentagrophytes is harbored in rodents, nasty, inflammatory disease seen in immunosuppressed.
o Cat - > 98% caused by M. canis, focal alopecia, scaling, crusting around ears, face, extremities. Cats harbor M. Canis, look for source. Can dx via toothbrush technique, place onto auger for fungal growth.
• Treatment – Usually self-limiting, but ZOONOTIC. Griseofulvin (teratogenic, admin only if > 12 wks, add fat for absorption, do NOT used in FIV+ cats, idiosyncratic BM aplasia in cats) and lime sulfur. Oral lufenuron (Program). Can consider topicals – miconazole, clotrimazole, nystatin, thiabendazole. Lime sulfur. Steroids contraindicated.
Developmental bone disorders
Hip dysplasia – heritable, affected by nutrition.. 3- 8 months of age.- joint laxity and subsequent degenerative joint disease (acetabular bone sclerosis, osteophytosis, thickened femoral neck, joint capsule fibrosis, and subluxation or luxation of femoral head). Disparity between hip joint muscle mass and rapid bone development results in hip dysplasia. CS – variable degree of lameness increasing after exercise, joint laxity, reduced range of motion and crepitation and pain during full extension and flexion. DX- x-rays . TX- medical (weight management, exercise restriction, physical therapy) or surgical ( Femoral head osteotomy, Triple pelvic osteotomy, pectineal myotenectomy, total hip replacement, etc.)
Osteochondrosis- Disorder of medium and large rapidly growing dogs of the articular-epiphyseal cartilage complex and the growth plate. There are site predilections for the humeral head, the femoral condyles of the stifle, femoral trochlea, medial ridge of the talus, and medial condyle of the humerus. CS- lameness, joint effusion, reduced range of motion in affected joints. . Dx- radiography - changes include flattening of joint surfaces, subchondral bone lucency or sclerosis, osteophytosis, joint effusion and joint mice. Tx- sx and NSAIDs.
Elbow dysplasia Either Fragmented medial coronoid process, ununited anconeal process, or osteochondrosis of humeral condyle. CS: Affected animals are lame and have swollen painful elbow joints and muscle atrophy. In chronic cases joint crepitation and reduced range of motion. Tx – sx before DJD develops and NSAIDs
Osteochondrosis (Osteochondritis dissecans, Dyschondroplasia): most important – affects articular cartilage -arise from a focal disturbance in endochondral ossification caused by rapid growth, overnutrition, mineral imbalance, and biomechanics (ie, trauma to cartilage) or genetics (standardbred and swedish warmblood). Genetics has been implicated in some breeds (eg, Standardbred and Swedish Warmblood). CS: a nonpainful distention of an affected joint (eg, gonitis, bog spavin). In foals, a tendency to spend more time lying down, joint swelling, stiffness, upright conformationf limbs, etc. Fetlock osteochondrosis is seen in younger foals (<6 mo old). Dx –xray Tx: Mild cases recover spontaneously, restrict exercise.Lesions in shoulder have a guarded prognosis.
Physitis (Epiphysitis, Physeal dysplasia, Dysplasia of the growth plate): swelling around the growth plates of certain long bones in young horses. It can be a component of osteochondrosis. Caused by malnutrition, conformational defects, faulty hoof growth, compression of the growth plate, and toxicosis. Most commonly involves the distal extremities of the radius, tibia, third metacarpal or metatarsal bone, and the proximal aspect of the first phalanx. Dx: X-rays Tx: reducing food intake, restricted exercise, Ca:P ratio 1.6:1
Flexion deformities (Contracted tendons, Club foot, Knuckling): are associated with postural and foot changes, lameness, and debility. Fetal malposition, teratogenic insults, and genetic defects have in newborn foals, or chronic pain (from physitis, osteochondrosis, DJD, wounds, etc.), later on. Tx: Desmotomy, Splints and casts, forced extension. In sucklings and weanlings nutritional correction, hoof trimming and analgesia.
Diabetes Mellitus – Dog, insulin dependent. Cat, insulin dependent or non-insulin dependent (achieve remission with high fiber, high protein diet, weight loss, or oral hypoglycemics). Treat diabetic ketoacidosis with regular insulin. Insulin antagonists include cortisol, growth hormone, epinephrine, and glucagon
Type I: Insulin dependent DM (IDDM):beta cells are destroyed (or absent)- decreased insulin production and secretion. Leads to ketoacidosis since fatty acids are burned for fuel.
Type II: Non Insulin dependent DM (NIDM): peripheral resistance to insulin. Less severe then type I and can be controlled by dietary management. It may be caused by down-regulation of insulin receptors (obese animals), insulin receptor antagonism (excessive growth hormone due to diestrus and elevated progesterone levels in intact females, or excess cortisol levels (Cushing’s disease), or excess epinephrine, glucagon or excess or deficiency in thyroid hormone.
CS: polyuria, polydipsia, polyphagia, UTI and other infections, cataracts. Signs of ketoacidosis – vomiting, diarrhea, anorexia, dehydration, stupor or coma and acetone breath.
- ALT and ALP may be elevated,due to secondary hepatic lipidosis
- hypercholesterolemia (>300mg/dL) due to lipolysis and change in lipoprotein metabolism
- Other secondary changes may include BUN and creatinine, low bicarbonate (in ketoacidic animals), hyperosmolality (in ketoacidotic animals), decreased ions (Na, Cl, K) due to PU/PD and hyperglycemia, elevated lipase (pancreatitis)
- specific gravity >1.015 (helps differentiate pre-renal azotemia from primary renal failure)
- Proteinuria (associated with UTI)
Tx: maintain BG between 80 -200 (before cataract development) or 80-300 mg/dL (after cataract development). Dietary management (high fibre, weight reduction, feeding low fat highly digestible food in case of pancreatitis). Oral hypoglycemic agents in NIDM animals. Sulfonylurea drugs such as glipizide (stimulates insulin secretion, enhance sensitivity to insulin, decrease glycogenolysis, increase hepatic glucose utilization and decrease hepatic insulin extraction.)
Insulin: the shorter-acting the drug the more potent it is. Zinc and protamine can slow down the sq absorption and prolong the effect of the insulin. Regular insulin is quick acting but short lasting (used in emergencies, can be given IV, IM and SQ), NPH and lente are intermediate-acting insulin that take action in 0-3hrs and lalst 4 –10hrs. and Ultralente is long-acting.
Starting a dog on insulin: normally beef/prok lente insulin is used. Start by giving 1unit/kg in sml dogs and 0.5unit/kg in large dogs every 24 hrs. Glucose curve is recommended only after 4th day of therapy. It is recommended to repeat the glucose curve every 2 –4 months, or after changing the insulin dose, or when the urine contains ketone bodies or if the animal develops clinical signs.
Idiopathic large bowel diarrhea (colitis) Large bowel diarrhea characterized by increased frequency of small amounts of stool, with mucus, blood, and straining usually present. No apparent cause in most cases. Treated by dietary management
Clostridium perfringens diarrhea: Clostridium Perfringens has been associated with enteritis in dogs and cats. The diagnosis is made by 1. Signs of enteritis often with fever, blood and mucus in stool, presence of C. perfringens spores, 3. Presence of C. perfringens enterotoxin
Campylobacter associated diarrhea: Campylobacter spp., including C. Jejuni have been isolated from dogs with a parvovirus-like illness, and from dogs with chronic diarrhea. There may be a leukocytosis with a left shift. This agent may also be isolated from dogs without diarrhea, so the diagnosis rests on finding the bacteria and ruling out other causes of diarrhea
Coronavirus diarrhea: Corona viruses have been associated with diarrhea, particularly in young dogs, but can also be shed by healthy animals. Mixed infections with other agents can be associated with more severe signs. Infection is common, but serious clinical disease is not.
Dilated Cardiomyopathy – DCM. Most common in large breed dogs, esp DPs. Usu present for exercise intolerance and cough. Arrythmias commonly associated with DCM include atrial fibrillation and VPCs. Mainstays of tx are diuretics (if congested) and ACE inhibitors. Digoxin and vasodilators also. In feline, usu dt taurine deficiency (rare). Treat with taurine supplementation and resolves.
Diaphragmatic Flutter – aka Synchronous Diaphragmatic Flutter, "Thumps". Horse. Violent, unilateral hiccoughs occur w/ each heartbeat dt stimulation of the phrenic nerve by cardiac electrical discharge. Often related to athletic stress resulting in metabolic alkalosis, hypocalcemia, and electrolyte imbalance. Treat with calcium.
Diaphragmatic Hernia - Congenital or acquired (blunt trauma to abdomen and caudal chest). Abdominal viscera contained w/in thorax. Dx via rads, contrast rads or U/S. Surgical correction.
Dictyocaulus arnfieldi – Equine lungworms. Donkey, mules and asses are inapparent carriers. Chronic cough, expiratory effort, crackles/wheezes. Dx w/ Baermann float, hx, TTA. Tx w/ ivermectin. Do not graze horses w/ donkeys.
Digoxin – Toxicity is common. Hypokalemia increases toxicity dt binding of digoxin to myocytes. Cleared by kidneys, therefore renal disease also increases toxicity.
Digital Dermatitis – Hairy Heel Warts. #1 foot disease of dairy cattle. Most painful foot lesion seen- causes lameness unlike interdigital dermatitis. Anaerobic spirochete (Treponema) identified by Warthin-starry stain. Highly contagious(90% morbidity), difficult to eradicate. 90-95% in rear. Pain is diagnostic.Two types of lesions -erosive/reactive or proliferative. Treat herd with topical oxytetracycline foot bath long term. Topical paint of formaldehyde with waterproof bandage.
Dipylidium caninum – Dogs, cats acquire from fleas. Tx w/ Praziquantel (Droncit) or Fenbendazole (Panacur). See tapeworms.
Discospondylitis – Infectious diz of nervous/ms systems. Staphylococcus intermedius/aureus. Also dt Brucella canis (always check for), aspergillosus. Hematogenous or directly via grass awn (CA). Caudal cervical, midthoracic, L7-S1. Large breed, male, intact, middle aged dogs. Dx via rads, see lysis of end plates; culture of urine, blood; brucella titer. Tx cephalosporin (-lactamase resistant Ab). If Brucella, treat with tetracycline, minocycline.
Diseases of pads
Pododermatitis with crusted /hyperkeratotic foot pads no pruritus, multiple feet involvement,
In mature dogs, maybe immune mediated (pemphigus foliaceous, lupus, drug eruption), infections (rare), metabolic (hepatocutaneous syndrome –rare). In young dogs, caused by zinc deficiency or generic dog food syndrome, or lethal acrodermatitis in bull terrier pups ( zinc and infection related genetic disease)
Pododermatitis characterised by Ulcerated Foot Pads : causes – traumatic, infection, immunemediated, neoplastic (epitheliotrophic lymphoma) or allergic.
Pododermatitis characterised by swollen painful interdigital skin These are often more painful than itchy with lameness and careful licking. There is scale and crust with nodules, sinuses and exudation. Common causes are Demodex and/or furunculosis with Staph or Pseudomonas.
Diseases of the pharynx, larynx, and trachea
Pharyngitis: inflammation of the walls of the pharynx seen along with upper airway infections. Animals have difficulty swallowing, resulting in peripharyngeal cellulitis and abscessation Tx: Identify and eliminate primary causes.
Pharyngeal Lymphoid Hyperplasia: young horses (1-3 yr). Horses have many small foci or follicles of lymphoid tissue spread diffusely over the roof and lateral walls of the pharynx instead of distinct masses of tonsillar tissue like other animals. Occasionally these coalesce and become inflamed. Affected horses frequently have reduced appetites and appear lethargic.
Tx: Antibiotics, NSAIDs, rest
Laryngitis, an inflammation of the mucosa or cartilages of the larynx, may result from upper respiratory tract infection or by direct irritation from inhalation of dust, smoke, or irritating gas; foreign bodies; or the trauma of intubation, excess vocalization, or in livestock, by injury from roping or restraint devices. Laryngitis may accompany infectious bronchitis in horses. Edema is seen.
Laryngeal chondropathy is a suppurative condition of the cartilage matrix that principally affects the arytenoid cartilages; it is believed to result from microbial infection. Initially, there is often acute laryngeal inflammation. Later, there is progressive enlargement of the cartilages that commonly results in a fixed upper airway obstruction with stertorous breathing and reduced exercise tolerance.
CS: Harsh dry cough initially and soft, moist painful later on. Cough can be induced by pressure on the larynx, exposure to cold or dusty air, swallowing coarse food or cold water, and attempts to administer medicines.
Dx: clinical signs, laryngoscopy. Tx: Tracheotomy tube, NSAIDs and corticosteroids, systemic antibiotics, diuretic drugs, tx of primary disease, avoidance of causes.
Laryngeal hemiplegia Look under L.
Tracheal collapse: seen in toy and miniature breeds of dogs. Nonproductive, honking chronic cough, and dyspnea.
Laryngeal paralysis middle aged to older, large breeds of dogs – dry cough, voice changes, noisy breathing, stridor and collapse. Dx- laryngoscopy. Tx- surgical
Disruption of suspensory ligament (equine)
Proximal Suspensory Desmitis: proximal one-third of the metacarpus (or metatarsus). Relatively common and affects both forelimbs and hindlimbs, unilaterally or bilaterally (less common) of horses of all ages. lameness or poor performance. sometimes occurs in association with more distal limb pain (eg, navicular disease),poor mediolateral or dorsopalmar foot balance, straight hock conformation or hyperextension of the metatarsophalangeal joints. Dx: local anesthesia and ultrasound examination (diffuse or central hyopechoic areas with hyperechogenic foci in chronic cases). Tx is by stall rest, followed by a graduated program of exercise combined with correction of foot imbalance.
Desmitis of the Body of the Suspensory Ligament: This is principally an injury of forelimbs of racehorses and both fore and hindlimbs of standardbreds. CS: - vary - enlargement of the ligament, local heat, swelling, and pain. DX: clinical signs, ultrasound. Tx NSAIDs, hydrotherapy, controlled exercise.
Desmitis of the Medial or Lateral Branch of the Suspensory Ligament: Both hindlimbs and forelimbs, seen in all types of horses. Foot imbalance is a predisposing factor. CS: depend on the degree of damage and the chronicity of the lesion(s) and include pain on flexion of fetlock, localized heat and swelling, and variable degree of lameness. Prognosis is guarded. The condition may recur.
Disseminated Intravascular Coagulation (DIC) : Secondary to other diseases. In acute cases, uncontrolled hemorrhaging with inability to form a clot. All coagulation screening tests are prolonged. Death is caused by extensive microthrombosis or circulatory failure. If animal survives acute state, chronic form can ensue. Treatment should be directed at underlying problem. Supportive care, electrolytes etc. are recommended.
Distemper – Paramyxovirus. Initial respiratory signs, GI and CNS (chewing gum fits) signs may follow. Hyperkeratosis of the footpads and nasal planum. Suspect in any febrile condition in puppies. Febrile catarrhal illness with neurologic sequelae justifies dx of distemper. IFA of epithelium, buffy coat, necropsy. Demonstration of virus-specific IgM. Ferrets can contract diz, show rash on chin and inguinal area, anorexia, photophobia.
• Aldosterone antagonists – Late distal tubules. Weak. Spironolactone (also K+ sparing).
• Carbonic anhydrase inhibitor – Proximal tubules. Weak. Acetazolamide, used more often to IOP as tx in glaucoma.
• *High ceiling diuretics – Ascending loop of henle. Potent. Furosemide (K+ wasting). Most common.
• Osmotics – Proximal tubules. Moderate potency. Mannitol, often used for renal failure prophy, IOP, ICP (contraindicated w/ intracranial hemorrhage), mobilization of cellular edema.
• K+ sparing – Weak. Triamterene.
• Simple – Ethyl alcohol.
• Thiazides – Distal tubules. Moderate potency. Benzathiazide (K+ wasting), often used in edema mgmt.
Dorsal Displacement of the Soft Palate – In equine, exercise intolerance dt compromised airway. Gurgling, dyspnea, noise, “swallows tongue”, cough. Race horse that quits running suddenly. Dx via endoscopy (treadmill), rads. Treatment one of more of the following: 1) Sternothyrohyoid myectomy = strap mm. resection. 2) Staphylectomy = trim caudal edge of soft palate. 3) Epiglottic augmentation w/ teflon. 4) Lou Ellen’s tendenectomy. Ddx from entrapped epiglottis. Cannot see outline of epiglottis w/ DDSP.
Dourine - African venereal disease of horses caused by Trypanosoma equiperdum.
Downer Cow – 2 to inciting cause ( hypocalcemia, metritis, exhaustion due to calving, calving paralysis, toxic mastitis, hypophosphatemia, hypokalemia, hypomagnesemia and trauma). Beef, pregnant in winter, starvation, malnutrition- calving paralysis due to damage of obturator nerve or lumbar root of sciatic nerve.
Cycle of ischemia, hypoxemia, edema. BAR, drink and eat, but can’t rise. CK in short term, AST long term; not prognostic. Tx is supportive care, soft bedding, turn, flotation. Dairy, usu Milk Fever. Controlled dietary ca and P and dry matter intake during dry period.
Doxorubicin (Adriamycin) – Antineoplastic agent. Causes inhibition of DNA synthesis, DNA-dependent RNA synthesis and protein synthesis. Acute toxicity assoc w/ cardiac arrhythmias and mast cell degranulation (independent of IgE). Cumulative toxicity assoc w/ diffuse cardiomyopathy.
Duodenitis/ proximal jejunitis: Affects proximal portion of the small intestine and has various names including proximal enteritis-jejunitis, anterior enteritis, duodenitis-jejunitis. Cause is unknown.
CS: Varying degrees of abdominal pain, voluminous amounts of gastric reflux, progression from pain to depression, and moderate to severe distention of the small intestine on rectal examination. The distended duodenum may be palpated in many cases as it courses around the base of the cecum. The peritoneal fluid often contains an increased concentration of protein (>3 g/dL) with a normal number of WBC. Tx: Medical or surgical. Medical treatment includes continued gastric decompression until the gastric reflux abates, IV fluids, and analgesics, as required. Acute laminitis is a common complication.
Drug toxicities (equine)
Phenylbutazone – GI and oral ulcers, renal damage, blood disorders, protein loss.
Chlorpromazine – violent reaction alternates with periods of sedation.
Corticosteroids – laminitis
Reserpine (tranquillizer) – GI upset, colic
Ketoprofen _GI, oral ulcers, renal damage, blood disorders (less problems than phenylbutazone and flunixin)
Flunixin meglumine – same as phenyl butazone
Erythromycin– not used in horses above one yr of age since it may cause fatal diarrhea. In foals hyperthermia, diarrhea, increased sensitivity to heat and bright sunlight.
Dipyrone – very mild NSAID – may require withdrawal period in racehorses according to regulations
Cisapride _GI pain and diarrhea
Acepromazine – may cause penile paralysis (rare), hence not recommended in breeding stallions
Dysautonomia – Cats. Dysfunction of autonomic nervous system. Megaesophagus, dry mucous membranes, atonic bladder, accumulation of feces in rectum.
• Diagnosis - Histopathic examination of autonomic ganglia
• Treatment - Symptomatic (bethenecol, metoclopramide). Poor prognosis.
Dysphagia: Difficulty in prehension, mastication or deglutition. Conditions associated with prehension are trauma to lips or buccal muscles, photosensitization of lips, snake bite, jaw and teeth disorders, CNS disorders (yellow star thistle and Russian knapweed poisoning), peripheral nervous system disorders (direct trauma to nerves), etc. Conditions associated with mastication include teeth and jaw disorders, Temporomandibular joint disorders, mastication muscle disorders (tetanus, cauda equine neuritis), tongue disorders (foreign body), stomatitis (NSAID toxicity , plant awns, vesicular stomatitis and neurological or muscular deficits. Conditions associated with swallowing are CNS (rabies, botulism, viral encephalitides, moldy corn poisoning), peripheral (guttural pouch mycosis, chronic lead poisoning, guttural pouch empyema, fractured stylohyoid or temporal bones), space occupying lesions (neoplasm, retropharyngeal lymph node enlargement, distended guttural pouches), Congenital defects, choke, iatrogenic disorders etc.
Dyspnea: Inspiratory dyspnea results from upper respiratory disorders. Associated with a prolonged and noisy inspiratory effort. Conditions include stenotic nares, nasal cavity obstruction, nasopharyngeal polyp (cats), elongated or edematous soft plate, laryngeal disease, cervical tracheal disease, etc. Expiratory dyspnea results from lower respiratory tract disorders. Inspiratory and expiratory dyspnea is present in animals with lower airway or pulmonary parenchymal disease. These include thoracic tracheal disease, pneumonia, pulmonary edema, pulmonary thromboembolism, pulmonary contusions, pulmonary neoplasia, and pulmonary granulomatosis. Rapid and shallow respiration with muffled breath sounds on auscultation is present with restrictive or pleural space disorders. These include pleural effusion, pneumothorax, congenital thoracic wall abnormalities, thoracic wall trauma, thoracic wall or mediastinal neoplasia, diaphragmatic hernia, extreme obesity, marked ascites, severe hepatomegaly, large intraabdominal mass, severe gastric distention. Miscellaneous disorders include anemia, methemoglobinemia, cyanosis, compensation for metabolic acidosis, heatstroke, damage to CNS, neuromuscular weakness, pain
DX- from detailed history and radiographs. Tx: First stabilize animal, then elimination of primary cause
Dystocia management: Difficult birth may result from myometrial defects, metabolic abnormalities such as hypocalcemia, inadequate pelvic diameter, insufficient dilation of the birth canal, fetal hormone (corticosteroid) deficiency, fetal oversize, fetal death, or abnormal fetal presentation and posture.Dystocia higher in primiparous animals.
Bitches – calcium gluconate in case of hypocalcemia.
Queens Uncommon – uterine inertia, malpresentation, sometimes associated with fetal malformation in FeLV and FIV. Tx- oxytocin in case of uterine inertia.
Guinea pigs If not first bred before 7 months of age, the pelvis does not widen enough, and C-section becomes necessary.
Cattle Most common presentations -Head anterior to pelvic inlet and forelimbs in the vagina or
Head engaged and retained in the vagina and digits protruding from vulva. Correct position and deliver. More cases of dystocia in winter (due to lack of exercise) than in summer.
Swine Uncommon -uterine inertia, maternal excitement, fetal malpresentation, etc. Excessive fatness during pregnancy predisposes to dystocia.
Ovine/ Caprine - Dystocia is associated with multiple births. Yearling ewes and ewe lambs are more susceptible than mature ewes. Obesity and lack of exercise during pregnancy are important factors
Equine Tight vaginovestibular sphincter in primiparous mares. If chorioallantois separates early and appears at the vulva (‘red bag’) it is an emergency, and the foal maybe dead.
Early embryo loss (cattle) – PD +ve, later –ve, means EE loss.
• Trichomonas fetus – Protozoan. Herd infertility, prolonged calving season, ↓ed calving rate. Post service pyometra indicates this dz. Causes vaginis and endometritis, but embryo dies only 50 days post breeding. Most cows free of infection 3mo after breeding so dx directed at bulls (carriers). Look in penile crypts, prepuce and anterior urethra. Bulls > 4yo chronic carriers, younger may recover. Dx- dark field microscopy. Dimonds medium for culture ( 3 min). Females use Pyometra fluid, males use preputial smegma. Any +ve test is dxic. Tx – sexual rest for female. Ipronidazole may cause sterile abscess at inj. site.
• Campylobacter fetus – Infertility,EED, delayed return to estrus, prlonged calving season, occasionally abortion. Great variations in gestation lengths. Repeat breeding. Via coitus and fomites. Cows systemically normal but have purulent endometritis. Bulls produce normal semen. Dx – Take bulls preputial washing, culture quickly or wont grow. Use clarks medium. Ist +ve is dxic. Test breeding heifers accurate but impractical. VMAT (min 10% of herd sampled) test also used. IgA Abs may be detected in mucus. Tx – vax as soon as dx (both infected and in contact). May remain carries but fertility improves wth vax. For bulls streptomycin inj and topical once. Cc - AI
Ear mites (cats) – otodectes cyanotis. Cotagious. Severe inflammation of ears. Dx – otoscope, ear swab. Tx – parasiticides.
- Notoedres cati. rare, found on face esp around ear. Stray cats in poor condition. ZOONOTIC. Affects palm and back of hand esp in young children.
- Felicolasubro stratus – usu in long haired cats. ZOONOTIC. Itch in elderly.
Echinococcus granulosus – Adult stage resides in intestine of wild or domestic canids. Eggs passed in feces are ingested by herbivores. ZOONOTIC.
ECG – Recording of electrical activity of heart that reaches the body surface. Sum of electrical activity, relative voltage.
• P wave – Atrial depolarization (firing of SA node)
• QRS complex – Ventricular depolarization (AV node - bundle of His – purkinje fibers)
• T wave – Ventricular repolarization (diastole, membrane potential restored)
• PR segment – AV nodal delay (conduction time through atria)
• ST segment – Refractory period; ventricles contracted and empty
• TP interval – Repolarized, waiting for next P. Ventricles relaxed and filling.
• QT interval – Total time of ventricular electrical activity.
Edema subcutaneous– Dogs.
Decreased capillary integrity – Inflammation, vasculitis (infectious, immune mediated), Allergy, trauma, burns.
Change in tissue gel – Myxedema, cachexia
Non inflammatory ↑ in tissue fluid
• Decreased plasma oncotic pressure – hypoalbminemia, ↑ed loss (renal, GI, wounds, body cavity), decreased production (hepatic insuff), vasculitis.
• Lymphatic hypertension or obstruction – surgical or traumatic, neoplasia, LN inflammation. Ventral edema. Enlarged lymphnodes.
• ↑ed capillary hydrostatic pressure –
-Venous hypertension (venous obstruction, RHF, overhydration). Can be x by measurement of CVP by a catheter and a manometer.
-Arteriolar hypertension (hyperaldosteronism, ARF).
Essentials for edema : measure plasma and urine, CBC, BC.
Edema disease – pigs – aka bowel edema/gut edema or E.coli enterotoxemia. Affects healthiest animals 1-2 wk post weaning. CS – Healthy piglets suddenly dying. Periocular edema, facial swelling, open mouth breathing. CNS signs. Lesions - gelatinous edema of skin and stomach (glandular cardia). Fibrin strands in peritoneum. Histo – focal encephalomalacia of brain stem (unlike water deprivation toxicosis. Pure culture of SI and colon yields a lot of E.coli. tx ineffective once see signs.
Effusions - ascites
• Pure transudate – oncotic pressure. Hypoalbuminemia - < 0.8g/dl ( hepatic insufficiency, Glomerular dz, GI loss, chronic starvation.
• -Sustained portal hypertension due to chronic hepatic dz.
• Modified transudate - hydrostatic pressure. Acute portal hypertension due to obstruction. Hepatic disease , right heart failure, abdominal neoplasia.
• Nonseptic exudate – Inflammation. Nondegenerate neutrophils. Uroabdomen, biliary tract rupture, FIP, neoplasia, Pancreatitis, Circulatory compromise.
• Septic exudate –Septic inflammation. Degenerate neutrophils and bacteria. Bowel rupture or ruptured abscess.
• Bilious effusion – Brown/green exudate.
• Chylous effusion – Milky white/pink opaque, variable cellularity (lymphs/neuts). High triglycerides (fluid>sera by 2-3:1), cholesterol less then in serum.
Egg Binding – In birds that are laying a lot or in older birds that have never laid before. Causes space occupying mass problems w/ MS, GIT, Resp. Palpable eggs or visualized on rads. Tx w/ following: 1) warmth, 2) humidity, 3) support (steroids, fluids), 4) Ca++ injection, 5) oxytocin injection, 6) repeat Ca++ injection, 7) repeat oxytocin injection, 8) express egg in small bird, 9) 12 cc syringe and needle to suck out egg contents, 10) surgery if large bird.
Egg related peritonitis of birds - Common cause of sporadic death in layers.
Ehrlichia canis – Vector is Rhipicephalus sanguineus, brown dog tick. Seen as coccoid bodies in the cytoplasm of WBCs. Monocytes affected most frequently. E. platys often concurrent infection; usu asymptomatic is alone.
• Clinical findings - Signs arise from involvement of lymphoreticular and blood system. Thrombocytopenia, bleeding tendencies, stiffness, generalized lymphadenopothy, splenomegaly, fever. Associated w/ benign lymphocytosis and monoclonal/polyclonal gammopathy.
• Diagnosis - IFA, demonstration of organisms in WBCS, clinical signs.
• Treatment – Doxycycline. Tetracycline. Chloramphenicol is acceptable tx as well.
Ehrlichia equi – Vector unknown. Found in neutrophils. Fever, anorexia, depression, limb edema, petechiation, icterus, reluctance to move. Dx by cytoplasmic inclusion bodies. Tx w/ oxytetracycline.
Ehrlichia risticii- see Potomac horse fever
Electric shock and mouth burns (dogs and cats) – Affects tongue, lips, buccal mucosa and palate. May cause circulatory collapse due to heart fibrillation and dyspnea due to pulmonary edema. Lavage with chlorhexidine.
Dogs – mostly aortic valves of male GSD and large breeds ~ 5yo. Soft diastolic murmur heard on left heart base. Arterial pulses bounding. Streptococcus, Staphylococcus, E.coli, Klebsiella. Usually due to dental disease, Pyoderma, prostatitis. Left heart enlgmt. Px bad.
- Discospondylitis is a common sequela. Irregular lytic vertebrae.
Horses – Mostly mitral valve. Systolic murmur over left cardiac apex. Streptococcus, actinobacillus equlli. Left heart enlgmt.
Cattle – tricuspid valve. Right heart enlgmt.
Cats – rare
• Clinical signs – Chronic fluctuant fever, heart murmur, shifting leg lameness, Malaise and wtloss, signs of systemic embolization.
• Diagnosis - Echocardiogram., neutrophilic leukocytosis. Rads show alveolar pattern & ECG shows tall R waves(LV enlgmt) & wide P waves (LA enlgmt) in LSHF. Positive blood/joint culture with demonstration of heart involvement.
• Treatment - High dose broad spectrum antibiotics. Tx HF. Cc - prophylactic BSAB.
Endocardiosis – degenerative valve disease – most common cardiac disease in animals.
Dogs – left AV (mitral) valve. Small breed old dogs.
Cats – left AV (mitral)valve. uncommon.
-In all cases, leads to mitral regurgitation and pulmonary edema. Dilates LA, leads to APCs, Atrial fibrillation, sustained tachycardia. May cause LA rupture. RATS is activated.
CS – exercise intolerance, tachypnea followed by cough and dyspnea. Prominent murmur and a precordial thrill. Also see cardiac dz.
Horses – left AV (mitral) valve and aortic valves( grade 2-6 murmur at left 4th i/c space).
Horses are usually asymptomatic.
Endotoxemia (horses) – mostly due to damage to GIT (enteritis, colitis, ischemia). Signs of abd pain, fever, ↑ HR, ↑ RR, ↑ CRT, change in mm color and depression. Tx with flunixine meglumine, polymyxin B/ plasma, balanced fluids.
Enema – Phosphate enemas should not be used in cats as can precipitate potentially fatal hyperphosphatemia, hypocalcemia, and hypernatremia.
Enteroliths (horses) – form around FBs. More likely when GIT has high P and high pH. Mostly made of Mg, ammonium, phosphate. If single, large and in large colon, will have h/o chronic intermittent colic. If small, and in small colon, will cause slower onset but more severe colic and may rupture the GIT and kill the horse. Exploratory surgery, rads.
Enterotoxemia of adult sheep and lambs – see pregnancy ketosis.
Eosinophilic Granuloma / Eosinophilic dermatitis – cats, dogs, horses.
Cats - Insects, env, diet.
• Eosinophilic ulcer – Nonpruritic. Found on upper lip. Histo shows ulcerative dermatitis with infl. cells. Red. Tissue or peripheral eosinophilia uncommon.
• Eosinophilic plaque - found on medial thigh and abd. Extremely pruritic. Red. Regional lymphadenopathy seen. Histo shows eosinophilic dermatitis with peripheral eosinophilia.
• Eosinophilic linear granuloma - on mouth or legs. Yellow to pink lesions. Found anywhere. Caudal thigh location is linear. Histo shows granulomatous inflammation around degenerative collagen. Marked tissue and peripheral eosinophilia esp when lesions on mouth.
-Tx corticosteroids (met.pred., traimcinolone), and underlying cause. Abs ( A-C, ceph, enro).
Epiglottic Entrapment – Equine. Slight exercise intolerance, inspiratory and expiratory noise. Dx via endoscopy, shape of epiglottis still visualized (unlike DDSP). Tx by splitting ariepiglottic fold. Surgical excision via laryngotomy, transendoscopic laser axia division, or oral w/ hook or laser.
Epizootic Bovine Abortion - Foothill abortion. Agent unknown. Infectious disease of cattle manifested by abortion (3rd trimester) or weak calves. Endemic in foothills of California, Nevada, and southern Oregon. Vector is Pajaroello tick, Ornithodoros coriaceus. Aborted fetuses have enlarged and nodular liver, edema, erythema, petechial hemorrhages.
Epizootic abortion of ewes – see abortions
Equine Cushings disease – Usu dt pituitary tumor in middle age to old horses. PU/PD, abnormal heavy curly hair growth which does not shed in the summer, swayback stance and a pot belly, deposition of fat above eyes, depression, poor condition, polyphagia, chronic laminitis, Loss of muscle over the topline, recurrent infections.
Tx: Cyproheptadine, Pergolide mesylate effective but can worsen the chronic laminitis of Cushing’s disease.
Equine Encephalomyelitis – Arbo virus. Togavirus. Sleeping Sickness. EEE, WEE, VEE. Causes CNS dysfunction, mortality. Transmitted by mosquito-vertebrate (bird)-mosquito cycle in late summer and fall. EEE – most potent. VEE can go from horse to horse via respiratory droplets. Virus travels via lymphatics and replicates in M and neuts. ZOONOTIC – all 3 can cause mild flu-like symptoms to death, usu follow equine infection ~ 2 wks. VEE from horse man. Use repellents.
• Clinical signs – Fever, altered mentation, impaired vision, aimless, head pressing, circling, can’t swallow, ataxic, paresis, paralysis. Motor irritation, sensitivity. Lymphopenia, leukopenia.
• Diagnosis – Clin sx, hx, season. Serology, paired sera. Virus isolation.
• Treament and Control - Supportive care. Vax valuable horses in mosquito area 2x/yr. EEE and WEE killed w/ sht term immunity. VEE – MLV, long term immunity.
EHV1 – Equine viral rhinopnemonitis
EHV2 –Respiratory disease only.
EHV3 – Equine coital exanthema. Benign veneral disease of both sexes. Causes red nodules on genital mucosa. In mares 4-8 days post service or rectal exam. Spreads only in acute phase of dz. Dx by virus identification from periphery of lesion. Sexual rest. Prevent sec inf.
Equine Infectious Anemia – aka swamp fever. tm by transfer of blood. Persists in WBC for life. Usu sporadic but outbreaks if abundant flies +nt.
• Clinical findings – Suspect if there is h/o intermittent fever, depression, anemia, wtloss or a group develops signs after new entry. Vasculitis. Shed in all secretions when acute. PCV and platelets fall, monocytes↑ and spleen enlarges in acute cases. In chronic cases, blood has stainable iron with ↑ed γ globulin, spleen and LNs enlarged. Carcass pale and emaciated.
- histo shows ↑ed RE cells and ↑ed hemosiderin in kupffer cells.
• Diagnosis - Coggins test. Can get a false positive if foal's dam was infected. Such foals should be isolated till free of inf. Recently infected horses may test –ve for 1wk.
• Cc – isolate permanenty and control flies.
Equine Influenza Virus – 1-2 yr old horses. Many different strains. Sudden onset of fever, explosive dry cough, serous nasal dischg. Usally self-limiting, tx w/ rest and supporting care. Worry about 2 infection and time away from training.
Equine LMN Disease - ~ resembles Lou Gerhrig’s Disease (ALS) of man. >2yo. Prolonged vit E def and no access to pasture may cause this. Slowly progressive (1-2mo) w/ muscle fasciculation, muscle wasting, lays down, raised tail bowed head.. Constant wt shifting on hindlegs. Debilitation w/ good appetite. Excessive sweating. Eye exam may show brown streaks. Dx by biopsy of tail (sacrocaudalis ms) and accessory spinal nerve. Mild ↑ in ms enz. No treatment. May stabilize but do not recover.
Equine Protozoal Myelitis – Sarcocystis neurona, sporozoan parasite. #1 neuro disease of equine. Mainly affects brain, brainstem and SC. Opossums(DH) → birds (IH)→ horses (dead end host). Horses eat opossum feces or contaminated feed/water. Sarcocystis invade CNS. Subtle, slow onset, progressive. GREAT MIMICKER. Multifocal, asymmetrical, progressive spinal cord disease. Weakness, malposition of a limb, muscle atrophy, spinal ataxia or "wobbling", head tilt with asymmetry of the face (eyelid, ear, lip), may be down and unable to rise. Lameness not traceable to orthopedic disease. Focal area of mm atrophy. Dx via serology (just show exposure not dxic), CSF testing by western blot shows Abs (most useful), parasite DNA detection. Tx w/ folic acid antagonists – TMS plus pyrimethamine. New drug is toltrazuril. Guarded px.
Equine Viral Arteritis - Togavirus. Tm respiratory and venereal routes.
• Clinical findings - Mostly subclinical. If acute, contagious, viral disease characterized by fever, depression, dependent edema (especially of the hindlimbs, scrotum, and prepuce in the stallion), conjunctivitis, nasal discharge, and abortion with partially autolyzed fetuses (3-10 mo) with no other lesions.
o Epidemics occur on race track where large no of horse are kept together. Significant stallions become carriers and maintain infection.
o Vascular lesions are endothelial swelling and degeneration, thrombosis and necrosis.
• Dx – nasopharyngeal and conjuctival swabs and unclotted blood for isolation. Carrier state confirmed by demo of virus in semen. If dead, submit body fluids and lungs.
• Tx – not needed. Recover spontaneously. Just support. Vax.
Erysipelas – Erysipelothrix rhusiopathiae bacteria found in water, soil, decaying matter, slime on fish, etc. Causes swine erysipelas, nonsuppurative arthritis in lambs, postdipping lameness in sheep, acute septicemia in turkeys, ducks. In man, usu localized termed erysipeloid (not same as strep infection erysipelas in man).
• Clinical signs – Growing pigs. Acute septicemia, skin (subacute) form, chronic arthritis and joint effusion, vegetative endocarditis. Death. High fever, walk on toes, squeal. Skin discoloration w/ erythema, diamond-shaped skin lesions, sloughing earstips and tails. Enlarged ln and spleen, edematous and congested lungs.
• Diagnosis – Dx w/ tx of penicillin – response seen w/in 24 hrs. Diamond shaped lesions are diagnostic. Necropsy.
• Prevention and treatment – Immunization. Antiserum. Penicillin. Eliminate carriers, good sanitation, regular vax.
Erythema Multiforme - Unknown cause, likely immune complex. Reaction pattern of drug eruption. Characterized by erythematous papules on the skin of the abdomen that expand peripherally leading to the development of annular lesions with normal centers. Occurs in pigs and other species. Treat with prednisone. Toxic Epidermal Necrosis is severe whole body EM.
Escherchia coli infection–
• Cattle – +nt in GIT. Diarrhea, dysentery in young cattle, mastitis in older.
• -Calves – enterotoxigenic colibacillosis in 4-7 day old. Vaccinate cow w/ K99 antigen vax.
- Adults – Pyelonephritis and cystitis esp chronic infections. Usu follows Corynebacterium renale and is dt ascending infection from stress, peak lactation and high protein diet. Discomfort while urinating. Dx h/o recent parturition, kidney enlgmt. Tx genta, not in food producing animals.
• -E.coli O157 +nt in GIT of cattle. ZOONOTIC. Ground beef most common source esp if improperly cooked. Also by unpasteurized milk, cont. water.
• Pigs – most imp 1o cause of diarrhea in piglets <5 days age. Watery to yellowish brown pasty diarrhea, dehydration, acidosis and hyperkalemia. Dx –CS, age, pH of feces (>8 due to HCO3). Gentamycin, neomycin, oral antiserum. Cc – vax on feed of sow.
Esophageal obstruction - all animals see choke.
Esophageal Stricture – Due to FB, may follow previous episode of choke. Mostly occur at thoracic inlet. Balloon, do not cut.
Esophageal Tumors – Rads w/ mass in chest at proper region could be in esophagus. 1) Fibrosacrcoma = Spirocerca lupi. 2) Leiomyoma usu at lower esoph sphincter, esp in beagles. Treatable. 3) Carcinoma, uncommon.
Esophagitis (dogs and cats)– Occurs post anesthesia dt gastroesphogeal reflux. Tetracyclines can cause (esp Doxy). Atropine and acepromazine can ↓ tone. Acute or chronic vomiting. Toxins, irritants, intubation, spirocerca lupi can cause also, cat lay on disinfectant than like clean. Regurgitation, swallowing attempts, head extension. Follow oral meds w/ water/food. H1 blockers. Soft food low in fat 3-4 tid.
Estrogen Therapy – For mismating in canines. Many side effects, younger (< 4 yrs) are more tolerant. See bone marrow toxicity (aplastic anemia), 30% chance of uterine infection, longer heat. Success rate directly related to time b/w mating and onset of tx.
Ethmoid Hematoma – Unilateral epistaxis dt ethmoid turbinate mass, not exercise induced. Usu in middle aged horses. Dx w/ endoscopy. Repair with sinus flap. More contemporary tx is inject w/ 10% formalin or ND:YAG laser to burn off. Bloody procedure. Ddx – gutteral pouch mycosis. If bilateral epistaxis, ddx EIPH or FB.
Ethylene Glycol Toxicity (dogs and cats) – Antifreeze. Results in calcium oxalate crystal formation and acute renal tubular necrosis resulting in pale kidneys w/ swollen cortices on necropsy. Glycolic acid is the main toxin.
• Clinical signs – 1st stage see CNS signs (ataxia, seizures), drunk, vomiting, PU/PD. Appear to feel better then 2nd stage of cardiopulmonary signs (mild or absent tachycardia or bradycardia). 3rd stage is oliguric acute renal failure, acidosis in 36-72 hrs. signs of ARF.
• Diagnosis – normochloremic metabolic acidosis, increased anion gap, isosthenuria, serum hyperosmolality, calcium oxalate crystalluria(mostly six sided prisms). On U/S, see renal cortical echogenicity. Swollen and painful kidney. If anifreeze has flourescene, will glow under woods lamp. Hyperphosphatemia with antifreeze that contains rust inhibitors, but it will resolve before RF starts, recurs when azotemia occurs.
• Treatment - IV ethanol(TOC in cats) or 4-methylpyrazole(TOCin dogs, ineffective in cats) to inhibit ethylene glycol metabolism. NaHCO3. Use 0.3 – (0.5 x bwt in kg) x (24 – plasma bicarbonate) = reqd bicarbonate in Meq. Must be w/in 8 hrs of ingestion.
- If azotemia or RF +nt, the no use of ethanol or 4-methylpyrazole. Px is bad.
Euthanasia – in brackets are conditionally acceptable methods.
Birds –Inhalant anesthetics, CO, CO2, barbiturates. (N2, argon, cervical dislocation, decapitation )
Cats - Inhalant anesthetics, CO, CO2, barbiturates. (N2, argon)
Dogs - Inhalant anesthetics,CO, CO2, barbiturates. (N2, argon, electrocution, penetrating captive bolt)
Ferrets, mink - CO, CO2. (N2, argon, electrocution or stunning, then cervical dislocation).
Fish -Tricaine methane sulfonate (MS-222) or benzocaine in tank water. (Stunning and killing blow, stunning and decapitation, cervical dislocation, pithing).
Horses - Barbiturates, chloral hydrate, chloral hydrate/MgSO/ pentobarbital. (Penetrating captive bolt and exsanguination, gunshot, electrocution).
Nonhuman primates – Barbiturates. (CO, CO2, N2, argon).
Rabbits - Inhalant anesthetics, CO, CO2, barbiturates. (Cervical dislocation then exsanguination, decapitation, penetrating captive bolt)
Reptiles - Barbiturates, inhalant anesthetics, CO2. (Gunshot, penetrating captive bolt, stunning and decapitation, decapitation and pithing).
Rodents and other small animals - Inhalant anesthetics, CO, CO2, microwave irradiation, barbiturates. (CO2, CO, N2, argon, decapitation, cervical dislocation).
Ruminants – Barbiturates. (Gunshot, penetrating captive bolt or electrocution followed by exsanguination).
Swine - Barbiturates, CO2. (Inhalant anesthetics, CO, penetrating captive bolt, gunshot, electrocution)
Zoo animals - Barbiturates, CO2. (Inhalant anesthetics, CO, penetrating captive bolt, gunshot)
Exercise Induced Pulmonary Hemorrhage – Blood from lungs (caudodorsal lung field) as consequence of exercise. Horses with a h/o repeated bouts of severe EIPH have extensive bronchiolitis in the dorsal regions of the caudal lobe with concurrent bronchial arterial neovascularization, interstitial fibrosis, and sequestration of macrophages containing hemosiderin (hemosiderophages). See epistaxis, gurgling, swallowing, exercise intolerance. Endoscopy (60-90 min after exercise), see blood in airways . If you suspect EIPH but can not do endoscopy, examine TB asp for hemosidin containing macrophages. DDx - guttural pouch mycosis and ethmoidal hematoma.
Tx: ineffective. Symptomatic. Frusemide, conjugated estrogens, vitamin K, and vitamin C used for prevention but not very effective.
Exertional Rhabdomyoloysis Syndrome – Monday morning disease, Tying up. Most common muscle disorder in horses affecting all breeds, usually > 2 yrs. More common in females. Excess carbs in diet implicated. Polysaccharide storage disease is a subset.
• Clinical signs - Stiffness and gait alterations to severe ms cramping and immobility, profuse sweating, firm ms groups, myoglobinuria if severe.
• Diagnosis – Clin signs, CPK, AST. Mild metabolic alkalosis (NOT lactic acidosis), Cl-, Ca++, fractional excretion of K+, myoglobinuria. Muscle biopsy dx some subsets. Ddx iliac thrombosis.
• Treatment – REST. Supportive. Phenytoin in chronic myopathy. Dantrolene sodium best as preventative, little to relieve current signs.
Exocrine Pancreatic Insufficiency (dogs and cats)– Maldigestive syndrome usu dt pancreatic atrophy. Common in GSD and collies. Not dt pancreatic tumor! Chronic SI diarrhea(voluminous, greasy, foul smelling), ravenous appetite, wt loss, dry hairoat. PU/PD seen if DM also +nt. May see slate gray feces. Often have concurrent bacterial overgrowth. Test w/ serum TLI and fat in feces. Check TLI on any dog w/ non PLE SI diarrhea. Never eliminate EPI based upon failure to respond to replacement enzyme therapy. Fecal proteolytic enzyme test useful in cats. Tx enzymes. Cats may need cyanocobalamin injections. Highly digestible low fat diet.
Exudative epidermitis – pigs - Staphylococcus hyicus plus fighting. Also by vertical tm. Normally +nt on body. 3-20 kg typically. chronic form in adults. Usually affects late preweaning to early postweaning stage (5 – 60 day old pigs). Extends rapidly, covering the whole body. Anorexia, dehydration and death in 7-10 days. If chronic, patches 3-5 cm of the above skin condition (upper neck and hind legs - areas where the pig’s fight) but does not spread. Piglets may have facial necrosis due to fight for milk. Sows may have a chronic black spotty appearance on the back and neck.
Dx: Clinical exam. Culture meaningless. DDx Severe Pityriasis rosea, parakeratosis dt zinc deficiency, Mineral def dt milling error.
Tx, Cc - Isolation, lincomycin, penicillin, OTC, disinfectant baths (Lanolin). Control fighting and its causes. In herd ‘outbreaks’ add lincocin to the water supply.
Eyelid disorders – covered under ophthalmology
Failure of passive transfer (cattle) - Common in Holstein (poor colostral quality). Poor colostral quality or quantity(first lactation, colostral volume, premature calving or induction of parturition, premature lactation), Ingestion failure (poor udder or teat conformation, poor mothering ability, maternal periparturient disease, poor neonatal vigor, congenital musculoskeletal abnormalities), Absorption failure(neonatal asphyxia (dystocia), method of feeding, extremes in environmental temperatures, absence of dam, prematurity). Increased infectious diseases morbidity and mortality, increased duration of pathogen shedding, decreased weight gain, starvation, decreased milk production into first lactation.
Dx istory, Immunoglobulin concentration: IgG is less than 1000mg/dl, Total serum protein (TSP) < 5.0g/dl, Zinc sulfate & sodium sulfate turbidity (if more precipitation the higher the Ig concentration). GGT if > 300IU/L means calf has consumed colostrum.
Tx : dx within 12 hrs. of birth: oral IgG. In Holstein calves at least 2.0 L colostrum via esophageal tube for first feeding. In other breeds should be the amount equal at 10% of their body weight in the first 24 hrs., with at least 2 L being fed in the first 6 hrs. of life. If dx within 18 hrs. or more, IV IgG using BT (2.5 L).
False Hellibore – Veratum californicum. Alkaloid causing cyclops in cattle.
Fasciola hepatica - Liver fluke. IH = snail. Flukes create tissue damage in liver and bile ducts. May cause icterus.
Fat cow syndrome and subclinical fatty liver - Most common in periparturient cattle and usually accopanies periparturient disorders. Increases likelyhood of ketosis. Negative energy balance. Occurs when blood NEFA are increased (most dramatic increase at calving). Gets worse if cow goes off feed. NEFA go to liver, are either oxidized [forms CO2, ketones (aceto, BHB), esp when hypoglycemia +nt] or esterified (forms triglycerides, likely to accumulate). Energy consumption above requirements will not directly result in fatty liver, but only if cow gets overconditioned, obese and, then reduces feed intake.
Dx Liver biopsy only reliable method. Liver floats in CuSO4. tx none. Avoid overconditioned cattle, rapid diet changes, unpalatable feeds, periparturient diseases, and environmental stress. Careful 1 wk before calving. Glucose or propylene glycol IV before calving may prevent. Cows should enter the dry period with an average body condition score of 3-3.5. Thin cows (≤2.5) fed additional energy during the dry period to improve condition without fear of causing fatty liver. Overconditioned cattle (body condition score of ≥4.0) should not be feed restricted as it will increase fat mobilization.
Feather picking in birds - Destroy most feathers can be reached with its beak, so head is spared!. Gets prone to skin infection, systemic infection, ill-thriftyness, debilitation, increased suseptibility to infections, a substandard immune system responsiveness. Causes : Medical - parasites (internal or external), metabolic/ organic diseases, benign or neoplastic masses, various infections, malnutrition, localized or generalized pain, a surface defect. Behavioral- sexual/hormonal frustrations, changes in the env, perceived or real changes in attention, Stress, real or imagined. tx the cause or keep sedated.
Feline Acne - Comedones, or blackheads, on a cat’s lower lip, face, and chin. Overproduction of oily secretions, can then lead to acne. Very prominent on white or pale colored cats. In mild cases, hair follicles of chin and mouth are clogged, forming blackheads. Sec inf may follow. In severe cases, inflamed, swollen, cystic, or scarred. Persians particularly susceptible to idiopathic Persian facial dermatitis, or “dirty face” (symmetrical pattern of waxy black material on the hairs of face and chin).
Tx: removal of excess sebum to prevent comedone formation and sec inf. Can progress to furunculosis. Best AB are amoxicillin/clavulonic acid and cephalosporins. Enro also effective.
Feline Endocrine Alopecia - Bilateral symmetrical hair loss on the posterior abdomen, inner thighs, perineum of male neutered cats. Sex hormone deficiency suspected. Rare.
Feline enteric coronavirus – self limiting diarrhea in cats.
Feline Immunodeficiency Virus – Lentivirus (retrovirus). Lifelong infection. Mature outdoor adult cats. Tm by bite wounds (not by non-aggressive contact). May appear normal for years, but eventually kills. Prblem caused by sec infs.
CS: enlarged lymph nodes initially. Deteriorates progressively or recurrent illness interspersed with periods of relative health. Poor coat condition and persistent fever, gingivitis, stomatitis, and chronic or recurrent infections of the skin, urinary bladder and URT, persistent diarrhea, eye infections. Slow but progressive weight loss followed by severe wasting late in the dz. Neoplasia get more common, and may cause NS.
Dx: ELISA to screen, Western blot to confirm on serum or plasma. False positive - Kittens born to infected mothers for several months. Few become infected. Kittens < 6 mo with +ve results are retested at every 2 mo till 6 mo old. False Negative - takes 8-12 wks to get detectable levels of Ab so -ve in this period. So -ve cats with h/o bite by unknown cats are retested again 2 mo later.
Tx: No optimal antiviral therapy (AZT is the best). tx sec dz and inf. Dilute bleach for disinfection. Vax new cats or kittens.
Feline infectious anemia – see hemobartonellosis.
Feline Infectious Peritonitis – Coronavirus. Young and very old cats. Remains infectious in env up to 6 wks but easily killed by disinfectants. Feces most common route. Shed in secretions and excretions( sometimes asymptomatically). Risk factors included popu density, amt of shedding, breed (persians, birmans predisposed). Feline Enteric Coronavirus usu causes mild, self-ltg diarrhea in young cats. Some FECV mutate to FIP. Biphasic - <6-12 wks old or >13 yrs old. FeLV, stress, crowding, concurrent diz risk (steroids affect humoral immunity and do NOT risk). Up to 50% are FeLV+.
• Clinical Signs –Effusive FIP – fluctuating, AB responsive fever; lethargy, anorexia, wt loss; ascites (pot belly), pleural fluid, pericardial and scrotal fluid accumulation rarely. Noneffusive FIP – same, but instead of fluid accumulation, have pyogranulomatous rxn → local tissue necrosis and ↓ed organ fn (any organ). Also see serious ocular changes (uveitis and chorioretinitis ) and CNS changes (neuropathies). Death imminent after CS appear.
• Diagnosis – Hyperproteinemia, kidney/liver abn. Hyperglobulinemia and thrombocytopenia. Keratitic ppts in eyes. Ascites fluid is thick, straw colored, pyogranulomatous nonseptic exudate w/ moderate cellularity and high protein levels. On smears, background has characteristic eosinophilic stippled appearance. FECV serology not helpful. Antibody tests crossreact with enteric coronavirus antibodies. Do not do FIP Serology.
• Treatment – None. Immuno suppression.
• Prevention – Env control. DO NOT use vax – sensitizes cat to infection.
Feline Leprosy – Mycobacterium lepraemurium.
Feline Miliary Dermatitis - A papular, crusting skin disease located predominantly on the back with varying degrees of pruritus. Ectoparasites, food allergy, drug allergy, fungal or bacterial infection. Feline flea allergy.
Feline Panleukopenia – Parvovirus. aka Distemper. Similar to canine parvo. Cerebellar hypoplasia. Vax.
Feline upper respiratory disease complex - Illness typified by rhinitis, conjunctivitis, lacrimation, salivation, oral ulcerations. By feline viral rhinotracheitis (herpes) and feline calicivirus. Feline pneumonitis (chlamydia) and mycoplasma are less important.
Feline Viral Rhinotracheitis – Herpesvirus. Affects conjuctiva and nasal passages. Fever, sneezing, bilateral conjunctivitis, rhinitis, salivation, fluctuating fever. O/N discharge (s → p). Excitement or movement induces sneezing. Ulcerative stomatitis, ulcerative keratitis in debilitated cats. INIBs. Tx corneal ulcers w/ topical acyclovir. Lysine. Avoid sec inf. Vax.
Feline Calicivirus – Loves oral mucosa and LRT. Ulceration of oral mucosa. Serous rhinitis, bilateral conjunctivitis. No inclusions. Vax.
FCV may produce alt leg lameness with pain and fever in kittens which resolves on its own. May occur with FCV vax. No URT signs.
Feline Pneumonitis – Chlamydia. Chronic, low grade conjunctivitis (one eye initially, other eye later). ICIBs. Dx by Giemsa stained conjuctival scarappings. Tx w/ tetracycline.
Mycoplasma – Severe edema of conjunctiva and a less severe rhinitis. Dx as chlamydia. Extracellular coccoid bodies on conjunctival epithelial cells.
Feline Stomatitis - Causes include feline herpes, calici, FELV, and FIV. See Dentistry section.
FeLV – Retrovirus. Young cats < 4mo. Tm - Contact w/ body fluids is most common way (intimate moist contact must). Also bite wounds, blood transfusion, transmammary and trans placental. 1/3 of cats exposed become persistently viremic and develop FeLV-related disorders. 2/3 of cats resist development of persistent viremia. 1/3 of transiently viremic cats become latently infected, virus hides and re-expresses later in life. These cats are not carriers and do not spread infection, test –ve.
- can cause neoplasia (esp. thymic, multicentric & hepatosplenic lymphosarcoma).
• CS – non reg anemia, liver dz, intestinal dz and repro problems. Lymphosarcoma and leukemia. Chronic resp inf, chronic gingivitis/stomatitis, FIP, poor wound healing, abscesses.
• Dx- Use Abs against p27 (core protein). IFA detects cell-associated viremia. ELISA detects serum-associated viremia and is more sensitive (detects inf earlier). Cats w/ positive ELISA should be retested 6 weeks later for seroconversion. Non core vax.
aka Feline Urologic Sydrome. 4 basic syndromes. All cause hematuria, pollakiuria and stranguria. More common in indoor obese cats. CS – animal rapidly becomes acidotic.
Urinary obstruction (cats and dogs)– Most commonly by crystalline and mucoprotein plugs in cats and by uroliths in dogs. Hydronephrosis if upper and hydroureter if lower. Signs of RF develop rapidly. Bladder is distended, painful, cant be catheterized. Bradycardias or cardiac arrhythmias dt acidosis and hyperkalemia (tall T waves, ↑ PR interval, wide QRS). Unilateral obstruction may go unnoticed. IV pyelogram and U/S necessary. NSS is fluid of choice + NaHCO3. Post obstructive diuresis common after tx.
Urolithiasis- both sexes. Gelatinous plugs mostly near urethral orifice. Main cause of obstruction. Rads and U/S are critical to detect them.
- Struvite – most common feline urolith. Can be sterile (dietary) or infected (dt UTI). Another type of sterile can form a nidus for UTI. tx UTI, ↓ pH ≤ 6, reduce dietary Mg.
-Calcium oxalate – most common feline nephrolith. Sx removal only tx. Prevent by non acidifying diet, avoid multi minerals, give vit B6.
UTI - infections
Abnormal micturition (dogs and cats) – mostly due to hormonal def in neutered males and females [(give DES in females and testosterone in males) alt. phenylpropolamine]. -Urge incontenance due to detrusor irritability associated with cystitis (give propantheline).
-Neoplasia – rare in cats. Transitional cell carcinoma most common in dogs.
-Animals with unilateral ectopic ureters may void normally and dribble intermittently. -Partial obstruction of urethra. If functional obstruction, give phenoxy benzamine).
-LMN problems (lesions in sacral SC, tama to pelvic nerve, detrusor atony). Bladder is distended but easily expressed. Give bethanecol.
-Mechanical obstruction and UMN problems (damage to thoracolumbar SC, dz of cerebrum, cerebellum or brainstem). Bladder distended and difficult to express. Relieve mechanical obstruction and express bladder manually in UMN problems.
Ferrets – Mustelidae. Most in US from Marshall Farms, tattoo on R pinna. Life span approx 4 yrs dt common diz. Hobs are males, Jills are females, have kits (gibs, sprits).
• Anatomy – Similar to cat. Can palpate everything. Change coat and body wt w/ season (lose 20% in summer). Venipuncture easy when anesth, cranial vena cava. Also jugular and cephalic vv. Ferrets have big spleens dt extramedullary hematopoiesis, esp if sick. Need to do dentals, calculus.
• Prev Med – Carnivores, 25% protein, 25% fat in diet, often feed cat food. Need constant supervision as get into everything. Need to immunize for canine distemper (premed w/ benadryl to prevent anaphylaxis) and rabies. Don’t test for heartworms but put on preventative. Spay (prevent estrogen tox) and castrate. Stinky if not neutered.
• Clin Path – Creatinine does not w/ renal failure.
• GI Diz – If < 2yrs, FB. Can dx w/ palpation; hydrate than sx. If >2yrs, hairball. Long tubular stx on palp, hydrate and sx. Gastroenteritis often dt Helicobacter musteli, causes upper GI vomiting, melena. Tx w/ pepto bismol, metronidazole, amoxicillin. Lawsonia intracellularis can cause infl of ileum/cecum; mucus. Proliferative Bowel Diz. Tx w/ chloramphenicol. Coronavirus enteritis is green slime disease, Epizootic Catarrhal Enteritis. New ferret in house, green diarrhea, ALT>700. Usu self ltg, tx w/ broad spectrum antibiotic.
• Endocrine Diz – Induced ovulators, seasonal polyestrus, prolonged estrus (risky if > 2wk). If remain in heat will die from estrogen toxicity (BM suppression, pancytopenia, bilateral symm alopecia, discharge and non reg anemia). Can bleed to death from severe thombocytopenia. Tx with hCG, induce ovulation and spay (always check CBC 1st)). If PCV less, px bad. Don’t have blood types so can give multiple BTs. Ddx from ovarian remnant by response to hCG (will respond).
o Adrenal disorders include hyperplasia, adenoma. Clin signs for female, > 2 yrs old. Bilat symmetrical truncal alopecia, redist of fat, think skin, pendulous abdomen, vulvar swelling. Endocrine panel ↑ androgens and estrogens) and U/S. ACTH stim doesn’t work (cortisol levels stay unaffected in this dz). Male, unable to urinate, obstructed urethra or enlgd prostate. Cut out to confirm, mitotane and sx to tx. R adrenal is on caudal vc. Lysodren is ACTH agonist that stops secretion from pituitary.
o Insulinoma – Most common cause of seizures in ferrets. Tumor of pancreatic islet cells. Check blood glucose. Never mets. h/o of collapse, weakness, wtloss, hypoglycemia. Tx w/ prednisolone, diazoxide. Can sx remove but recur. Keep corn syrup handy.
• Lymphoma – Like cat. Juvenile onset in < 1yr (very aggressive) or adult onset > 2yrs. Thin, cranial mediastinal mass w/ effusion, ln enlgmnt, multi-organ involvement. Dx w/ ln biopsy, usu popliteals. Try to avoid fat as ferrets pack fat around ln. Px is poor. Tx includes cyclophosphamide, vincristine, pred.
• Mast Cell Tumor – Males around prepuce.
• Infectious Diz – Green slime diz, see above.
o Influenza – Dec, Jan, Feb, exposure to human infection. Fever, URD, 2 bact infection, pneumonia. Non fatal.
o Canine Distemper – Extremely susceptible. Very fatal. Respiratory diz, crusty rash on chin, parakeratosis on nose, feet – hard pad diz. May present in status epilepticus. Vax to prevent but use benadryl 1st to prevent anaphylaxis.
o Aleutian Mink Diz – Parvo virus. Vasculitis.
• Anatrichostoma – Cutaneous nematode worm. Excoriation and erosion on dorsal cervical skin. Dx when see eggs on skin scrape. Tx w/ ivermectin.
• Cardiac Diz – DCM is #1, px grave. Also get HCM rarely. Do see Heartworm Diz – Heart failure, pleural effusion, wasting, lethargy. Posterior paraparesis, murmur. Dx w/ rads. Tx w/ pred. Cat heartguard, ½ chew tablet.
• Heat stroke –
• Pneumonia – Mainly by CD or human influenza. Sec inf follows. Rads show alveolar pattern. Cephalosporins, chloramphenicol.
• Splenomegaly –
• Sterilization – sterilize at 4-6 no age or within 2 wks of first estrus to prevent estrogen toxicity. Always check CBC for thrombocytopenia.
Fescue – Summer Fescue Toxicosis. Toxin present in tall fescue forage or seed contaminated w/ endophytic fungus, Acremonium coenophialum. Produces weight gain, milk production, and agalactia in cattle, sheep and horses. Lameness w/ cold feet and pasterns, necrotic ears and tails.
Fetal Membranes - Embryonic membranes of the dog include the chorion, yolk sac, amnion, allantois.
Fibrosarcoma (cats) - Highly malignant tumour developing at vaccination sites and originates from fibrous CT. Firm, nodular or multinodular cutaneous lesions, which are neither painful nor ulcerated. Located s/c so rarely ulcerate, except terminally. Rarely painful except when large or infiltrated with deep structures. Once dx px guarded. Even repeated sx doesnt work, die within a year. dx by PE, CBC, UA, BC, retroviral testing (for FeLV) and 3-view chest rads to check metastasis. Confirm by incisional biopsy or small wedge biopsy. DO NOT remove until sure about dx.
Fibrotic Myopathy – Equine. Trauma to semimembranosus or semitendinosus muscles. Thick tissue band that needs to be transected.
Flail Chest - Loss of stabitily of chest wall due to multiple rib fractures. Loose chest segment moves in a direction which is reverse of normal; inward during inspiration, outward during expiration (paradoxical respiration).
Flatulence – Bacterial metabolism of malabsorbed carbohydrates reaching colon.
Flea allergy dermatitis and Flea Control (dogs and cats)
Ctenocephalides canis and C. felis (most common). White legless wormlike larvae.
Most common dermatologic disease of dogs. Seasonal (more in the summer). Non seasonal in hot areas with constant flea problem. Flea development inhibited by extreme temp, low humidity and high elevations (>5000ft). Initially IgE reaction later IgG reaction. Histamine in flea saliva results in irritation and pruritis. Either immediate or delayed reaction, or both and will result in circulating IgE and IgG production. If continuously exposed, may develop a natural tolerance. Uncommon in dogs <1yr.
CS: Dogs : papulocrustous lesions on the lower back, tailhead, and posterior and inner thighs, ventral abdomen, lower back, neck and ears. May develop “hotspots” and sec lesions. Cats : mainly papulocrustecous milliary dermatitis on head and neck, alopecia and eosinophilic plaques and linear granulomas.
Dx: Age of onset, recurrent tapeworm (Diplydium caninum) infestations in dogs), clinical signs, + nce of fleas or flea excrement (reddish black, cylindrical, and pellet- or comma-shaped). Intradermal skin testing (wheal > 3 mm in dia in Immediate but diffuse edema in delayed rxn) and ELISA. Ddx from atopy, food allergy, sarcoptic or demodectic mange, other ectoparasites and bacterial folliculitis.
• IGR – Pyriproxyfen, methoprene, fenoxycarb. Eggs will not hatch; Larvae don’t pupate. Kills larvae.
• Chitin Inhibitors – Lufenuron. Prevents eggs from hatching. Larva unable to move into cocoon stage. Also gets dermatophytes.
• Imidacloprid – Kills adults. Prevents post synaptic binding of Ach.
• Fipronil – Kills adults and ticks. Inhibits GABA mediated Cl- flux.
• Pyrethrins – Quick kill. Broken down by UV light. Can be used in cats.
• Permethrins(pyrethroids) – UV stable but slower kill. Don’t use in cats !
• Nitenpyram – Capstar. Kills fleas quickly for short period of time.
• Selamectin - kills adult fleas AND prevents flea eggs from hatching for one month.
- for good control, use IGR + insecticides. Clear all hidden areas. 2.5 times more insecticide for larvae.
Flexure deformities of horses - Contracted tendons, Club foot, Knuckling. Flexor tendon disorders dt postural and foot changes, lameness, and debility. Congenital or acquired. Uterine malposition, teratogenic insults (arthrogryposis), and genetic defects can cause contracted limbs in newborn foals. Chronic pain (physitis, osteochondrosis, degenerative joint disease, or soft-tissue wounds and infection) is most common cause of acquired tendon contracture. Pain induces the withdrawal reflex, flexors are stronger so horse walks on its toes or knuckles in the fetlocks. Nutritional errors causing osteochondrosis and physitis must be addressed. CS : Foals cannot stand, some attempt to walk on the dorsum of their fetlocks, and others can stand but knuckle in the fetlocks or carpi. One foal may get better other may get worse. Rapid onset in sucklings and weanlings 3-12 mo old, may walk around on their toes with their heels off the ground. A slower onset produces a “boxy” hoof with an elongated heel and concave toe, physitis also is +nt these horses. Both forelimbs involved, worse in one leg. Toe abscesses are a frequent complication.
Older horses (1-2 yr old) knuckle in the metacarpophalangeal joints, which are swollen and enlarged. These horses are upright and straight-legged in both fore- and hindlimbs with flexor tendon and suspensory ligament involvement. Yearlings usually are more severely affected and more difficult to treat than younger animals,
Tx: splints and casts for foals. Nutritional correction, proper hoof trimming and analgesia in early cases in sucklings and weanlings. Inferior check desmotomy most commonly used procedure and does not interfere with future performance. Joint capsule contracture, collateral ligament malformation, and bone involvement are complications in chronic cases. Px ok if dx early.
Fluid therapy- all animals
Vomiting results in loss of H2O, H+, Cl-, Na+, K+, and HCO3-. If vomit is primarily stomach contents, 1o loss is HCl, H2O. Most vomit includes proximal duodenal contents, therefore HCO3- also lost. Conclusion: H2O is consistently lost in vomiting, other electrolytes/acid base are best assayed. Diarrhea results in loss of H2O and electrolytes, resulting in dehydration, electrolyte depletion/imbalance, acid-base imbalance, and shock. Intestinal contents are basically ECF; also can lose large amounts of K+. Fluid losses from diarrhea can be particularly severe in the cow and horse (salmonellosis, neonatal calf diarrhea). The primary acid-base disturbance is metabolic acidosis.
Plasma osmolality - ratio of body solute to body water. Effective circulating volume- Part ECF in the vascular space Depends on SNS, angiotensin II, and renal sodium excretion. Regulates by increasing vasoconstriction, and renal sodium resorption (RATS). Hypovolemia causes activation of RATS. If < 5%, PE is normal. If 5%, dry mm but no panting. If 7%, decreased skin turgor, dry mm, mild tachycardia. If 10%, dec skin turgor, tachycardia, dry mm, dec pulse pressure. If > 12%, marked loss of skin turgor, dry mm, shock. In mild dehydration, s/c route (isotonic fluids, max. 5 to 10 ml/lb at each injection site). Need multiple sites. I/p route is quick, easy but can cause dyspnea. IV route indicated with dehydration < 7%.
Amount of fluid - The deficit volume - only 75% to 80% of the deficit should be replaced during the first 24 hours, as it can worsen dehydration.
Total Deficit Replacement Volume (24 hrs) = Deficit Volume(% dehydration x body weight (lb/kg) x 454/1000 x 0.80) + Maint. Volume
Maintenance volumes 2/3 sensible (urine and feces) and 1/3 insensible (panting or sweating). (30 X BWKg) + 70.
-A 22-lb (10 kg) dog, 7% dehydrated will need - Volume (ml) required = deficit volume + maintenance volume= [0.07 x 22 lb x 454 x 0.80] + [(10 x 30) + 70]=  +  = 930 ml
- Continuing losses during the replacement - estimate the volume of fluid loss and then double this estimate.
- How to know if animal is receiving an inadequate fluid volume- If the animal is losing body weight while being given crystalloid fluids, the animal is likely receiving inadequate volumes of fluid. One group of patients where body weight may fool you is in animals that are third-spacing fluids (peritonitis, pyometritis, pleural effusions). In these animals the animal may still be dehydrated but the body weight may not have changed. Additionally, if renal function is adequate, an animal which is dehydrated will have a urine specific gravity above 1.025.
-Clinical signs of overhydration- increased serous nasal discharge, followed by chemosis, and finally pulmonary congestion will be ausculated before edema ensues. Clinically, pulmonary edema is the terminal event of overhydration! 1. non-respiratory acidosis (HCO3-). may result from: excess ingestion of H+, decreased elimination of H+ (renal), increased production of H+ (anaerobic metabolism), or increased elimination of HCO3- . It is the most common acid-base disturbance in dogs, cats, and horses. 2. non-respiratory alkalosis ( HCO3-) excess ingestion of HCO3-, excess admin. of HCO3-, excess loss of H+ (vomiting), or sequestration of H+ (functional 3rd space loss). This acid-base disturbance is common in the cow (displaced abomasum). 3. respiratory acidosis (CO2) hypoventilation. This is common in the anesthetized horse. 4. respiratory alkalosis (CO2). hyperventilation, pain, excitement, and artificial ventilation that is excessive.
Shock therapy with crystalloid fluid: (no head trauma or pulmonary edema) - Dog – 90 mL/kg/hour. Cat – 60 mL/kg/hour
Blood transfusion (PCV < 20%): 20 ml/kg fresh whole blood. 15-30 ml/kg Oxyglobin.
Shock therapy for head trauma or pulmonary contusions: Hypertonic saline + Hetastarch or dextran. Total dose = 5 ml/kg. Draw up 1/3 volume as 23% saline, 2/3 as colloid.
Small volume resuscitation: 5ml/kg IV hetastarch or dextran. Repeat every 5-10 minutes until HR, pulses and color improves.
Crystalloids - Run very fast. Doesn’t stay in vascular space, so need to give 3-4 times what they have lost. Avoid in animals w/ interstitial edema (head trauma, pulmonary contusions, hypoproteinemia). RL - Buffered pH of about 7.4 which is good for acidosis, The lactate is converted to bicarb for acidosis, Lactate is metbolized in the liver and has calcium. Avoid in cows (alkalosis). Normalsol R - Buffered pH of about 7.4 which is good for acidosis, The acetate in normalsol R is converted to bicarb for acidosis. Acetate is metabolized in the muscle and has magnesium.
0.9% NaCl - Not buffered, so good for alkalosis. Also for hyperkalemia, hypercalcemia.
5% Dextrose in water - Hypotonic solution, Don’t use in shock, Causes lysis of RBCs. Should be used when there is hyperkalemia, hypoglycemia, or as a supplement in maintenance fluid.
0.45% NaCl -Hypotonic solution. Na overload. Don’t use in shock, heart failure, or pulmonary edema. Good for maintenance fluids (Add 20 mEq/L of K+)
Hypertonic saline (7.2%) - Pulls fluid out of interstitial space (7%), Used w/ colloids. less volume, quicker resuscitation. Don’t have to carry as much volume in the large animals (e.g. cow with toxic mastitis). Avoid in small animals.
Colloids- help in retention of fluid in the vascular space. Increases oncotic pressure b/c are not filtered in the glomerulus. Give smaller volume to restore circulation. Indications: Hypoproteinemia, 3rd space loss, Head trauma, pulmonary edema, leaky capillaries, SIRS. Eg. Hetastarch, Dextran 70, Whole blood – if PCV drops below 20% and TP < 3.5 (1 mL of blood per pound will raise hematocrit 1%) then give 20 mL/kg, Oxyglobin – same as above at a rate of 15-30 ml/kg, Whole plasma
- If there is evidence of ongoing blood loss into the abdominal cavity, a snug compressive bandage should be applied, being careful not to impair respiration.
Food allergy (dogs and cats) - Mostly young animals. Non-seasonal pruritus, usually generalized. May mimick atopy and FAD. Papules and erythema, secondary pyoderma, hotspots, hyperpigmentation, and seborrhea, mostly at ears, feet, inguinal, axillae, anterior forelegs, periorbital, and muzzle. In cats may present as pruritus of the head and face, miliary dermatitis, or as eosinophilic granuloma complex. Tx hypoallergenic diet. The most common proven allergens in the cat are fish, beef, chicken.
Foot and Mouth Disease – Vesicular disease. Aphthovirus of picornavirus family. REPORTABLE. Seven serotypes, many strains. Mutate frequently. Extremely contagious disease of cloven-hooved animals. Ruminant, swine. Swine are accelerators of the disease. Camels resistant to natural infection. High morbidity, low mortality.
• Transmission - Contact, aerosolized virus, present in all secretions/excretions, contaminated feed (offal). Ranch contaminated for 1 month, can spread through wind easily. Can live in pharynx for up to 2 years.
• Clinical signs - Lameness, excessive salivation dt ulceration of oral cavity, interdigital space, coronary band, teat and udder. Cardiac muscle necrosis. Long convalescent period.
• Diagnosis - Fluid sample from blister. ELISA.
• Test and slaughter - Huge economic impact. Last case in US in 1929, Canada and Mexico are free. Vax – killed, short duration at best.
Footrot – Fusobacterium necrophorum, Dichelobacter melaninogenicus, Bacteriodes nodosus. Gram- obligate anaerobes, fecal contaminants. The major cause of lameness in beef and dairy cattle. Disease most prevalent during wet or very dry weather. Once skin broken, organisms in soil readily infect wound.
• Clinical findings - Edema and erythema of interdigital region w/ no evidence of foreign body. Severe lameness. Swollen, painful, stinks. Usu unilateral.
• Treatment - Systemic and local antibiotics, clean foot, remove necrotic mass. Response to Abs is fast, if no or little response probably not Footrot.
Fowl cholera (Pasteurellosis) - Pasteurella multocida. Aerosol infection and from blood sucking mites (mechanical vectors) and biting rats. A highly infectious and virulent dz often producing sudden death. High morbidity and mortality. Signs: dyspnea, mucoid oral and nasal discharge, swollen wattles, joint infections, septicemia, diarrhea and tachypnea. Pneumonia is particularly common in turkeys. Hyperemia of abd vessels, stained smear or liver shows bipolar stained rounded end rods. Vax in water but give only in healthy flocks. Tx: Sulfonamides and antibiotics
Fowl pox - Slow-spreading infection. Begins with cutaneous form and goes to diphtheritic form (GI and respiratory). tm by direct contact. Cutaneous – Wartlike nodular lesions on unfeathered skin of chickens and head/upper neck of turkeys. Lesions become yellowish, progress to thick dark scabs, and may coalesce. Low mortality, but decreased production. Diphtheritic – Lesions on mucous membranes of part or entire digestive and respiratory tracts. Caseous patches or proliferative masses. High mortality. Histo - Eosinophilic cytoplasmic inclusion bodies in epithelial cells on microscopy. Infected cells are also enlarged, with associated inflammatory changes. DDx: Infectious laryngotracheitis. vax available
Fracture Classification - Classification by presence of a communicating wound.
• Closed fracture - No wound.
• Open fracture - Grade I has bone fragments penetrating skin from inside to outside. Grade II has soft tissue wound inflicted from the outside. Grade III is a wound from the outside with extensive skin, muscle and bone damage.
• Physeal fractures - Salter I breaks off entire physis, no metaphyseal or epiphyseal involvement. Salter II breaks off entire physis, plus takes a piece of the metaphysis. Salter III breaks off part of physis, up through epiphysis into joint. Salter IV is a longitudinal break through part of metaphysis, through the physis and through the epiphysis. Salter V is a crushing injury which results in premature closure of the growth plate. Salter VI – bridging
Fracture management – all animals
Horses : Fractures of the phalanges and the distal cannon bone - eliminate the bending of the fetlock, by applying a splint with a non elastic adhesive tape. Horse should be walking on its toe. Fractures from the distal cannon bone to the distal radius - Robert-Jones bandage and external splints. The full limb bandage is applied by using many one inch thick layers of padding, each of them covered with elastic gauze. The finished product should be three times larger than the normal leg. The splints should extend from the elbow to the ground and be placed behind and on the outside of the leg. Fractures of the radius - prevent lateral movement of the leg. use full limb Robert-Jones bandage and use lateral splint extending up the side of the chest to the whithers, tapped to the leg as far up as possible. Fractures above the elbow - It is impossible to effectively immobilize those fractures, but because they are well protected by their muscle coverage a stabilization device is not necessary. Fractures from the distal cannon bone to the hock - full limb Robert-Jones. Splints extending from the point of the hock to the ground are placed behind and on the outside of the leg. Fractures of the hock and tibia - They are the most difficult to effectively support because of the angulation of the limb. An outside splint bent to follow the contour of the leg from the hip to the ground is used over a full limb Robert-Jones. Fractures of the femur - do not require immobilization.
Cattle : Fractures of major long bones in adult cattle usually are not treated. Fracture of the tuber coxae occur when cattle are hurried through narrow doorways.
Fractures of the proximal and intermediate phalanges may be considered for tx tractable, young adult cattle. Fracture of the distal phalanx is relatively common in adult cattle. Onset of lameness is rapid, and the pain usually severe. If the medial digit, animal crosses legs. A debilitating arthritis may develop at the fracture site. If tx done, the sound digit should be elevated on a wooden block, and the affected digit immobilized in a flexed position to the block using methyl methacrylate adhesive.
Dogs and cats :
Closed Fractures: skin is not broken. Compound Fractures: the skin is broken, and bone is exposed. Epiphyseal Fractures: commonly seen in young, growing dogs. In < 1 yo, there are soft areas near the ends of each long bone where growth takes place(growth plates or epiphyseal plates). Because these are areas of growth, they are rich in immature non-calcified cells that form a soft, spongy area of the bone. These growth plates are more easily fractured because they are the weakest part of the bone. The distal ends of the femur (thigh bone) and humerus (upper front leg) seem to be particularly susceptible to this fracture. Greenstick Fractures: small cracks within the bone which leave the bone basically intact, but cracked. The bone is not completely broken. The symptoms and risks - Fractures involving a joint are the most serious. A broken back may displace the spinal cord and cause complete paralysis. When a bone within a leg is broken, no weight is placed on the paw. With a sprain or lesser injury, it may use the leg somewhat, but walk with a limp. Management: splints, casts, pins, steel plates, and screws can be used to realign the bone and allow healing. Growing puppies may heal in as little as five weeks, and because of their size they put less weight on the bone. Therefore, a fracture in a young puppy may be treated with a cast but the same fracture may need to be 'pinned' in a geriatric (senior) dog in which healing may take twelve weeks or more. Hairline fractures may only require rest, while surgical intervention will usually be needed in more severe fractures. Right hock fractures are the most common career ending injury of racing greyhounds. Certainly, more toes and metacarpals/metatarsals (“quarter bones") are broken, but their racing careers are more often salvageable. The right hock is usually the one to go, most commonly in the first turn, where the greyhound pushes off with it on the banked curve. All the majority of hock fractures need is 6 - 12 months of house or kennel rest. The reason hocks heal so well is that the usual fracture is a slab fracture of a tiny (<1") bone (central tarsal bone) in a non-moving joint. Fractures of tibia and fibula : Incomplete fractures of the metaphysis and diaphysis of the tibia are common in young growing dogs. Often the presenting signs include lameness although the animal is weight bearing. On physical examination the leg appears to be intact and there is no crepitus evident. There is, however, usually marked exquisite pain over the fracture site. Radiographs in two views will help confirm the dx. Tx is external immobilization.
Complete fractures: Physeal fractures occur in young dogs prior to the closure of these physes. Sometimes minimal open reductions will be necessary if not, small Kirschner wires can also be used to stabilize the bony epiphysis in place over the metaphysis. Proximal tibial physeal fractures, once reduced, can be immobilized adequately in a Schroeder-Thomas splint or lateral coaptation splint. Distal epiphyseal fractures, once reduced, can be easily maintained in reduction with a cranial half cast. Tibial crest avulsions occur commonly and must be treated with open reduction and internal fixation. The method of choice seems to be tension band wiring of the avulsed piece, but care must be taken not to close this physis in very young dogs or cats because of resulting deformity. If such a technique is used in the very young dog, it is necessary to remove the tension band wire within 4 weeks. Older animals may not need to have the devices removed. Salter I breaks off entire physis, no metaphyseal or epiphyseal involvement. Salter II breaks off entire physis, plus takes a piece of the metaphysis. Salter III breaks off part of physis, up through epiphysis into joint. Salter IV is a longitudinal break through part of metaphysis, through the physis and through the epiphysis. Salter V is a crushing injury which results in premature closure of the growth plate. Diaphysial fractures commonly due to vehicular injury. Transverse, short oblique and spinal fractures as well as spiral fractures with butterfly fragments and comminuted fractures are common. Simple fractures, if easily reduced, can be adequately immobilized in a functional below-the-knee cast using the cranial half cast with the caudal element. This cast is especially helpful in severely comminuted fractures in which internal fixation may have considerable shortcomings. Most short oblique or transverse fractures of the tibia can be easily handled through intramedullary pinning. Half-pin or full-pin external skeletal fixation is used for both open and closed fractures of the tibia. Plate and screw fixation is commonly used for tibial fractures. Plates are used to buttress comminuted fractures of the proximal tibial metaphysis, or for any shape of diaphyseal fracture. They are most amenable for use with comminuted fractures. Plates are placed on the cranial-medial surface of the tibia. Proper contouring to the S-shaped surface is necessary. It is important to make all skin incisions over the cranial or cranial-lateral surface of the crus so that they will not lie directly over the plate following fixation.
Growth plate injury Since most of the longitudinal growth of bones occurs up to eight months of age, growth plate injuries that occur after this point are not as devastating. The growth plate is a weak link in the bone construct, therefore it is more susceptible to injury. In pets the age at which the fracture occurs tends to be a significant factor. Common locations Type1 – hip joint (slipped femoral capitis), knee (distal femur) Type 2 – knee (distal femur) Type 3 – elbow (distal humerus) Type 4 – elbow (distal humerus) Type 5 – 1. wrist or carpus (distal ulna or the distal radius less commonly), this results in an angular limb deformity); 2. ankle or hock (distal tibia). Growth plate becomes nonfunctional in many cases and the final length of the bone may be shorter than normal. If the final length of the bone is not 20 to 25% shorter than the normal bone, the pet likely will not have a noticeable gait abnormally when walking or running. A portion of the growth plate may remain functional (open) and thus the bone and limb becomes twisted. In the front limb where the bones are paired (radius and ulna) the limb may become twisted at the wrist (carpus). Surgery done as soon as possible after this type of injury occurs. Generally pins are used to repair these types of fractures if a type 1 or 2 fracture occurs. Type 3 and 4 may need a screw and pin placed. If the joint surface has been directly violated as in a type 3 or 4 fracture the joint should only be immobilized with a bandage or splint/cast for a very short period of time. Prolonged splinting of a limb that has had a repaired joint fracture could lead to permanent stiffness of the joint. The elbow and knee seem to be the most common regions to have problems if immobilized for too long (get scar tissue and joint becomes very stiff).
Fractures of Radius and ulna Fractures may be complete or incomplete and may include one or both bones. The level of the fracture site may be the same in both bones or may be widely separated. Fractures of the distal one-third of the radius and ulna are associated with a higher incidence of delayed union or nonunion, which has been related to the precarious blood supply of this area in small breed dogs. It is these fractures of the radius and ulna that will be the most troublesome. Most animals that have radial and ulnar fractures will present non-weight-bearing on the affected limb, but occasionally animals with greenstick fractures or nondisplaced epiphyseal injuries may present weight-bearing. The smaller the dog, the more difficult it may be to achieve healing, probably as a result of diminished surface contact. Small dogs need good reductions with adequate stability if they are to progress toward satisfactory union. The larger the dog, the less need there is to have a perfect anatomical reduction of the fracture. In dogs over 30 lb, reduction of the shaft to greater than one half the diameter of the bone is usually sufficient to progress to satisfactory union. The stability that can be achieved in larger dogs with this amount of bone contact is usually sufficient to provide adequate callus and union. In small breed dogs this amount of reduction would provide very little stability, which in turn may lead to loss of reduction, with delayed union or nonunion. The closed reduction of closed fractures and immobilization in casts or splints is very useful in treating fractures of the radius and ulna. Most fractures are handled in this manner. The older the dog or the smaller the dog, the greater attention is spent in achieving a form-fitting splint that will impart stability to the fracture site.
Occasionally closed reduction of closed fractures is not possible because of delay in attempting the reduction or because of interposed soft tissue. Sometimes open reduction of closed fractures may be performed without internal fixation, especially in fractures that are relatively transverse.
Femur fractures PROXIMAL FEMORAL FRACTURE OR SUBTROCHANTERIC FRACTURE Following routine fascia lata incision, the biceps femoris should be retracted caudally and the vastus lateralis should be retracted cranially. Further proximal and medial exposure can be obtained by incision of the origin of the vastus lateralis. Very proximal medial exposure may require complete severance of the origin. Proximal caudal exposure is improved by adductor myotomy; however, this should be performed only when necessary. MIDSHAFT FEMORAL EXPOSURE In a routine lateral approach to the femoral shaft, the adductor may be severed where necessary; however, it should always be done minimally. The surgeon should be aware that a significant source of diaphyseal blood comes through the adductor insertion in the immature animal. DISTAL FEMORAL SHAFT Supracondylar fractures are approached adequately through a standard lateral approach to the femoral shaft coupled with a lateral approach to the stifle. This will allow for full visualization of both fracture components. Such an approach requires incision through the fascia lata and appropriate biceps and vastus lateralis retraction. The fascia lata incision is continued distally over the lateral side of the stifle and arthrotomy is performed. The two incisions are then connected to allow for complete medial patellar luxation and quadriceps retraction. Hemorrhage necessitating ligation will occur from branches of the caudal femoral artery.
CLOSED REDUCTION AND EXTERNAL FIXATION Manipulative reduction of this fracture by closed means is not possible. The anatomical location, that is, heavy muscling and proximal medial bony displacement, is responsible for the inability to gain anatomical reduction. External fixation is not an adequate method of treatment for these fractures unless the fracture is incomplete. The only devices that could be useful would be any splint or cast that was made into a spica to completely immobilize the hip region. The device could be plaster, plastic, wood, or a reinforced Robert Jones dressing, as long as a spica was formed. OPEN REDUCTION AND INTERNAL FIXATION Open reduction is accomplished by the proximal surgical approach to the femur. Traction and manipulation are needed to restore alignment. In cases of comminution, especially with loss of a medial buttress, reduction may be accomplished by coaptation of bony fragments to the internal fixative.
Free Gas Bloat – Secondary bloat. Motility disorder, accumulation of gas in rumen, due to physical obstruction (FB, stenosis, stricture). Affects one animal. Often after pneumonia, dt vagal indigestion and diaphragmatic hernia. Also dt reticular wall lesions, anaphylaxis, grain overload and hypocalcemia. Tympanic resonance over left PL fossa (higher pitched ping than frothy bloat). Relieve easily w/ stomach tube. Tx the cause.
Frothy Bloat – Primary bloat. Can cause sudden death. Legumes. Higher the protein content and digestibility, higher the chances of frothy bloat. Affects several animals. May begin within 1 hr on pasture. Ruminal tympany, sudden severe distension, entire abd may appear enlarged. Marked dyspnea. Not easily relieved by stomach tube. Also dt conc, but the pH of feedlot bloat if < 5, can be prevented by adding 10 – 15 % chopped roughage in feed. Anti foaming agents (veg oils, paraffins) to tx and prevent. DOSS, poloxalene and monensin.
Fungal Diseases - Common mycotic diseases that involve the lungs are blastomycosis, histoplasmosis, and coccidioidomycosis. Cryptococcus can also have pulmonary involvement, but the presenting signs reflect nasal infection. Enter respiratory tract via inhalation of fungal spores. Infection may be successfully eliminated w/out clinical signs, may progress to respiratory disease, or may spread systemically. Dogs with histo often present with GI signs. Dogs with coccidiomycosis often present with skeletal signs.
• Blastomycosis - Blastomyces dermatitidis. Large, broad-based, budding yeast w/ capsule wall. Midwest, acid soil near water. 1 causes granulomatous or pyogranulomatous lesions in the lungs. Lesions may occur in skin, eyes, bone and elsewhere. Draining cutaneous tracts, respiratory disease. Chest rads in dogs. Rare in cats. Amphotericin B. Poor px if disseminated.
• Coccidiomycosis - Coccidioides immitis. Dimorphic soil (alkaline) pathogen. Large, round w/ thick basophilic wall. Arid regions of SW USA. Most common in dogs. Chronic respiratory disease. Chronic cough, anorexic, cachexia, lameness, enlgd joints, fever, intermittent diarrhea. Pulmonary nodules and enlgd hilar ln found on thor rads. Positive coccidiodin test indicates exposure. Do NOT culture. Tx w/ Amphothericin B.
• Cryptococcosis – Cryptococcus neoformans. Narrow-based budding yeast w/ thick, clear mucin capsule. Found in soil, pigeon droppings. Cats > dogs. Cat w/ nasal discharge. Clinical features in cats include swelling or draining fistula over facial bone, chronic nasal discharge. Dogs see neurologic signs, granulomatous chorioretinitis. Dx by ID of fungal organism. Cryptococcal capsular antigen test. Tx w/ Amphotericin B or ketoconazole.
• Histoplasmosis - Histoplasma capsulatum. Small intracellular yeast, can be extracellular. Midwest, nitrogen rich organic material (bat poop). 1 infection in lungs, also in GIT. May see in eye and bone. Syndrome includes hepatomegaly, lymphadenopathy, anasarca and emaciation. Tx w/ ketaconazole.
Furosemide – Loop diuretic, potassium wasting. Reduces absorption of electrolytes in ascending loop of Henle, reabsorption of sodium and chloride, excretion of potassium in distal renal tubule. Directly effects electrolyte transport in proximal tubule. No effect of carbonic anhydrase, does not antagonize aldosterone. The diuretic effect takes place within 5 minutes of IV dosing.
Gastric Dilatation Volvulus - EMERGENCY. Initiated by accumulation of gas. Aerophagia is most likely source. Dilatation precedes volvulus. Most common rotation is clockwise (as viewed w/ dog in dorsal recumbency). Displacement of pylorus occurs from R abdominal wall, toward ventral midline, passing over gastric fundus and body to L abdominal wall. Pathophysiologic effects include compression of posterior vena cava and portal vein, resulting in 2 sequestration of blood in splanchnic, renal and posterior muscular capillary beds. Cardiac arrythmias (VPCs, vtach, supravtach) can occur. Endotoxemia dt hepatic perfusion. Hypotension. Organ hypoxia. Focal myocardial ischemia and hypoxia.
• Diagnosis – Large breed, deep chested dog, dry heaving, abdominal pain, arched back. Anterior abdominal distention, tympanic. R lateral abdominal rads. Passing a stomach tube is not a way of def dx.
• Anesthesia - Neuroleptanalgesics and narcotic agents are suitable for both preop sedation and anesthetic induction. Acepromazine and short-acting barbiturates are contraindicated because of hypotensive, arrhythmogenic and respiratory depressant effects. Isoflurane has less CV depression than halo, enflurane or thiobarbiturates.
• Treatment – Shock tx. Dual cephalic catheters w/ shock fluids. Deflate stomach. Surgery to derotate and gastropexy. Antibiotics. Supplement K+ if needed for cardiac abnormalities.
Gastric Outflow Obstruction – 1) Tumor, 2) Mucosal hypertrophy, 3) FB, 4) Pyloric stenosis (young, brachycephalic pup). Dx w/ barium, endoscopy, U/S. If barium in stomach >15 min in cat or >45 min in dog, abnormal. If FB such as bones, do not use tagamet, will dissolution.
Gastric Ulceration/Erosion – Unknown etiology. Caused by stress, NSAIDs, steroids (dex; not pred), mast cell tumor, GIT tumor. Often subclinical or colic or poor performance. See in non-glandular or squamous portion of margo plicatus in adults and glandular portion in foals. No bacterial cause. High risk is stall w/ high carbo diet. Can see melena w/ major blood loss. Amount of blood loss not indicative of size. Tx w/ proton pump blocker (omeprazole) or H2 blockers (ranitidine). Sucralfate for prophylaxis.
Gerbils – Do not grab by tail. Genetic predisposition for epilepsy.
Giardia – Protozoa. ZOONOSIS. Most human infections waterborne. Ingest cysts from contaminated water. Cysts very resistant in environment. Inhabit mucosal surfaces of small intestine. No part of giardia life cycle takes place in LI. Fecal-oral transmission. Prepatent period 5-14 days. Clinical findings may be inapparent or produce chronic diarrhea (cow patty, no blood or mucous). Dx/ trichrome stain or minimum of three ZnSO4 floats, ELISA. Do not use sugar/salt floats, will damage cyst. Can see motile trophozoites in fresh feces wet mount (hot, steaming poop). Tx w/ metronidozole, fenbendazole. No tx 100% effective. Resistance and reinfection easy.
Glaucoma - Increased intraocular pressure damages the retina and optic nerve. Clinical signs include dilated, fixed or sluggish pupil, conjunctival injection, corneal edema, firm globe. May have lens displacement and rupture of Descemet's membrane. Glaucoma is classified as 1 or 2, open angle or closed angle. Tx acute glaucoma as an emergency, IOP can permanently damage eye w/in few days. Treat w/ mannitol, carbonic anhydrase inhibitors, pilocarpine or timolol.
Glomerular Disease – Proteinuria w/ inactive urine sediment. Signs of glomerular disease, nephrotic syndrome - proteinuria, hypoalbuminemia, ascites, hypercholesterolemia. Progressive chronic diz w/ no cure, poor px.
• Glomerulonephritis - Deposition of immune complexes in the glomerular capillary wall. Tx by correcting underlying disease process if present. Use immunosuppressive therapy. Familial in bernese mountain dog and soft coated wheaten terriers.
• Amyloidosis – Extracellular deposit of glycoproteins. Stain distinctly w/ congo red stain. Amyloid is deposited in renal medulla of cats and glomeruli in dogs. In dogs, deposit in glomerulus leads to proteinuria. In cats, in medullary portion so CRF w/ no proteinuria. Familial in abyssinian cats and shar pei dogs.
Gossypol - Toxic component of cottonseed meal. Causes severe myocardial necrosis and lung damage. Pigs are most sensitive. Also reproductive effects including spermatogenesis, irregular cycling, disruption of pregnancy. Hepatotoxicity.
Gout - Deposition of uric acid crystals in and around joints (articular gout - crippling) and on visceral surfaces (visceral gout – birds?). End result of renal failure. Can dx via fluid analysis, see monosodium urate crystals which are needle shaped and birefringent under polarized light. Allopurinal is the traditional treatment, stops additional lesions. Colchicine/probenecid may reverse lesions.
Granulosa Thecal Cell Tumors - Follicular cell tumor. May produce excessive amounts of estrogen, inducing endometrial hyperplasia and signs of hyperestrogenism. Most common in mare and cow. Mare shows masculine behavior (mounting, aggressiveness, vocalization). Dx via rectal exam, check testosterone level in blood. Surgical excision.
Grass Tetany - A metabolic disturbance characterized by hypomagnesemia. Most common in adult cows and ewes in heavy lactation on lush grass pasture. Clinical findings include acute convulsive episodes. In less severe cases, stiff, ill at ease, hypersensitive. Hypomagnesemia, hypocalcemia. Treat with IV calcium and magnesium. Prevent by supplementing magnesium during danger periods.
Griseofulvin – Fungistatic. Disrupts mitotic spindle, arrests metaphase. Only works on dermatophytes (ringworm). See Antifungal section.
Guaifensin - Centrally-acting muscle relaxant. Induces muscle relaxation and restraint as an adjunct to anesthesia for short procedures.
Guinea Pigs –
• Nutrition – Water, PU (120ml/kg); reflux food in spout. Have absolute requirement for vita C, must provide in diet. Cabbage, green peppers. If not, get scurvy, hemorrhage into joints, etc.
• Repro – Gestation 68d. Litters 1-13, 2-4 avg, precocious young (fully haired, eyes open). If not bred by 8 mos, pelvic symphisis fuses resulting in dystocia. Ovarian cysts common, OHE.
• Infectious Diz – Strangles, Staph abscess under jaw. Bordetella bronchiseptica, resp diz w/ hx of contact w/ rabbit.
Gutteral Pouch Empyema - Pus in the guttural pouch. Inspisated pus = chondroids. Usually culture S. zooepidemicus. Develops 2 to upper respiratory infection in horses, can also develop 2 to congenital tympany. Affects horses of any age. See chondroids on rads. Endoscopy. Nonsx if no chondroids, place indwelling cath, flush, lavage. Surg via viborg’s triangle, get chondroids out, leave drainage.
Gutteral Pouch Mycosis - Caused by a fungal infection of the gutteral pouch, usually Aspergillus. Unilateral epistaxis due to fungal erosion of the internal or external carotid. Hemorrhage may be fatal. Treat as an emergency, is life threatening. Clinical signs 2 to damage to cranial nerves and arteries within gutteral pouch mucosa. Dysphagia, Horner's syndrome, laryngeal hemiplegia, dorsal displacement of the soft palate. Endoscopy, check both pouches. Treatment is surgical, hyovertebrotomy. Occlude blood blow on both sides of lesion so no retrograde flow using balloon-tipped catheter. Ddx – ethmoid hematoma.
Gutteral Pouch Tympany - Distention of the guttural pouch with air in young horses (days to 1 y.o). Nonpainful swelling, may cause dyspnea, dysphagia, aspiration. Rads or needle decompression to dx. Sx – viborg’s triangle, excise medial lamina of eustachian tube, fenestrate median septum between pouches. Good px if no aspiration.