Bovine questions make up 15% of the NAVLE® so it’s well worth spending some quality time learning the major diseases.
This 4-part series on the top 20 bovine conditions will set you up for NAVLE® success.
5 of Zuku’s top 20 bovine conditions to know for NAVLE® success:
- Bovine lymphosarcoma
Submandibular lymphadenopathy- Classic case:
- Central nervous system - paraplegia, tetraplegia, paraparesis, tetraparesis; head tilt, facial paralysis, dysphagia
- Gastrointestinal system - free gas bloat, vagal indigestion, palpably enlarged abdominal lymph nodes, melena, thickened rectum
- Lymph nodes - lymphadenopathy, exophthalmos, weight loss
- Heart - unexpected and sudden collapse, death, congestive heart failure, jugular pulse, distended jugular or mammary veins, arrhythmia, tachycardia, weak pulse, subcutaneous edema
- Dx:
- Etiology: Bovine leukemia virus (BLV), an oncogenic retrovirus
- Lymph node biopsy
- Positive antibodies (AGID or ELISA) to BLV
- PCR or antigen-capture ELISA for BLV
- Rx: NO effective or legal treatment; D-penicillamine has been given to affected pregnant cattle to save a valuable calf but questionable
- Pearls:
- Grave prognosis
- Affected cows will not pass slaughter inspection
- Cows with BLV – most are asymptomatic, 5-10% get lymphosarcoma, and 30% have persistent lymphocytosis
- Classic case:
- Ketosis
Transfaunation- Classic case:
- 3 types – thin cow up to 45 days post-partum (type I), obese cow peri-partum (type II), too much silage at any stage of lactation (silage type)
- Dairy cow 1-4 weeks post-partum with mild anorexia, low milk production, malodorous breath
- Pica or paresthesia, aggressive behavior
- Mild proprioceptive deficits with hepatic failure
- Dx:
- Measure betahydroxybutyric acid in blood (best), milk, or urine; diagnostic is greater than 14.4 mg/dL in whole blood
- Look for acetoacetic acid in urine with dipstick
- Thorough dental examination
- Rx: Depends on type:
- Type I – simple and short term Rx: oral propylene glycol, IV dextrose, corticosteroids, oral potassium and calcium salts
- Type II – difficult and longer-term Rx: transfaunate and force-feed, IV dextrose, oral potassium and calcium salts, insulin
- Silage type – don’t feed silage with high concentrations of butyric acid to pre- and post-fresh cows!
- Pearls:
- Type I – excellent prognosis; prevent with low protein diet, maximize energy in early lactation, and monensin
- Type II – poor prognosis; cull obese cows
- Economically important because higher culling rates, more retained placentas & decreased pregnancy rates and milk production in obese cows
- Classic case:
- Bovine viral diarrhea (BVD)
Ptyalism
- Classic case:
- Unvaccinated younger cow with acute diarrhea, nasal discharge, ptyalism, ocular discharge, oral ulcers, fever, anorexia, coronitis
- In-utero infection: early embryonic death, cerebellar hypoplasia, developmental defects, abortion
- Persistent infection (PI): If a cow becomes infected by a NON-cytopathic strain of virus between 40-120 days gestation, or calf is from a PI dam, the calf will be PI and act as a reservoir; if infected by cytopathic strain later in life, cow gets mucosal disease
- Mucosal disease: acute signs and fatal with 2-4 weeks
- Dx:
- Etiology: Bovine viral diarrhea virus, a Pestivirus
- PCR on milk
- Antigen-capture ELISA on blood or tissue
- Virus isolation or histopath at necropsy
- Ear notching for PI cattle: use PCR or ELISA
- Rx:
- None
- Prevention: Test and remove PI calves; vaccinate
- Pearls:
- Grave prognosis except for subclinical disease in adult vaccinated cow
- Worldwide, economically important pestivirus
- Not zoonotic but very contagious
- Classic case:
- Omphalitis, septicemia, joint ill,
meningitis
Joint
ill
- septic metatarsophalangeal joint- Classic case:
- Omphalitis – fever with swollen, painful umbilicus and patent urachus +/- GI pain with 2º peritonitis
- Septicemia – calf less than 2 weeks old with fever, diarrhea, depression, systemic compromise
- Joint ill – lameness with painful, swollen joint
- Meningitis – opisthotonus, hyperesthesia
- Dx:
- Omphalitis – palpate and ultrasound umbilical structures
- Joint ill – ultrasound/radiograph affected joint, aspirate and culture joint fluid
- Meningitis – CSF aspirate shows increased WBC count and protein
- Rx: Antibiotics and…
- Omphalitis: Surgical removal for advanced cases
- Joint ill: Lavage joint then instill antibiotics; analgesics/NSAIDs
- Meningitis and septicemia: Systemic supportive care, NSAIDs, diazepam if seizures
- Prevention: Make sure calves get a minimum 500 grams IgG on first feeding and 4 L colostrum by 2 hours of age; clean calving environment
- Pearls:
- Prognosis variable – good for omphalitis, poor for others (though some joints better than others)
- Measure total protein at 24 hours’ age – adequate colostral transfer if greater than 5.5 g/dL
- Classic case:
- Traumatic
reticuloperitonitis
Papple
shape- Classic case: Cow over 2 months of age with:
- Acute anorexia and agalactia, unwillingness to move or lie down, arched back, fever, positive grunt test
- +/- Papple shape (pear on right and apple on left) and scant feces if secondary vagal indigestion
- Dx:
- Positive withers grunt test – pinch withers while listening for a vocalization with stethoscope
- Positive abdominal rebound test – percuss abdomen while looking for splinting and violent responses
- Abdominocentesis – purulent or serosanguineous fluid
- Cranial abdominal ultrasound or radiography
- Rx: Similar outcomes with medical and
surgical,
better prognosis if treated early
- Medical – magnet, laxatives, antibiotics, analgesics
- Surgical – rumenotomy, antibiotics, magnet
- Prevention: ONE magnet per cow given at 400-600 pounds weight prevents almost all cases!
- Pearls:
- 75% survival; bad outcome with secondary vagal indigestion, diffuse peritonitis, and pericardial involvement
- Classic case: Cow over 2 months of age with:
Images courtesy of Dr. Lisle George and The Yorck Project (3000-year old image of a farmer plowing with cattle, Egypt)