Top 20 Bovine Conditions Part 1

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  • Bovine questions make up 13% 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.
  1. Bovine lymphosarcoma
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    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: 25% of cases have peripheral lymphadenopathy; can also see exophthalmos, weight loss
      • Cardiac: 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
      • Gold standard: lymph node biopsy and histopathology confirms lymphosarcoma
      • BLV infection: Positive antibodies ( ELISA most common) to BLV or PCR or antigen-capture ELISA
      • Note: Serologic or virologic positive for BLV does not definitely diagnose lymphosarcoma because prevalence of BLV is high and so few seropositive cases develop lymphosarcoma
    • Tx: NO effective or legal treatment
      • Control: test and cull positive animals greater than 6 months of age in herds with a low BLV prevalence
      • Prevent horizontal spread in herds with high prevalence by changing needles, using rectal sleeves, and good fly prevention
    • Pearls:
      • Grave prognosis for lymphosarcoma
      • Cows w/ lymphosarcoma will not pass slaughter inspection
      • Prevalence of BLV in most U.S dairy herds is high, but most are asymptomatic and their prognosis for life is good
      • Upwards of 30% of infected animals will have persistent lymphocytosis serving as a reservoir for further spread
      • Only approx. 5% of BLV-infected animals get lymphosarcoma

  2. Ketosis
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    Transfaunation
    • Classic case:

      • 3 types – thin cow up to 45 days post-partum (type I), obese cow peri-partum (type II), or 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
      • Subclinical
        • Can be common in dairy herds
        • High blood ketone levels without obvious clinical signs
        • Decreased milk production and reproductive fertility possible
        • Increased risk of metritis, displaced abomasum, early culling from the herd
    • Dx:
      • Measure betahydroxybutyric acid in blood (best), milk, or urine; w/ clinical ketosis is greater than 14.4 mg/dL in whole blood
      • Look for acetoacetic acid in urine with dipstick
    • Tx: Depends on type:
      • Type I – simple and short term Tx: oral propylene glycol, IV dextrose
        • Corticosteroid use is controversial
        • Drives glucose into cells but also quells the immune response
        • Risky in a post-partum animal
      • Type II – difficult and longer-term Tx: transfaunate and pump with liquid nutrition via ororuminal tube, IV dextrose
      • 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; manage dry periods and dry cow nutrition to prevent obese cows, cull
      • Economically important because higher culling rates, more retained placentas, decreased pregnancy rates, and decreased milk production in obese cows

  3. Bovine viral diarrhea (BVD)
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    Ptyalism
    • Classic case:

      • Unvaccinated younger cow with acute diarrhea, nasal discharge, ptyalism, ocular discharge, oral ulcers, fever, anorexia, coronitis (not all will occur)
      • 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
      • Gold standard: virus isolation however PCR on milk, serum, whole blood, tissues or semen is the rapid test of choice
      • Antigen-capture ELISA on blood or tissue
      • Often requires paired serology to definitively diagnose recent infection vs. exposure or vaccination
      • Virus isolation or histopath at necropsy
      • Ear notching for PI cattle (PCR or ELISA): most commonly done on calves
    • Tx:
      • Supportive care for simple adult, unvaccinated cows showing signs of diarrhea, fever and anorexia; prognosis for these animals is good
      • None for calves born with developmental defects or animals with mucosal disease
      • Prevention: Test and remove PI calves; vaccinate
    • Pearls:
      • Grave prognosis except for adult with mild, non-mucosal disease
      • Worldwide, economically important pestivirus
      • Not zoonotic but very contagious

  4. Omphalitis, septicemia, joint ill, meningitis
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    Joint ill - septic metatarsophalangeal joint
    • Classic case:

      • Omphalitis: fever with swollen, painful umbilicus and patent urachus +/- GI pain with secondary peritonitis
      • Septicemia: calf less than 2 weeks old with fever, diarrhea, depression, systemic compromise
      • Joint ill: lameness with painful, swollen, hot 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
    • Tx: antimicrobials 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 and 4 L colostrum by 4 hours of age; clean calving environment
    • Pearls:
      • Prognosis variable: good for omphalitis, poor for others
      • Measure total protein at 24 hours’ age: adequate colostral transfer if greater than 5.5 g/dL

  5. Traumatic reticuloperitonitis
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    Papple shape
    • Classic case:
      • 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
      • Sloshing fluid sound left thoracic cavity in severe cases with pericarditis
      • Rare in pre-ruminating heifers
    • Dx:
      • Positive withers grunt test: pinch withers while listening for a vocalization with stethoscope
      • Look for pain response while balloting left ventral abdomen
      • Abdominocentesis: purulent or serosanguineous fluid
      • Cranial abdominal ultrasound or radiography
    • Tx: Similar outcomes with medical and surgical, better prognosis if treated early
      • Medical: magnet, laxatives, antimicrobials, analgesics
      • Surgical: rumenotomy, antimicrobials, magnet
      • Prevention: ONE magnet per cow given at 400-600 pounds weight can prevent
    • Pearls:
      • 75% survival; bad outcome with secondary vagal indigestion, diffuse peritonitis, and pericardial involvement

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Images courtesy of Dr. Lisle George and The Yorck Project (3000-year old image of a farmer plowing with cattle, Egypt)

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