Top 20 Bovine Conditions Part 2

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This 4-part series on the top 20 bovine conditions will set you up for boards success.

5 more of Zuku’s top 20 bovine conditions to know for boards success:

  1. Polioencephalomalacia

                    Head-pressing and proprioceptive deficits in a bull with polioencephalomalacia

    • Classic case: Less than 2-year-old grain-fed cow with:
      • Sudden onset segregation from herd
      • Aimless wandering, recumbent, convulsing, odontoprisis
      • Star-gazing, tetraparesis, hyperesthesia, opisthotonus
      • Blind with normal PLR
    • Dx:
      • Transketolase: measures activity of thiamine pyrophosphate (TPP): high TPP effect is diagnostic
      • Therapeutic response to thiamine within 24 h
      • CSF: Normal to pleiocytosis and increased protein
      • Rule out lead poisoning with whole blood sample
    • Rx:
      • Thiamine, anticonvulsants if needed
      • Prevent in herdmates of affected cow by giving them thiamine
    • Pearls:
      • Occurs with: High rumen thiaminase activity with high-grain diets, raw soybeans in diet, & possibly high dietary sulfur (does not affect thiamine levels but causes polioencephalomalacia)
      • Good prognosis; only die if Rx is delayed or with sulfur toxicity version

  2. Johne’s disease (Mycobacterium avium subsp. paratuberculosis)

                    Typical stage 3 Johne’s

    • Classic case: Most cases are subclinical, but 3 clinical stages of disease:
      • Stage 1: Young asymptomatic, infected; NOT yet shedding and NOT reactive on diagnostic tests
      • Stage 2: Older asymptomatic, infected; shedding and positive on culture and ELISA
      • Stage 3: 3 to 5-year old thin cattle with voluminous diarrhea, decreased milk production, brisket edema, enlarged mesenteric lymph nodes
      • NO loss of conscious proprioception, NO facial paralysis, NO Horner syndrome
    • Dx: None are very sensitive in early disease
      • Individual animal: Fecal culture (gold standard!), PCR, rectal mucosal histopathology
      • Herd-level: Pooled fecal culture, PCR when positive
      • Herd surveillance: Serum or milk ELISA (serum more sensitive, both very specific)
    • Rx: None; euthanize affected cows and REPORT
      • Can improve herds with managerial changes, e.g.: separate manure handling and feeding instruments, do NOT pool colostrum, annual ELISAs, maintain young herd
    • Pearls:
      • Tip of the iceberg – for every stage 3 cow, expect 3–4 x more cows in stage 2 and 10–15 x more cows in stage 1

  3. Abortion

                    Early term fetal abortion with fetus in amnios

    • Classic case: May or may not see fetus but cow no longer pregnant
      • Abortions can be classified loosely as: early, mid-, or late-term (1st, 2nd, or 3rd trimester)
    • Dx: Definitive Dx difficult (only in 30% of cases) due to fetal autolysis, disappearance of toxins, self-correction of physical causes, and abortion often occurs long after infection
      • Specific etiologies may cause abortion at specific stages of gestation, for example:
        • Early (1st half gestation): trichomoniasis, heat
        • Mid: Neosporosis
        • Late: Foothill abortion, brucellosis, leptospirosis, listeriosis, sarcocystosis, mycoplasma/ureaplasma, nitrates, anaplasmosis, Ponderosa pine, Chlamydia
        • Variable: Bovine viral diarrhea virus (BVD), infectious bovine rhinotracheitis (IBR), Campylobacter, Trueperella, prostaglandin shot
      • Fetal or placental tissue analysis: Culture, PCR, immunofluorescence, etc.
      • Dam testing: Serology, PCR, etc.
      • Specific tests depend on DfDx list
    • Rx: None; prevent with…
      • Vaccinate dams against: Leptospirosis, IBR, BVD, brucellosis, Campylobacter fetus
      • Test bulls to prevent trichomoniasis
      • Check feed for nitrates
      • Wait until 3rd trimester to put dams on Foothill Agent-infected pastures
      • Keep dogs off pastures (prevents Neospora caninum)
    • Pearls:
      • Normal abortion rate = 1%; investigate if 3–5%!
      • Develop list of DfDx based on timing (early, mid, or late)
      • Brucellosis and trichomoniasis are REPORTABLE

  4. Calf diarrhea

                    Calf with E. coli diarrhea

    • Classic case: 2–10-day old calf with diarrhea, lethargy, depression, hypothermia, sepsis
    • Dx:
      • Ensure adequate colostrum to calf (normal = refractometer total protein >5.5 gm/dL)
      • Use laboratory values (e.g., blood pH, bicarbonate, base excess, glucose) to optimize fluid therapy for severely dehydrated calves
      • Salmonella spp.: Culture stool at least 5 times
      • Giardia spp. and cryptosporidia: Fecal flotation with direct smear (Giardia) and acid fast stain (crypto) and/or immunoassays
      • BVD: PCR on ear tissue or blood
      • Rotavirus: Fecal Rotazyme test
      • Coronavirus: Fluorescent antibody tests on duodenal jejunal samples
    • Rx:
      • If calf over 5–7% dehydrated & very sick use IVF – determine type based on pH status/base deficit (usually sodium bicarbonate with dextrose)
      • If calf less than 5–7% dehydrated use enteral fluids – electrolyte replacer and milk
      • +/- Antimicrobials and antiinflammatories
      • Prevention: Good calf management – clean calving areas and hutches, provide good quality colostrum (1 gallon colostrum per 100 lb calf in first feed)
    • Pearls:
      • Most outbreaks of diarrhea in calves are caused by a combination of pathogens

  5. Lumpy jaw & wooden tongue
    • Classic case: Any age/breed/use of cow with:
      • Lumpy jaw: Gradual onset of hard, non-movable masses on facial bones (rarely draining) with weight loss and quidding
      • Wooden tongue: Lethargy, ptyalism, protruding tongue, swollen throatlatch, stridor, dysphagia; hard, irregular, firm soft tissues in mouth and pharynx
    • Dx:
      • Etiologies:
        • Lumpy jaw: Actinomyces bovis
        • Wooden tongue: Actinobacillus lignieresii
      • Needle aspirate and gram stain (A. lignieresii = gram - vs. A. bovis = gram + rods)
      • Radiograph jaw
      • Manual pharyngeal exploration unless any neuro signs (don’t get rabies!!)
      • Cranial abdominal ultrasound or radiography
    • Rx: IV sodium iodide
      • Lumpy jaw: Sometimes cull because of prognosis
      • Wooden tongue: Sometimes also penicillin
    • Pearls:
      • Lumpy jaw = hard tissues getting softer; fair prognosis but bony deformation likely to remain
      • Wooden tongue = soft tissue getting harder; excellent prognosis
      • Both conditions can be herd problems

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Paratuberculosis (Johne’s) image courtesy of Dr. Michael Collins, other clinical images courtesy of Dr. Lisle George, James Rickwood (cow eating grass through barbed wire)