NAVLE Food Animal: High-Yield Topics for Bovine, Ovine, Caprine, and Porcine

Food animal questions — covering bovine, ovine and caprine, and porcine — represent approximately 18–23% of the NAVLE combined. Students from companion-animal-heavy programs often have the widest performance gaps in these species, making food animal one of the highest-return areas to invest prep time. This guide covers the must-know topics for all food animal species.

Bovine — High-Yield Topics

Metabolic Diseases of Dairy Cattle

These conditions appear repeatedly on the NAVLE and are heavily interconnected:

• Milk fever (hypocalcemia/parturient paresis): Most common in high-producing dairy cows, periparturient. Decreased Ca ? recumbency, bloat, decreased rumen motility. Stages: Stage I (sternal, hyperexcitable) ? Stage II (lateral, muscle weakness) ? Stage III (coma). Treatment: IV calcium gluconate (slow infusion — cardiac monitoring required). Prevention: low-DCAD diet prepartum, vitamin D administration.
• Grass tetany (hypomagnesemia): Rapidly growing lush pasture ? low Mg absorption. Acute neurological signs (convulsions, death). Treatment: IV MgSO4. Prevention: Mg supplementation.
• Ketosis: Energy deficit in early lactation ? mobilization of fat ? hepatic ketone production. Clinical signs: decreased appetite, low milk production, sweet smell to breath. Diagnosis: serum BHB >3.0 mmol/L. Treatment: IV dextrose, propylene glycol, glucocorticoids.
• Left Displaced Abomasum (LDA): Abomasum shifts from ventral midline to left side. Associated with ketosis and periparturient period. Ping heard over left thorax on simultaneous percussion/auscultation. Treatment: roll and toggle, right paramedian abomasopexy, left flank omentopexy. Right displaced abomasum (RDA) is less common but more dangerous — can volvulize.
• Hardware disease (traumatic reticulopericarditis): Ingested metallic foreign body penetrates reticulum. Clinical signs: decreased appetite, grunting on deep palpation, reluctance to move downhill. Treatment: magnet administration (prevention and treatment), rumenotomy. Pericarditis if the foreign body reaches pericardium — grave prognosis.

Bovine Reproductive Emergencies

• Dystocia: Normal presentation is anterior longitudinal, dorsosacral. Common malpresentations: head deviation (dog sitting position), retained limb, posterior presentation. Management: lubrication, correction of malpresentation, traction, caesarean section if not correctable.
• Uterine prolapse: Occurs within hours of calving. Emergency — replace immediately. Clean uterus, reduce edema (hypertonic solution), push uterus back through birth canal, epidural. Retained placenta often present.
• Retained fetal membranes: Normal expulsion within 12 hours. >12–24 hours = retained. Do not manually remove forcibly (vascular trauma). Oxytocin, broad-spectrum antibiotics. Monitor for metritis and ketosis.
• Metritis: Uterine infection post-calving. Foul-smelling discharge, fever, depression, decreased production. Treatment: intrauterine infusion + systemic antibiotics (ceftiofur).

Bovine Respiratory Disease Complex (BRDC)

Most economically important cattle disease. Multifactorial: stress (transport, weaning) + viral pathogens (BRSV, BHV-1/IBR, BVD, PI3) ? secondary bacterial infection (Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Mycoplasma bovis). Clinical signs: nasal/ocular discharge, fever >104°F, depression, tachypnea. Treatment: florfenicol, tulathromycin, enrofloxacin. Metaphylaxis in high-risk groups.