Student Case Presentation
Acute Mortality Event in Cow-Calf Herd
| Date/Time: |
9/11/2025 #3
|
| Presenter: |
Antonio A. Silva |
| Veterinary School: |
TAM |
Abstract:
5 cattle experienced sudden deaths with no apparent signs of illness. 3 cattle were 6–9-year-old cows at one location, the 2 others were heifers less than 2 years old at another location. Calves were vaccinated once at branding with a clostridial vaccine, dewormed with pour-on moxidectin every 6 months. Cattle have access to 200+ acres with 2 large tanks, and a creek. Upon physical exam of the herd, body conditions were acceptable (average 5/9). Several cows had long rough haircoats, and some haircoats of black cattle had a red tinge. The initial differential diagnoses included, liver flukes, clostridial infection, toxic exposure, and trace mineral aberration. Trace mineral analyses were performed on 14 members of the herd, results were within normal ranges, apart from molybdenum which was deficient. The clients were instructed to submit cattle within 24 hours of their death to the diagnostic laboratory for necropsy, add albendazole to the deworming protocol to treat any liver fluke infections, vaccinate against clostridial diseases, leptospirosis, and vibriosis, and booster vaccines in 4 weeks. One heifer did have an abortion due to an administration of albendazole during early pregnancy. Between 14 to 16 days from the initial consultation 2 recently dead heifers were submitted for necropsy. The necropsy report for both heifers identified liver fluke tracks, and hemorrhagic enterocolitis. Clostridial fluorescent antibody tests revealed both heifers were positive for Clostridium novyi/haemolyticum. The final diagnosis was clostridial hemoglobinuria by way of fascioliasis. Continued care recommendations were to vaccinate against clostridial diseases every 6 months and institute comprehensive parasite management. The importance of clostridial vaccinations and fascioliasis cannot be overlooked due to their constant presence in the environment and devastating impact on herd health.
