Gross necropsy, histopathology, and ancillary test results from neonatal beef calves submitted to a veterinary...

The objective of this study was to evaluate the prevalence of abnormal findings in gross necropsy, histopathology, and ancillary test results from neonatal beef calves submitted to a veterinary diagnostic laboratory.

This retrospective clinical case study was conducted by reviewing necropsy reports submitted between 2015 to 2020. Case inclusion criteria were animals had to be a bovine, 2 to 21 days of age, and a nondairy breed.

Gross necropsy, histopathology, and laboratory test results were recorded. Identified lesions and abnormal test results were categorized based on body systems and infectious agent type. Age and system affected were analyzed using a 1-way ANOVA and Bonferonni pairwise comparisons.

Overall, 1,060 reports were reviewed and 95 met the inclusion criteria. Median age of enrolled calves was 9 days (range, 2 to 21). A total of 252 lesions were identified with a median of 3 lesions/calf (range, 0 to 7) and 2 different body systems involved/calf (range, 0 to 5). The most common disorders were classified as digestive (42.1% [106/252]), respiratory (12.7% [32/252]), and multisystemic (11.1% [28/252]). With respect to age and system affected, calves with neurologic lesions were significantly younger (mean age, 5.1 days) than calves with digestive lesions (mean age 9.6 days).

These data suggest a high prevalence of infectious diseases, mainly digestive, respiratory and multisystemic in origin. These findings could help guide producers and veterinarians when assessing factors contributing to neonatal beef calf loss.