53 Investigating the relationship between hoof and heart abnormalities in fed cattle at slaughter.

Abstract More than 25 million fed cattle are slaughtered each year in the United States. Animal welfare issues associated with hoof abnormalities and congestive heart failure (CHF) have increased, with minimal evaluation of the root cause and methods of mitigation for these issues. Both disorders are deleterious to animal health, welfare, and carcass quality. Our objective was to determine the prevalence of hoof abnormalities and CHF within various physical characteristics. To meet this objective, scorecards for each condition were developed based on existing literature and images from the source population of animals. Scores were recorded at a slaughter establishment in the western region of the United States (elevation: 1,417 m) on cattle < 30 mos of age (N = 398). Statistical analysis was performed to determine the prevalence of each disorder. Further analysis was completed to evaluate the differences between the prevalence of carcass characteristics (USDA quality grade (QG), USDA yield grade (YG), hot carcass weight (HCW), ribeye area (REA), and fat thickness (FT)) within each hoof abnormality or CHF score, as well as the differences between each CHF score within each hoof abnormality. Eighty-five percent of cattle had at least one hoof abnormality, 52% had CHF, and 43% had both. We did not find differences (P > 0.1463) in REA, FT, QG, YG, sex, and hide color across hoof scores. Cattle with a wide toe and inward curved hoof had lighter (P > 0.0258) carcasses (421.62 ± 11.26 kg) than cattle with only an inward curve (460.95 ± 2.92 kg). Cattle with mild CHF had heavier (P = 0.0295) HCW (463.60 ± 3.24 kg) than cattle with no CHF (451.51 ± 3.22 kg). REA for cattle with no CHF was 103.17 ± 0.93 cm2, mild CHF was 104.51 ± 0.88 cm2, and severe CHF was 98.63 ± 2.46 cm2 (P = 0.0711). There were no differences (P > 0.1846) in FT or QG between CHF scores. There was a greater proportion (P = 0.0099) of heifers without CHF (70.97 ± 8.17%) than steers (45.78 ± 2.61%). There was no difference (P > 0.4955) between the presence of CHF within each hoof score. Over half of the cattle in this study had hoof abnormalities, CHF, or both. Data suggested there are developing relationships between CHF score and carcass characteristics including HCW and sex. Further research is required to guide actions to address the animal welfare and productivity concerns associated with these issues.