Association of origin, performance, and health metrics of beef-on-dairy feedyard cattle with liver abscess at harvest

Lay Summary Beef-on-dairy (BxD) cattle have higher frequency of liver abscesses (LA) at harvest than native beef breeds and Holsteins, though cause of increased LA remains unclear. We evaluated associations between origin, performance, and health metrics with LA at harvest in BxD cattle. Feedyard data and liver scores were collected from two sources (Dataset 1, n = 330 cohorts; Dataset 2, n = 386 cohorts). For Dataset 1, livers were scored using Elanco’s liver scoring system with 4 outcomes of interest: Total LA (All scores; D1TA), Severe LA (Scores A+, A+Adhered, A+Open; D1SA), Severe+ LA (A+Adhered and A+Open; D1S+A), and Severe as proportion of Total LA (D1ST). For Dataset 2, livers were scored in 3 non-mutually exclusive categories: Abscessed (D2TA), Condemned (D2CL), and Adhered (D2AdL). Multiple risk factors such as sex, days on feed, average shipping weight, percentage of cohort railed, and origin were associated with D1TA, D1SA, D1S+A, and D1ST. Average daily gain (ADG) and quarter harvested were associated with D2TA and D2CL. Average shipping weight and origin were also associated with D2TA. The only risk factor associated with D2AdL was sex. These results identify factors associated with LA in BxD cattle; further research is needed to determine management strategies to mitigate LA occurrence.