Location: Livestock Issues Research
Project Number: 3096-32000-009-039-T
Project Type: Trust Fund Cooperative Agreement
Start Date: Sep 1, 2024
End Date: Dec 31, 2025
Objective:
The objective of this proposal is to evaluate fecal and environmental prevalence of pathogens associated with liver abscesses. Concurrently, this research will evaluate antimicrobial resistance patterns between environmental, fecal and liver abscess samples.
Approach:
Steers (n=120; 500-600 lbs.) will be sourced from local auction markets and processed at a research feedlot. Steers will be assigned to either a negative control treatment or a treatment in which the steer is administered injectable metaphylactic antimicrobial. Every 60 days, fecal and pen surface samples will be collected and evaluated for the presence and concentration of Fusobacterium and Salmonella. Two isolates from each culture will be collected and subjected to antimicrobial resistance profiling. Upon harvest, livers and liver abscess material will be collected and subjected to the same bacteriological and resistance profiling analyses. Post hoc, data will be stratified into steers with and without liver abscesses, and pre-harvest microbiological data will be regressed to determine if prevalence or resistance patterns are predictive of liver abscess presence at harvest.
