Mississippi State University
Brandi B. Karisch
Joshua G. Maples
Amelia R. Woolums
Date of Degree
Original embargo terms
Visible to MSU only for 1 year
Graduate Thesis - Campus Access Only
Master of Science
College of Agriculture and Life Sciences
Department of Animal and Dairy Sciences
The objectives of this study were to evaluate the effect of number of stocker cattle in receiving pens (large: n=150 cattle; small: n=50 cattle) on 1) BRD morbidity/mortality, and performance, 2) antimicrobial use and prevalence of antimicrobial resistance in Mannheimia haemolytica, and 3) profitability of stocker operations. No differences were found for morbidity (p=0.5041). Mortality tended (p=0.0744) to be higher in large groups. BW increased (p<0.0001) over time. A treatment*day interaction (p=0.00592) was found for ADG, with largest gains for both groups from day 14-28. M. haemolytica recovery decreased (p=0.0002) over time. Antimicrobial resistance (p=0.0179) and MDR (p=0.0405) were higher in the small group. Treatment costs were higher in the small group ($1,093.53/hd) compared to large ($1,037.04/hd). Because of the nature of a pilot study, further research are needed to determine the effectiveness of reducing animals in a pen on health, growth, AMR, and profitability associated with stocker cattle.
MULTISTATE PROJECT NUMBER W2010 CRIS PROJECT NUMBER MIS-331500 DEPARTMENT ORG 011300
Midkiff, Kirsten, "Pen size and BRD: Impacts on antimicrobial use, antimicrobial resistance, performance, and profitability" (2021). Theses and Dissertations. 5233.