Grad Student Competition
Understanding metaphylaxis practices for cattle at uncertain risk for bovine respiratory disease across U.S. feedlots: a survey of veterinary consultants and feedlot managers
| Date/Time: |
9/12/2025
10:45
|
| Author: |
Vanessa Horton |
| Clinic: |
Kansas State University |
| City, State, ZIP: |
Manhattan, KS 66503 |
V. Horton, DVM, MS
1
;
C. Hanthorn, DVM, MS
;
A. Thackrah, MPH
;
D. Renter, DVM, PhD
;
N. Cernicchiaro, DVM, PhD, MS
;
1Center for Outcomes Research and Epidemiology, Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas, 66503
Introduction:
Bovine respiratory disease (BRD) is the most significant disease affecting feedlot cattle in the United States (U.S.). Metaphylaxis, the targeted administration of antimicrobials to high-risk populations, has proven to effectively reduce morbidity and mortality; however, concerns about antimicrobial resistance warrant its judicious use. The decision of whether to use metaphylaxis in cattle at risk for BRD poses a particular challenge when disease risk classification and cost-benefits are uncertain. Our objective was to collect and analyze qualitative and quantitative data used by veterinarians and feedlot managers across the U.S. when determining metaphylaxis use for cattle cohorts at uncertain risk of developing BRD.
Materials and methods:
Data were collected through questionnaires tailored to feedlot managers or veterinary practitioners who assisted U.S. feedlots in metaphylaxis decisions during 2023. Descriptive statistics were performed to summarize responses on the criteria utilized to classify BRD risk (including by whom and when), to inform metaphylaxis use, and to identify areas with information gaps regarding metaphylaxis administration for cattle at uncertain risk for BRD.
Results:
A total of 25 veterinary practitioners, consulting for 617 feedlots (ranging from 80 to 120,000 animal-capacity) across 32 states, and 30 managers overseeing feedlots across 12 states with an average capacity of 28,495 animals, participated in the study. For cattle at uncertain risk of developing BRD, nearly half of veterinarians (48%) expected morbidity between 15 and 20% and mortality between 2 and 3%, whereas only 15% of feedlot managers shared this expectation. Among feedlot managers, the expected morbidity and mortality varied greatly, with 55% expecting morbidities between 5 and 15%, and no clear expected range by a majority for mortality (i.e., responses were well distributed among proposed mortality ranges). Before cattle arrival, veterinarians (73%) and feedlot managers (82%) identified “market channel” as the most influential factor in determining metaphylaxis use. After arrival, “overall cattle health condition” was most frequently reported as highly impactful for the metaphylaxis decision by veterinarians (69%) and managers (75%). Most veterinarians (61%) recommended that feedlot managers should make the final decision on metaphylaxis use, aligning with reports from managers (82%) that the final decision is often made by the feedlot or cattle manager. Veterinarians most commonly reported cattle history (i.e., vaccines, backgrounding, weaning; 64%) in-weight (59%), degree of commingling (50%), distance traveled (50%), and weather conditions (50%) as the primary criteria used to classify cattle at uncertain risk for BRD. Managers cited similar factors, including cattle history (62%) and distance traveled (35%), but most frequently reported source (e.g., sale barn; 45%) and cattle origin (i.e., region; 35%) as the primary criteria, with weather (14%) and in-weight (28%) mentioned less often compared to veterinarians.
Significance:
No major discrepancies emerged between veterinarians and managers in metaphylaxis decision-making for cattle at uncertain BRD risk, indicating these findings are a valuable insight into current industry practices. By enhancing knowledge and identifying information gaps, this study supports antimicrobial stewardship and sustainability in the U.S. beef industry.
