Prevalence of and risk factors for antimicrobial-resistant fecal bacteria in beef cow-calf operations: A systematic review

Ahmad Ali; Thomas Denagamage; Jorge A Hernandez; João H J Bittar; Alice C Y Lee; Kwang C Jeong; Subhashinie Kariyawasam

doi:10.1016/j.rvsc.2025.105761

Prevalence of and risk factors for antimicrobial-resistant fecal bacteria in beef cow-calf operations: A systematic review

Res Vet Sci. 2025 Sep:193:105761. doi: 10.1016/j.rvsc.2025.105761. Epub 2025 Jun 10.

Authors

Ahmad Ali¹, Thomas Denagamage², Jorge A Hernandez², João H J Bittar², Alice C Y Lee¹, Kwang C Jeong³, Subhashinie Kariyawasam⁴

Affiliations

¹ Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA.
² Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA.
³ Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611, USA.
⁴ Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA. Electronic address: skariyawasam@ufl.edu.

PMID: 40544561
DOI: 10.1016/j.rvsc.2025.105761

Abstract

Objectives: This systematic review aims to estimate the prevalence of and risk factors for antimicrobial-resistant fecal bacteria (ARFB) in beef cow-calf operations.

Methods: Inclusion criteria determined for prevalence studies were condition (ARFB), context (cow-calf operations), and population (beef cattle in cow-calf operations). Inclusion criteria determined for risk factors were population (beef cattle in cow-calf operations), exposure (antimicrobial use, management practices), and outcome (ARFB). Peer-reviewed publications were identified in Agricola, Embase, PubMed, and Web of Science databases. A critical appraisal and certainty assessment of all selected studies was conducted for prevalence and cross-sectional studies separately. The results of this systematic review were synthesized narratively.

Results: A total of 13 cross-sectional studies published from 2000 to 2024 were included in the data extraction, critical appraisal, and synthesis. The prevalence of ARFB varied between 0.1 % and 100 % against different antimicrobials at the isolate, animal, and herd levels. In final multivariable analysis, the use of antimicrobials (OR = 5.80-7.10), farm size (OR = 5.75), age of animal (OR = 2.33-10.0), health status (OR = 4.30), season (OR = 4.36-9.60), herds with calf mortality (OR = 6.40) and location of farms (OR = 2.80) were potential risk factors associated with ARFB in beef cow-calf operations.

Conclusion: The results are inconsistent due to the heterogeneity in the study populations, study designs, outcome measures, and study risk of bias. The overall certainty of evidence is from low to high. However, the high prevalence of ARFB poses a risk that could potentially be transferred to the next level of beef production. The results of this systematic review will inform beef producers reagrding their management practices.

Keywords: Antimicrobial resistance; Beef cow-calf operations; Enteric fecal bacteria; Prevalence; Risk factors.

Publication types

Systematic Review

MeSH terms

Animal Husbandry
Animals
Anti-Bacterial Agents* / pharmacology
Bacteria* / drug effects
Cattle
Cattle Diseases* / epidemiology
Cattle Diseases* / microbiology
Drug Resistance, Bacterial*
Feces* / microbiology
Prevalence
Risk Factors

Substances

Anti-Bacterial Agents