Campus Units

Animal Science, Veterinary Diagnostic and Production Animal Medicine

Document Type


Publication Version

Accepted Manuscript

Publication Date


Journal or Book Title

Microbial Drug Resistance




Antimicrobial resistance in Salmonella from food animals is recognized as a major problem worldwide. Monitoring animals destined for slaughter for antimicrobial resistance that could potentially enter the food chain poses a challenge and abattoirs therefore might be a potential candidate checkpoint for monitoring antimicrobial resistance patterns on farms. A complicating factor however is the impact of lairage on Salmonella detected in pigs at slaughter. The aim of this study was to compare antimicrobial resistance (AMR) patterns in Salmonella spp. collected from swine postslaughter (cecal samples) and upon arrival (fecal samples) at the abattoir to evaluate the feasibility of using slaughterhouse samples for surveillance of prevailing AMR Salmonella on the farm. Eighty-fourSalmonella isolates were recovered from a large, Midwestern US abattoir between September and November, 2013. All isolates were tested for phenotypic antimicrobial resistance to 12 antimicrobials using the broth microdilution assay (NARMS). Whole-genome sequencing was used to identify the AMR genes harbored by the strains. Significant differences were observed between the phenotypes of the isolates, and their genotypes but no significant difference between the genotypic resistance patterns was found. The results indicated that the AMR profiles of Salmonella spp. post-slaughter cannot be predicted from the pre-slaughter samples obtained at the abattoir. Further research that considers the genetic diversity of tested isolates and the test power for genotypic statistical analysis needs to be conducted in order to improve the performance of WGS-inferred antimicrobial susceptibility.


This is a manuscript of an article published as Feng, Qi, Timothy Frana, Catherine M. Logue, James D. McKean, Scott H. Hurd, Annette M. O'Connor, James S. Dickson, Shanyuan Zhu, and Ganwu Li. "Comparison of Antimicrobial Resistance Profiles in Salmonella spp. from Swine Upon Arrival and Postslaughter at the Abattoir." Microbial Drug Resistance (2021). Final publication is available from Mary Ann Liebert, Inc., publishers Posted with permission.

Copyright Owner

Mary Ann Liebert, Inc., publishers



File Format


Available for download on Friday, February 04, 2022

Published Version