Molecular detection and antibiotic resistance profile of Escherichia coli and closely related Enterobacteriaceae from cattle carcasses and meat contact surfaces at slaughterhouses in Abuja, Nigeria.

Abstract

Escherichia coli contaminations of edible animal products reflects hygiene failures along the slaughter and processing value chains and represent a significant public health concern, particularly when isolates harbour antimicrobial resistance genes (ARGs). This study assessed the prevalence, antimicrobial resistance (AMR) patterns, and ARG profiles of presumptive E. coli recovered from cattle carcasses and meat-contact surfaces in a government-owned (Gwagwalada) and a privately-owned (Dei-Dei) slaughterhouse in Abuja, Nigeria. Swab samples from carcasses (n = 300) and meat-contact surfaces (n = 240) were processed using standard microbiological methods, and antimicrobial susceptibility testing was performed by the disk diffusion method. A subset of isolates was randomly selected for molecular confirmation, while multidrug-resistant isolates were screened for selected ARGs by PCR. The overall prevalence of presumptive E. coli across both slaughterhouses was 19.4%. All isolates exhibited multidrug resistance, with universal resistance to ampicillin and high resistance to other commonly used antimicrobials. Multiple antibiotic resistance indices indicated exposure to high-risk contamination environments. Molecular analysis revealed frequent detection of clinically important ARGs, including tetA, blaCTX-M, blaTEM, and blaVIM. These findings indicate substantial contamination of slaughterhouse environments with multidrug-resistant E. coli and underscore the need for improved hygiene practices, prudent antimicrobial use, and strengthened molecular surveillance to limit the dissemination of antimicrobial resistance along the human food chain.