Determination of presence of antibiotic resistant extraintestinal pathogenic escherichia coli (Expec) in cattle carcasses and slaughterhouse environment

Aim: In this study, it was aimed to determine ExPEC presence, phylogenetic groups, antimicrobial-resistant phenotypes, and their clonal relatedness in beef cattle and slaughterhouse environment. Materials and Methods: A total of 447 beef cattle samples [rectum (n:133), hides (n: 133), carcass (n:133)], environment samples [paddock (n:12), knife (n:18), water (n:6)], and workers hand samples [(n:12)] were analyzed for the presence of ExPEC using classic microbiological methods and multiplex PCR (papA, papC, iutA, kpsMTII and fimH virulence genes). Phylogenetic groups were tested by triplex PCR (TspE4.C2 clone, chuA and yjaA genes), and clonal relatedness was tested by ERIC-PCR, and screened for antibiotic susceptibility according to the EUCAST standards. Results: 36 (8,80%) out of the 447 samples analyzed were contaminated with ExPEC. Among the 36 ExPEC isolates characterized, four phylogenetic groups were identified including D (14/36, 38,88%), B2 (9/36, 25%), B1 (9/36, 25%) and A (2/36, 5,55%). It was determined that 61,11 % (22/36) of the isolates were resistant to at least two antibiotics and the highest resistance was found against ampicillin with 61,11 %. The ERIC-PCR results showed that proliferated numerous bands (1-5 bands), ranging from 100 to 1500 bp. Moreover, the ERIC-PCR patterns were classified into 19 clusters. Conclusion: The results of this study show that beef cattle and slaughterhouse environments can be a potential contamination source of genetically similar antibiotic-resistant ExPECs. In this context, it will be important to monitor ExPEC regularly in beef cattle, and to deal with it within the framework of One Health approach. Keywords: Beef cattle, Extra-intestinal pathogenic E. coli (ExPEC), slaughterhouse, antimicrobial susceptibility, phylogenetic groups, clonal relatedness