Abstract: The aim of this study was to determine the virulence genes, phylogenetic groups and antibiotic susceptibility of Escherichia coli isolated from slaughtered pigs. A total of 77 strains of E. coli were isolated from pig samples collected from pig slaughterhouses in Shaanxi province, Chongqing municipality and Henan province for this study. The results showed that iutA was most frequently detected among the virulence genes tested, and group A was the dominant one. Resistance to tetracycline and trimethoprim/sulfamethizole was detected most frequently among 12 selected antibiotics. Overall, most of the isolates (90.91%) were resistant to 3-9 antibiotics, and even some were resistant to up to 11 antibiotics. Our findings indicate that slaughtered pigs carry multidrug-resistant E. coli strains. These strains are likely to enter into the food chain through the pork production process and cause potential health risks to consumers, highlighting the necessity of strengthening food hygiene supervision.

Key words: slaughtered pigs, Escherichia coli, virulence gene, phylogenetic groups, antibiotic resistance