Investigation of avian pathogenic E.coli strains in chicken carcasses

Avian Pathogenic Escherichia coli (APEC) causes serious infections, especially colibacillosis in poultry, and causes high mortality and morbidity rates and financial losses in poultry farms. Although studies have demonstrated the prevalence of APEC in diseased/dead chickens on farms, the prevalence of APEC in commercial chickens remains a subject of research. The aim of this study was to investigate the presence of APEC in chicken carcasses marketed in markets and butchers in Kütahya by molecular methods and to observe the antimicrobial resistance profile and biofilm capacity. During the study, 36 (83.72%) E. coli were isolated from 43 chicken carcass samples. A total of 20 isolates (55.56%) were identified as APEC by the pentaplex PCR method, based on the presence of five virulence genes (iroN, ompT, hlyF, iss, and iutA) associated with APEC.It was found that 65% of the isolates were susceptible to gentamicin, 60% to trimethoprim-sulfamethoxazole, whereas 85% were resistant to ampicillin and nalidixic acid, 75% to ciprofloxacin and 70% to tetracycline. 80% of APECs were found to be multidrug resistant. The effect of glucose on biofilm formation in APEC isolates was evaluated; while 40% of APEC in LB medium were identified as biofilm producers, this rate increased to 55% with the addition of 0.5% glucose concentration. This study presents data on APEC presence, antibiotic resistance, and biofilm capacity in Kütahya marketed chicken carcasses.