Extended-spectrum β-lactamases among cloacal Escherichia coli isolates in healthy broilers in Turkey

The aim of this study was to determine the prevalence and clonal typing of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in healthy broilers in Turkey. Three hundred broiler cloacal samples were collected from various broiler slaughterhouses and inoculated on Levine agar plates supplemented with 2 μg/mL cefotaxime. Suspected strains were identified using a BBL Crystal Enteric/Nonfermenter ID Kit (Becton Dickinson, USA) and ESBL production was confirmed using an ESBL phenotypic confirmatory test. ESBL types were analyzed using PCR and sequencing. Pulsed field gel electrophoresis (PFGE) was performed with XbaI for the clonal typing of ESBL-producing E. coli isolates. While 33 phenotypic ESBL-producing E. coli isolates were identified, eight of them had only the blaTEM-1. Twenty-five ESBL-producing isolates were detected. This research is the first on the investigation and detection of ESBL-producing E. coli isolates from broilers in Turkey. In this study, 8.3% ESBL-producing E. coli were isolated from the cloacal samples of broilers collected from slaughterhouses in Turkey. CTX-M-15 (80%) was the most frequently isolated ESBL type. Using PFGE analysis, it was determined that these isolates had clonal similarity.