Document Type : Full paper (Original article)
Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
Background: Extended spectrum beta-lactamase (ESBL) producing Escherichia coli have been reported in humans and animals and induced a main concern in antibiotic resistance in serious bacterial infections. Aims: The aim of this study was to investigate the frequency of ESBL producing E. coli (EPE) strains in turkey meat and intestinal contents and also to compare the antibiotic resistance profile in EPE and non-EPE strains. Methods: Totally; 70 and 110 E. coli strains were isolated from turkey meat and turkey intestinal content samples and after determination of EPE strains by double disc resistance examination; 20 and 22 EPE strains were identified in turkey meat and turkey intestinal content samples; respectively. Then; the antibiotic susceptibility to antibiotics were examined using disc diffusion method. E. coli isolates were further characterized for virulence genes (stx-1 and stx-2) and ESBL genes (TEM; SHV and CTX-M). Results: The E. coli strains not harbored stx genes. The EPE strains in comparison with non-EPE strains were significantly more resistant to ciprofloxacin (47.6 vs 26.5%); tetracycline (80.9 vs 67.3%); ampicillin (47.6 vs 22.4%); penicillin (23.8 vs 10.2%); ceftazidime (47.6 vs 8.2%); ceftriaxone (38.1 vs 18.4%) and cefotaxime (47.6 vs 8.2%). The majority of EPE strains carried the CTX-M gene. SHV has lowest frequency and in EPE strains isolated from intestinal contents was not detect. In this study; 75% of TEM producing E. coli strains and 33% of SHV producing E. coli strains were resistant to ampicillin. In addition; 41.7% of TEM producing E. coli strains were resistant to penicillin and 76.9% of CTX strains producing E. coli were resistant to cefotaxime. Also; in 4.7% of EPE strains isolated from turkey meat observed the imipenem resistance. Conclusion: The appearance of cefotaxime and imipenem resistance in EPE strains induces a concern in growing of antibiotic resistance against broad spectrum antibiotic in E. coli strains.