Plasmid mediated quinolone resistance determinant qnr B and qnr S in Escherichia coliisolated from poultry colibacillosis

Introduction and Objectives: Colibacillosis is one of the most important bacterial infections in poultry industry that causes high economic losses annualy in the world wild. Quinolones are the potent antibiotic agents used in the prophylaxis and treatment of infections caused by E. coli. Due to the widespread use of these drugs, frequency of resistant to these antibiotics is steadily increasing. Given the fact that food chain is an important route of transferring antibiotic resistance to human, the presence of resistance strains in poultry flocks is a serious threat for public health. Materias and Methods: The aim of this study was to investigate the quinolone resistance of 100 Escherichia coli recovered from broilers referred to the Faculty of Veterinary Medicine hospital in Semnan University. Antimicrobial susceptibility of E. coli isolates were determined by disk diffusion method and the presence of plasmid mediated quinolone resistance determinant qnr B and qnr S were detected using PCR-specific primers. Results: The highest phenotypic resistance was observed for Nalidixic acid (46%), Ciprofloxacin (30%), Levofloxacin (25%) and Ofloxacin (20%) respectively. Also13% and 7% of the isolates harbored qnr B, and qnr S genes. Conclusion: The results of this study indicate that plasmid mediated qnr genes has observed in poultry farm in Semnan, and the use of appropriate therapeutic approaches and the rational administration of antibiotics to control the resistance to these drugs should be considered.

کلیدواژه ها:

Escherichia coli ، Colibacillosis ، quinolone resistance