Molecular Survey of Quinolone Resistance in Salmonella spp. Isolated From Poultry Products in Karaj, Iran

Background: Nontyphoidal salmonellae and serovars of Escherichia coli, Listeria, Shigella, and Campylobacter are among the most important foodborne bacterial agents. Objective: The aim of the present study was molecular detection of quinolone resistance in Salmonella spp. isolated from poultry products in Karaj, Iran, using polymerase chain reaction (PCR). Materials and Methods: Ninety samples of poultry products were collected from different brands and markets during SeptemberDecember 2017. All samples were enriched in nutrient broth and Selenite F broth, and salmonellae were isolated by xylose lysine deoxycholate agar. The presence of specific genes of qnrA, qnrB, and qnrS was investigated employing PCR technique and subsequently, specific primers. Results: None of the 30 egg yolk samples had bacterial growth in the culture medium. In total, 29 (48.33%) out of 60 raw chicken meat samples were determined to be contaminated with Salmonella using culturebased methods (i.e., 7 (35%) out of 20 drumstick, 15 (62.5%) out of 24 breast, and 7 (43.75%) out of 16 liver samples). In addition, the frequency of qnrA, qnrB, and qnrS genes in the samples was 10.34%, 68.96%, and 86.20%, respectively. Conclusion: The results of this study showed a high frequency of Salmonella contamination and qnr genes in the contaminated samples.