Antibiotic resistance genes characterization of non-typhoidal Salmonella serovars of layers

Abstract

This study aimed to detect the presence of antibiotic resistance genes (ARGs) in 23 non-typhoidal Salmonella (NTS) isolated from layer breeds of an organized poultry farm. Phenotypically resistant isolates (including intermediate) for different antibiotics were subjected to PCR for detection of ARGs. Among quinolone-resistant isolates, gyrA, parC and qnrS genes were found in 100%, 95.65% and 4.35%, respectively. Other genes such as β-lactams resistant blaTEM, streptomycin-resistant aadA1 and sulfisoxazole-resistant sul1 were found in 21.74%, 50% and 42.86%, respectively. None of the isolates was found positive for tetracycline-resistant genes screened. Overall, this study detected a few genetic determinants of antibiotic resistance in the isolates that can give rise to the possibility of transmission to the environment or other bacteria. Regular monitoring and surveillance of NTS for various antibiotic resistance genes need to be emphasized to address public health threats.