Study of class 1 and 2 integrons and antimicrobial resistance in Salmonella isolated from broiler chicks in Chaharmahal va Bakhtiari province

Abstract

Background and Aim: High prevalent of drug resistant in Salmonella is a threat to human’s health. Integrons are one of the most important factors that can contribute to the occurrence of MDR bacteria. The aim of this study was to determine the prevalence of class 1, 2 integrons among Salmonella strains isolated from broiler chicks. Materials and Methods: This study was performed on 100 Salmonella isolated strains, collected from broiler chicks samples during the summer of 2015 in Chaharmahal va Bakhtiari. The prevalence of class 1and 2 integrons were verified using specific primers by multiplex PCR assay. Susceptibility to antimicrobial agents was tested using the disk diffusion method according to the CLSI 2011. In the end integrons prevalence and drug resistance were analyzed by using SPSS software. Results: Screening of Salmonella isolates revealed the prevalence of class 1, 2 integrons (50%), (28%) and (48%), respectively. Based on the results of the antibiogram test, the highest rate of antibiotic resistance was Ampicillin among all isolates. The highest rate of antibiotic resistance in samples of IntI 1-positive have been to Gentamycin and Tetracycline (16%) and in IntI 2-positive have been to Gentamycin (35.7%). Also the intermediate resistant strains to Chloramphenicol in the samples of IntI 1-positive were 72% and in the samples of IntI 2-positive were 42.9%. Conclusions: The presence of two classes of integrons and its direct connection with the MDR in Salmonella is concerned. Based on the results of this study, significant correlations were between MDR and integrons that are a serious problem in human and veterinary medicine.

Keywords

• Salmonella
• Integrons
• Drug resistance
• Broiler chicks