Study of the frequency of Salmonella Enteritidis tetA, tetB, tetC, cat3 and floR genes in traditional cheeses and its relationship with multidrug resistance

Salmonella is a member of Enterobacteriaceae. Dairy products, such as cheese, are one of the environmental sources of these bacteria. This study was performed to isolate Salmonella enteritidis collected from traditional cheese produced in Chaharmahal va Bakhtiari province, and also to study the frequency of associated gene with drug resistance.
In this cross-sectional study, 100 samples of traditional cheese were collected from Chaharmahal va Bakhtiari province. Bacterial culture and biochemical tests were used to isolate and identify Salmonella strains. PCR assay was used for final diagnosis of Salmonella genus and direct detection of S. Enteritidis, and also to study the frequency of tetA, tetB, tetC, cat3 and floR genes. The Kirby-Bauer disk diffusion method was used to perform the antibiogram tests.
Overall, 32 (32%) cases out of 100 samples were detected as Salmonella contamination. Of these, 10% (31/25 cases) of samples belonged to S. enteritidis. The highest frequency of antibiotic gene resistant belonged to tetC (70%). The highest antibiotic resistance (100%) was related to tetracycline and the highest sensitivity (100%) was related to cefotaxime.
The results of present study showed that S. enteritidis carry high frequencies of antibiotic resistance genes. The presence of high resistance to chloramphenicol and tetracycline can be because of the presence of these genes.