A Rapid Identification of Salmonella enterica in Chicken Skin Using an invA Molecular Marker

Salmonella is a gram-negative bacillus that lives in the intestinal tract of human and animals and causes diarrhea. Salmonella could be found in undercooked products of poultry with no impact on the taste, smell, or appearance. Since poultry eggs and meat might be sources of Salmonella and pose a hazard to public health, it is important to accurately detect Salmonella infection. In this regard, the present study aimed to develop a rapid and sensitive method for the diagnosis of Salmonella spp. in samples from the poultry industry. To do so, the sensitivity of S. enterica serotype Enteritidis detection was assessed with ten-fold serial dilutions in peptone water to give suspensions containing ۱۰۰ to ۱۰۵ CFU/mL. For artificial inoculation, skin samples were sequentially inoculated with the serial dilutions, while a control sample was included to ensure that the skin was not naturally contaminated with Salmonella. ۵۳ commercial chicken skin samples were obtained from different local shops. Then, DNA was extracted from all samples, and the quality of extracted DNAs was checked by spectrophotometry and confirmed by agarose gel electrophoresis. For PCR, a pair of oligonucleotide primers, INVA, was designed to amplify the invA gene. Results revealed a band of ۷۹۶ bp in samples artificially contaminated with S. Enteritidis. Likewise, the ۷۹۶ bp band was detected in ۳۸ samples (۷۱%) with deferent intensities, which presented different amounts of contamination. Accordingly, the present study provided a valuable method for the detection and control of Salmonella infection in the poultry industry, since results would be available in less time than with the conventional cultural method.

کلیدواژه ها:

Salmonella enterica ، invA gene ، PCR assay ، Public Health