Isolation and Identification of Salmonella Typhimurium in Retail Meat Sources by Multiplex Polymerase Chain Reaction

Background: Salmonella enterica serovar Typhimurium is considered one of the most important emerging food-borne pathogens in public health worldwide. Meat is commonly known as the food sources responsible for the salmonellosis outbreak. Methods: Overall, 141 different meat samples were randomly collected from local markets. The conventional culture method was performed to isolate Salmonella spp., and then, using two pairs of primers, a multiplex polymerase chain reaction (PCR) assay was employed to confirm the identification of isolated colonies as Salmonella spp. and determine serovars as Typhimurium. Results: Out of 141 samples, 48 (34%) ones were presumptively isolated as Salmonella on the Salmonella agar medium and distributed as 24%, 23%, and 42% among veal, lamb, and chicken meat, respectively. However, the results of multiplex PCR showed that 4.9% of chicken meat was merely identified as S. Typhimurium. In general, S. Typhimurium isolates were found only in chicken meat. Conclusion: Salmonella Typhimurium isolates were only observed in the chicken meat. Multiplex PCR was found to be a specific and rapid alternative method for the identification of various types of Salmonella.