Multiplex PCR (mPCR) for the Detection of Salmonella spp. and the Differentiation of the Typhimurium and Enteritidis Serovars in Chicken Meat

Salmonella enterica subspecies enterica serovars Enteritidis and Typhimurium are important causes of foodborne illness. Methods for simultaneous detection of these serovars may contribute for the adoption of measures to prevent these diseases. The polymerase chain reaction to detect individually or simultaneously the serovars Enteritidis and Typhimurium in foods have been standardized; however, the majority of assays employ the fliC gene as a target for detection of serovar Typhimurium. The detection of these sorovars in a few hours allows the food supply chain to take appropriate measures to prevent the distribution of contaminated food. The aim of this study was to develop a new multiplex PCR (mPCR) for the simultaneous detection and differentiation of Salmonella spp., S.Enteritidis and S.Typhimurium in chicken meat. The mPCR assays showed high specificity and differentiated S.Typhimurium from 22 Salmonella serovars tested, including S. Kentucky, showing that it's an alternative to reduce the time required to obtain presumptive positive results. Practical Applications The fliC gene used as target for the detection of serovar Typhimurium is questionable as it has also been described for S. Kentucky. The amplification of STM4492 gene in this study, instead of fliC gene, exhibited high specificity to detect S.Typhimurium. The developed mPCR is an efficient means for the simultaneous detection and differentiation of Salmonella spp., S.Enteritidis and S.Typhimurium in chicken meat after 24h of enrichment. The mPCR has the potential to be used in routine diagnostic laboratories to obtain presumptive positive results and for identification of Enteritidis and Typhimurium strains isolated by the conventional method.