Detection and differentiation of Enteritidis and Typhimurium by multiplex quantitative PCR from different poultry matrices.

1. The aim of this study was to develop a multiplex quantitative polymerase chain reaction (qPCR) based molecular diagnostic kit for rapid diagnosis of serovar Enteritidis and serovar Typhimurium serotypes, which are frequently isolated worldwide from poultry samples.2. Detection and discrimination of Enteritidis and Typhimurium were performed by targeting the and the STM4492 (putative cytoplasmic protein) gene, respectively. The (invasion protein) gene was used to detect spp. as a target gene, since it is considered a standard. In this study, a total of 200 bacterial strains (178 . strains and 22 other genera) were used to test the specificity and sensitivity of the developed kit. The limit of detection (LOD) of the assays was determined to be 10-10 cfu/25 g from chicken meat samples artificially contaminated by litter and 10-10 cfu/ml for cloacal swab samples.3. The multiplex qPCR results were 100% compatible with conventional serotyping results while the specificity and sensitivity values were 100%. These findings indicated that the newly developed multiplex qPCR technique can provide an alternative method to conventional serotyping of Enteritidis and Typhimurium in laboratories lacking adequate infrastructure.