Evaluation of a multiplex PCR method to serotype in animal feeds pre-enrichment broth cultures.

The identification of serotypes remains a highly important public health concern for microbiological analysis of foods, feeds, and clinical samples. Outbreaks of human salmonellosis are sometimes linked to contact with infected animals and animal feeds. To possibly reduce the number of outbreaks, it is important to rapidly, efficiently detect in animal feeds and food products. A multiplex PCR for molecular serotyping of previously used in a single lab validation study for serotyping in multiple human food matrices was used in this investigation to evaluate the effectiveness of the multiplex PCR assay as serotyping method and screening tool for in animal feeds. This approach is unique in that: •The multiplex PCR serotyping assay may be used for rapid screening and serotyping of from contaminated animal feed at the non-selective pre-enrichment step.•The assay may provide the serotype or identification of in positive samples at concentration as low as 10 CFU/25 g after a 24 h non-selective pre-enrichment step.•In addition to the ability to serotype, this assay contains A as an internal control for positive identification. The A shows positive indication for outside of the 30 serotypic banding patterns.