DNA microarray for tracing Salmonella in the feed chain.

In the present study we investigated if the microarray platforms Premi®Test Salmonella (PTS) and Salmonella array (SA) could be applied for the identification and typing of Salmonella in artificially contaminated animal feed materials. The results were compared to the culture-based MSRV method and serotyping according to Kauffman-White. The SA platform showed a specificity of 100% for the identification of Salmonella compared to 93% with the PTS platform and a sensitivity of 99% or 100%, respectively. Among all identified Salmonella serotypes, 56% with the SA platform and 81% with the PTS platform were correctly identified. The difference in probe signal intensity for each probe was higher between duplicates analyzed with the SA platform than with the PTS platform. Attempts to use the microarray platforms from BPW resulted in many false negative samples and incorrect typing results. The microarray platforms tested were simple to use and might have a potential in tracing studies for Salmonella in the feed chain particularly when rapid information about serotypes are important.