Characterization of Salmonella Gene Expression Profiles When Present in Cattle Subiliac Lymph Nodes-Proof of Concept

<p>Cattle are a noted reservoir for the foodborne pathogen Salmonella enterica, and ground beef has been
identified as a possible mode of transmission for outbreaks of salmonellosis. Surveys of Salmonella
contamination present in ground beef indicate that prevalence is generally low, and that when
isolated the most commonly observed serotypes are Montevideo and Anatum. However, outbreaks
attributed to ground beef are more often the result of contamination with Salmonella Newport or
Typhimurium and rarely attributed to the more commonly observed serotypes. With the potential
for impending regulation on the presence of particular Salmonella serovars contaminating meat, it is
becoming more likely that beef processors will need tools for rapidly identifying certain Salmonella
serotypes when detected. </p>

<p>The stated objectives for this work were to examine the differences in gene content and determine genetic markers (single nucleotide polymorphisms or SNPs) for the differentiation of serotypes more likely to be found in
ground beef, namely Montevideo and Anatum, from those more likely to cause disease when
present, namely Newport and Typhimurium.</p>