ARS | Publication request: Salmonella enterica prevalence and serotype distribution in swine at slaughter

Submitted to: International Symposium on Epidemiology and Control of Salmonella in Pork
Publication Type: Proceedings
Publication Acceptance Date: May 1, 2007
Publication Date: May 9, 2007
Citation: Rostagno, M.H., Hurd, H.S., Mckean, J.D. 2007. Salmonella enterica prevalence and serotype distribution in swine at slaughter. International Symposium on Epidemiology and Control of Salmonella in Pork. p. 153-155.

Technical Abstract: The objective of this cross-sectional study was to analyze data available from multiple studies conducted by our research team estimating the prevalence of S. enterica, and the serotype distribution in swine at slaughter, based on different sample types. A total of 1,110 pigs from three large capacity abattoirs located in the Midwestern U.S. were individually sampled at slaughter. Individually paired samples collected included: cecal contents and ileocecal lymph nodes. Samples were collected on multiple occasions in all three abattoirs, transported to the laboratory, and processed for the isolation and identification of S. enterica. The overall prevalence of S. enterica, based on cecal contents, mesenteric lymph nodes, and any of the samples (i.e., cecal contents and/or mesenteric lymph nodes) was 54.7%, 27.9%, and 62.6%, respectively. There was a significant difference (P<0.05) between prevalence estimates based on cecal contents and mesenteric lymph node samples in all three abattoirs, and overall. A variety of S. enterica serotypes was isolated in all abattoirs. The average number of serotypes isolated per group was 3.48. This study confirms that the S. enterica prevalence at slaughter in swine is high, requiring attention due to the associated risk of contamination of the abattoir environment. Moreover, our results demonstrate the common occurrence of a high diversity of serotypes in swine at slaughter. This study also shows that both cecal contents and mesenteric lymph nodes should be considered for a better estimate of S. enterica prevalence at slaughter.