Submitted to: Food Safety Consortium Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 10/30/2004
Publication Date: 10/3/2004
Citation: Gailey, J., O'Connor, A., McKean, J., Hurd, H.S. 2004. Enumeration of Salmonella in postmortem porcine samples [abstract]. In: Proceedings of the Food Safety Consortium Annual Meeting. The Food Safety Consortium Annual Meeting, October 3-5, 2004, Ames, Iowa. 2004 CDROM.
Technical Abstract: Previous research provides invaluable data about the prevalence of Salmonella in swine (percent of positive pigs) entering the food chain at the abattoir. Much of the recent literature implicates the pre-slaughter holding facilities as a potential source of Salmonella for swine. However, the potential danger posed by the holding pen and the overall risk of Salmonella cannot be adequately evaluated because most previous studies tested only for the presence/absence of Salmonella. A quantitative assessment of the amount of Salmonella in swine tissues at slaughter is necessary to adequately evaluate the Salmonella hazard posed by swine under current processing methods. The purpose of this study was to quantitatively describe the amount of Salmonella in cecal contents, feces and visceral lymph nodes of swine when they enter the abattoir. This study included 210 total animals from three separate Midwest abattoirs. Of these animals 74/210 cecal contents, 18/210 fecal samples, and 23/210 ileocecal lymph nodes were positive for Salmonella. From these positives, 74 were from plant A, 10 from plant B, and 30 from plant C. Thirty-four of the 114 positive samples were below the detectable limit of the MPN test (2-11 cfu/g). The average amount of Salmonella detected in cecal samples was 1.8 log MPN/g (range 0 to 5.0 logs), in fecal samples was 1.9 log MPN/g (range 0 to 4.5 logs) and in ileocecal lymph nodes was 2.9 log MPN/g (range 0 to 5.2 logs). These data show that the majority of Salmonella-positive animals have relatively low levels of Salmonella. However, a small portion of animals tested, especially the lymph node-positive animals, died post a significant hazard. The results from this descriptive study should provide valuable information for conducting a hazard analysis of the pre-harvest portion of the pork production system. Especially important, these data provide the ability to calculate estimates of potential illnesses associated with the production of pork.