HANDLING AND TRANSPORT STRESS INTERACTIONS WITH PATHOGEN BIOLOGY IN SWINE AND CATTLE
Location: Livestock Behavior Research
Title: Does Pre-Slaughter Stress Affect Pork Safety?
Submitted to: Pig Veterinary Society International Congress Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: March 30, 2010
Publication Date: July 18, 2011
Citation: Rostagno, M.H., Eicher, S.D., Lay Jr, D.C. 2010. Does Pre-Slaughter Stress Affect Pork Safety [abstract]?. In: Proceedings of the 21st International Pig Veterinary Society (IPVS)Congress, July 18-21, 2010, Vancouver, Canada. p. 176.
Although much of the Salmonella contamination of pork occurs along the slaughter and processing line, infected pigs delivered to the abattoirs are considered as the original source of pork contaminations. Studies of the effects of pre-slaughter stressors on food safety risk in market pigs are scarce. Therefore, two experiments were designed to determine if common stressors occurring prior to slaughter affect the prevalence and levels of Salmonella in market weight pigs, and consequently, the associated pork safety risk. Initially, a field study was conducted to determine the effect of transportation from the production farm to the abattoir, and pre-slaughter lairage on the frequency of Salmonella shedding in market pigs. A follow up study was conducted under controlled conditions, with the objective of determining if feed withdrawal and transportation affect the levels of Salmonella in the intestinal tract of market-weight pigs. In the first study, significant increase (P<0.05) of Salmonella shedding prevalence was observed from pre-transport (11.3%) to post-transport (20%), and from post-transport to post-lairage (42%). In the second study, feed withdrawal by itself or combined with transportation caused increased levels of Salmonella in the ileum of market-weight pigs (P<0.05), whereas only the combination of feed withdrawal and transportation caused increased levels of Salmonella in the cecum of market-weight pigs (P<0.05). Taken together, our studies show that a significant increase of Salmonella shedding and its levels in the intestinal tract occurs between the production farms and the abattoirs, showing that the process of moving market pigs from the farm to the abattoir contributes to increased pork safety risk. Although many can argue that transporting pigs from the farms to the abattoir is a process that cannot be avoided, it is important to keep our minds open to potential changes or modifications. For instance, transportation conditions can be easily manipulated to minimize stress, and/or the gastrointestinal microbial ecosystem can be made more resilient to changes (or stabilized) through the use of probiotics, prebiotics or other alternatives.