Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: 10/14/2001
Publication Date: N/A
Technical Abstract: Transportation and long-term (> 12 h) holding prior to slaughter of swine have been associated with an increase in Salmonella prevalence at the packing plant. This increase in prevalence has been attributed to the effects of stress on immunity, increased mingling of animals, and reoccurrence of shedding. Little mention has been made regarding the environment as a source of Salmonella infection. The objective of this study was to evaluate the possibility of swine becoming infected with Salmonella typhimurium, in a 2-3 hour intervals, from an environment contaminated with feces. This environment was designed to simulate the holding time prior to slaughter. Forty crossbred market weight swine (~ 92 kg) were exposed to marked strain of Salmonella typhimurium in simulated holding conditions. The contaminated feces were deposited on the floor by swine that had been intranasally inoculated 4 days previously. Exposed pigs were autopsied at 2, 3, and 6 hours after exposure to the contaminated floor. Within 2 hours, 80 percent (8/10) of exposed animals were positive for the marked Salmonella typhimurium strain. At 3 hours after exposure, 60% (6/10) of animals were positive on at least one sample cultured at autopsy. After 6 hours, 100% (5/5) of animals had at least one sample test positive. This study shows that market swine can become infected with Salmonella in the short waiting time before slaughter. Intervention at this step in the pork production process may have a significant impact on the safety of pork products.