Salmonella infection risk associated with outdoor organic pig production

Summary

For organic pig production little information is available about potential food safety problems with respect to zoonotic bacteria like salmonella. The aim of the current study was to examine the salmonella infection dynamics in organic pigs through an outdoor experimental set-up. Pigs inoculated with Salmonella Typhimurium were grouped with non-infected tracerpigs to determine the transmission of salmonella between animals. The results indicated that the organic pigs were perceptive to infections but that the susceptibility varied considerably between pigs. Furthermore, bacteriological examinations of soil and water samples from the pasture environment showed the ability of salmonella to survive in the non-host environment. Moreover, introduction of salmonella-free pigs into such naturally contaminated pastures caused salmonella-infections in some of the pigs, but mainly where the infection rate had been high previously. Elimination of salmonella-infected animals at an early stage would minimize the build up of high contamination levels and this could probably help to control the spread and persistence of salmonella in outdoor pigs.