Effect of pig production system and transport on the potential pathogen transfer risk into the food chain from Salmonella shed in pig faeces

Summary

The prevalence of faecal Salmonella shedding has been compared in organic, conventional outdoor, and indoor finishing pig herds in a Danish survey with participation of 34 herds. Individual faecal and meat juice samples were collected from 30-50 pigs per herd and analysed for presence of Salmonella, and Salmonella antibodies, respectively. The results showed a low level of on-farm Salmonella shedding (<0,2 %) in organic and conventional outdoor herds compared to 2,5 % in indoor pigs (P<0,0001), and also a lower prevalence of Salmonella shedding in outdoor systems at slaughter (<2 %) compared to 4,1 % in indoor systems (P<0,01). The overall seroprevalence was 8,5 % with no significant differences between systems. Seropositivity was a significant predictor of Salmonella shedding at slaughter in individual pigs from conventional systems, but not in organic pigs. The duration of transport did not affect the risk of Salmonella shedding at slaughter.