Salmonella-prevalences in Danish organic, free-range, conventional and breeding herds

The results from the Danish serological Salmonella surveillance on meat juice from slaughter pigs in the herd types: conventional herds, organic herds, free-range herds and breeder herds were compared. Seropositive samples were found in all herd types. The relative risk for a sample to be seropositive in free-range herds was 1.7 compared to conventional herds (p=O,OOOI) when confounder control for herd size was applied. An apparent increased risk in organic herds and reduced risk in breeder herds were not statistically significant. The analysis of results from organic herds was based on relatively few samples. Due to the expected increase in number of alternative production systems and difficulties in application of the full panel of recommendations for reduction of the Salmonella infection in these herds, future studies should focus on identification of specific Salmonella risk factors within alternative production systems and develop new tools based on this knowledge