Risk factors associated with Salmonella prevalence in breeding & fattening and in only-fattening herds

The aim of this study is to assess the risk factors linked to salmonella prevalence of slaughter pigs, both in breeding-fattening and in only-fattening herds.Sow batch mixing in farrowing stage and failure in all in - all out practice in fattening rooms are associated with higher seroprevalence as far as the lack in quarantine of gilt acclimatization to the herd microbiological digestive status or absence of antiparasite protocol.Two identified risk factors are associated to hygiene level in farrowing rooms: diarrhea occurrence and a non systematic antibiotic treatment on young piglets. On the opposite, high hygienic quality of water and the strict observance of cleaning and disinfecting protocol (ie systematically disinfecting and observing a sufficient break duration between two subsequent batches in post-weaning rooms; using automatic soaking and detergent in fattening rooms) are linked to lower prevalence levels. The number of fattening pigs per pen is also associated with positive salmonella status.