A serological Survey of B rucella spp., S almonella spp., T oxoplasma gondii and T richinella spp. in Iberian Fattening Pigs Reared in Free‐Range Systems

Summary Zoonotic agents such as B rucella spp., S almonella spp., T oxoplasma gondii and T richinella spp., all considered high‐risk zoonotic pathogens by the E uropean F ood S afety A gency ( EFSA ), may cause no symptoms of infection in free‐range pigs yet still have a significant public health impact. A serological survey was therefore performed to determine the history of occurrence of these pathogens in such pigs in southern S pain. A total of 709 serum samples were collected at abattoir from pigs from 79 farms and analysed for specific antibodies against the above pathogens using commercially available ELISA kits. Encysted T richinella spp. larvae were also sought following the artificial digestion method of diaphragm pillar muscle. The results showed S almonella spp. to be widely distributed among the sampled herds [73.42%, 95% confidence interval ( CI 95 ) 65.6–81.78] and T oxoplasma gondii to be present in over half (58.23%, CI 95 47.33–69.07). The seroprevalence of B rucella spp. was very low (3.8%, CI 95 0.18–7.42), and antibodies against T richinella spp. were not detected. No encysted T richinella spp. larvae were microscopically detected.