Serological survey on Sarcoptes scabiei var. suis in fattening pigs and sows from intensive farms in Italy

Sarcoptic mange is the clinical disease caused by the burrowing mite Sarcoptes scabiei, an obligate ectoparasitic arthropod responsible for significant morbidity in both domestic and wild animals. The aim of the study was to investigate the serological prevalence of S. scabiei var. suis in pigs raised in the intensive system in Lombardy region, one of the most suitable regions in northern Italy for intensive pig farming, and to assess the influence of variables related to farm management on the exposure to mite infestation. 219 fattening pigs and 151 sows from 23 conventional farms in Lombardy were sampled; data on farm management were collected, and a biosecurity score was determined for each farm. Blood samples were analysed using a commercial indirect ELISA Kit; generalized linear models were developed to determine the influence of production category and sanitary score on the parasite infestation. At the farm level, 65.2% (15/23) of the selected farms were positive, i.e. 90.9% of those housing sows and 40% fattening pigs. At the individual level, 43 animals (43/370, Prevalence (P%) = 11.6%) were positive to S. scabiei antibodies with higher seroprevalence values in sows (35/151, P = 23.2%) if compared to fattening pigs (8/219, P = 3.6%). A higher seroprevalence was recorded in farms with poor or moderate scores (P = 100% and P = 64.3%, respectively) if compared to those with higher sanitary score (P = 44.4%). Statistical analysis revealed that production category and biosecurity score were significantly associated with the mite infestation. Sarcoptic mange can lead to significant economic losses in pig farming; besides, the zoonotic risk for human infestation due to handling of pig or carcasses should be considered.