Antibodies anti-Toxoplasma gondii and anti-Neospora caninum in backyard pigs from the state of Mato Grosso, Brazil.

To estimate the seroprevalence of Toxoplasma gondii and Neospora caninum, using an indirect immunofluorescent assay (IFA), and identify the risk factors associated, serum samples were collected from 1,070 pigs from 320 backyard pig farming in the of Mato Grosso state. The animal-level seroprevalence of T. gondii and N. caninum was 32.48% and 13.49%, respectively, with a herd seroprevalence of 55.63% for T. gondii and 27.81% for N. caninum. Feeding the animals with leftovers increases the probability of the presence of anti-T. gondii antibodies in pigs by 1.09-fold. Unlike to T. gondii, feeding with leftovers was found to be negatively associated with N. caninum seropositivity in farm-level analysis and in the animal-level model, so decreasing the chances of positivity. Yet, age was considered a risk factor for N. caninum seropositivity. Further studies are necessary to evaluate the impact of T. gondii infection on backyard pig farming production, and its importance as a source of toxoplasmosis infection in humans in the Mato Grosso state, as well as, the role of domestic pigs in the epidemiology of neosporosis.