Occurrence of anti Sarcocystis spp., anti Toxoplasma gondii, and anti Neospora spp. antibodies in equines from western Santa Catarina, Brazil

Equine raising is generally articulated as a secondary activity on farms, where animals are used for leisure or work. Thus, it is important to consider the health of these animals, seeking to understand which are the main agents that circulate in a given farm or region. In this sense, this study aimed to evaluate the presence of IgG anti-Sarcocystis spp., anti-Toxoplasma gondii, and anti-Neospora spp. antibodies in equines in western Santa Catarina, Brazil. A total of 100 serum samples from horses from 10 farms, located in the municipalities of Faxinal dos Guedes, Xaxim, and Xanxerê were analyzed from June to December 2019. The samples were evaluated by indirect immunofluorescence reaction (IIFR) to detect antibodies of IgG class against the three agents. The results showed that the equines in the region are seropositive against the three studied agents, 11% of which for Sarcocystis spp. 21% for T. gondii, and 20% for Neospora spp. The analysis of the presence of these protozoa in different environments showed that both stabled and extensively raised horses presented signs of contact with the studied agents. Animals that live only in stables had a higher occurrence of IgG anti-Sarcocystis (7/32; 21.88%) and anti-T. gondii (11/32; 34.38%) antibodies. The evaluating of animals raised on pasture, semi-extensively and extensively, showed a higher percentage of seropositivity for N. caninum (9/34; 26.47%). The high occurrence of animals seropositive to the studied protozoa reinforces the importance of controlling and preventing these agents in the region, as they have the potential to cause a high impact on equid farming, mainly involving reproductive losses and equine protozoal myeloencephalitis (EPM).