Prevalence of Sarcocystis neurona and Neospora spp. infection in horses from Brazil based on presence of serum antibodies to parasite surface antigen.

This study investigated the prevalence of Sarcocystis neurona and Neospora spp. infection in horses in Brazil by testing for specific antibodies in their blood. The research found a high prevalence of S. neurona and a low prevalence of Neospora spp.

Research Methodology

• The researchers collected blood samples from 961 horses in Brazil as part of their research to determine the seroprevalence of Sarcocystis neurona and Neospora hughesi infections.
• To identify the presence of these infections, the researchers tested the horses’ sera for the presence of antibodies against the major surface antigens SnSAG4 and NhSAG1. These antigens, present on the surface of the parasites, trigger an immune response in the host, resulting in the production of specific antibodies.

Key Findings

• The researchers found that 669 of the 961 horses (about 69.6%) tested positive for antibodies against SnSAG4, suggesting a high prevalence of Sarcocystis neurona infection in these horses.
• Contrastingly, only 24 of the 961 horses (roughly 2.5%) tested positive for antibodies against NhSAG1, indicating that Neospora hughesi infection is relatively uncommon in horses in Brazil.

Conclusion and Implications

• The high seroprevalence of antibodies against SnSAG4 suggests that S. neurona is likely widespread in the environment in Brazil, leading to significant exposure and infection rate in horses. This prevalence is an issue of concern as S. neurona can potentially cause a serious neurological disease in horses called Equine Protozoal Myeloencephalitis.
• The low seroprevalence of Neospora spp., on the other hand, indicates that this pathogen is less of a concern in horses in Brazil. Nonetheless, it does not entirely rule out the possibility of infection or associated health risks.
• This study could play a crucial role in establishing targeted disease control strategies and improving health management practices in equine populations in Brazil and potentially other areas with similar infection patterns.