Seroprevalence, Risk Factors, and Environmental Correlates of Babesia caballi, Toxoplasma gondii, and Coxiella burnetii in Equids from Southwestern Greece.

Equids, primarily horses, are mostly used for recreational purposes, although in some rural areas they also serve as working animals, maintaining close and frequent contact with humans. Their risk of exposure to vector-borne and zoonotic pathogens can be affected by host-related factors, management practices and environmental conditions. This study aimed to investigate the seroprevalence and associated risk factors for infections by Babesia caballi, Toxoplasma gondii, Coxiella burnetii, and Borrelia burgdorferi sensu lato in equids from Southwestern Greece. A total of 159 equids were tested using commercial serological assays. Weighted prevalence estimates were applied to account for unequal sampling. Associations were assessed using chi-square tests and logistic regression. Ecological niche modelling was employed to evaluate geographic patterns and environmental correlates. Seroprevalence was highest for B. caballi (8.81%), followed by T. gondii (7.55%) and C. burnetii (1.26%). No seropositive animals were detected for B. burgdorferi sensu lato. Ecological niche modelling showed acceptable predictive performance for B. caballi, with BIO14 and BIO6 emerging as the main environmental predictors. In contrast, the T. gondii model exhibited unacceptable predictive performance, and its environmental associations should therefore be interpreted cautiously. Complementary Random Forest analyses yielded comparable environmental rankings but showed higher classification performance for T. gondii than for B. caballi. Overall, the findings contribute to understanding pathogen exposure patterns in equids and underscore the importance of integrating epidemiological and environmental data in surveillance efforts.