Prevalence, distribution, and associated risk factors of major equine endoparasitic infections in South Gondar Zone, Northwest Ethiopia.

Endoparasites remain major constraints on equine health and productivity in Ethiopia; however, epidemiological data from northwestern regions are limited. This study investigated the occurrence, parasite diversity, infection intensity, and risk factors associated with endoparasite infections in equines in northwestern Ethiopia. A cross-sectional study was conducted using coprological examinations complemented by postmortem inspections. Standard parasitological techniques were employed, and multivariable logistic regression analysis was used to identify predictors of infection. Data were analyzed using SPSS version 27. Overall, 411 of 720 equines were infected, giving an overall prevalence of 57.1% (95% CI: 53.5-60.7). Endoparasite infections were common, with Strongyle spp. (23.5%; 95% CI: 20.5-26.7) and Parascaris spp. (10.1%; 95% CI: 8.1-12.7) identified as the predominant parasites. Postmortem examination revealed a diverse range of endoparasites, including gastrointestinal and respiratory nematodes, cestodes, trematodes, and botfly larvae. Most infections were of low to moderate intensity. Multivariable analysis showed that species, age, body condition score, and season were significantly associated with infection (p ≤ 0.05). Young equines were at higher risk compared with older animals (AOR = 2.80; 95% CI: 1.63-4.80; p < 0.001). Equines with poor (AOR = 9.13; 95% CI: 5.04-16.52) and medium (AOR = 3.84; 95% CI: 2.28-6.46) body condition scores were significantly more likely to be infected than those in good condition (p < 0.001). Donkeys had a significantly lower likelihood of infection than horses (AOR = 0.18; 95% CI: 0.05-0.62; p = 0.007), while infection risk was higher during the wet season compared with the dry season (AOR = 2.72; 95% CI: 1.93-3.83; p < 0.001). Sex was not significantly associated with infection status. In conclusion, endoparasite infections are widespread among equines in the study area and are strongly influenced by host characteristics and seasonal factors. These findings provide baseline epidemiological evidence to inform targeted parasite control strategies, with priority given to young equines, animals in poor body condition, and wet-season interventions.