Gastrointestinal Parasites in Himalayan Musk Deer ( Moschus leucogaster Hodgson, 1839) and Sympatric Livestock in Gaurishankar Conservation Area, Nepal

BACKGROUND: Parasite infections threaten both domesticated and wildlife populations. Shared resources between wildlife and domesticated ruminants increase the risk of cross-transmission, underscoring the need for infection research. This study aimed to determine the composition, prevalence, and habitat-dependent patterns of gastrointestinal parasites in endangered Himalayan musk deer (Moschus leucogaster) and sympatric livestock (chauri and horses) in Lapchi Valley of Gaurishankar Conservation Area. METHOD: Using a cross-sectional, comparative, systematic, and grazing regime-based study design along belt transects, a total of 97 fecal samples of Himalayan musk deer (n = 67) and livestock (n = 30) were collected from livestock-influenced habitat and natural habitat. A prior sample size calculation was not performed; instead, all accessible musk deer latrines and available livestock encountered during the survey period were sampled. Parasite taxa were identified based on morphological characteristics. RESULTS: The analysis revealed an overall prevalence of 94.8%. Twelve parasites were identified, including two protozoans (Eimeria sp. and Entamoeba sp.), eight nematodes (ascarid eggs, Bunostomum sp., Capillaria sp., Dictyocaulus sp., Muellerius capillaris, Oxyuris sp., Strongylida larvae, and Trichostrongylus sp.), one cestode (Moniezia sp.), and one trematode (Paramphistomum sp.). Among musk deer samples (n = 67), 92.5% were positive, with nematodes being most prevalent. Six parasite species were common to both livestock and musk deer, indicating potential cross-transmission. Muellerius capillaris was most prevalent in musk deer (85.1%), while Strongylida larvae were most prevalent in livestock (56.7%). Higher prevalence in musk deer was observed in livestock-influenced areas than in natural habitats. CONCLUSIONS: Although parasite compositions showed distinct clustering by host, the presence of six shared species underscores the risk of spillover. These findings accentuate the need for integrated parasite management strategies that minimise livestock-wildlife contact as a critical component of conservation planning in protected areas.