Gastrointestinal helminth and protozoan infections of wild mammals in four major national parks in Sri Lanka

摘要

A cross-sectonal, coprological survey of gastrointestnal (GI) parasites of wild mammals in four major Natonal Parks in SriLanka: Wilpatu, Udawalawe, Wasgamuwa, and Horton Plains was carried out during November 2016 to August 2017. Fresh fecal sampleswere collected and analyzed using sedimentaton technique, iodine & saline smears, and Sheather’s sucrose fotaton for morphologicalidentfcaton parasite eggs, cysts, and larvae. A modifed salt fotaton was carried out for egg counts. Seventy samples from 10 mammalspecies: Asian Elephant, Spoted Deer, Water Bufalo, Sambar, Indian Hare, Asian Palm Civet, Sloth Bear, Wild Boar, Grey Langur, Leopard,and four unknown mammals (two carnivores, one herbivore and one omnivore) were analyzed. Most were infected (94.3%) with more thanone GI parasites. The highest prevalence of infecton was recorded in Horton Plains (100%), followed by Wasgamuwa (92.8%), Wilpatu(90.4%) and Udawalawe (75.0%) with a signifcant diference among four parks (Chi square test; χ2=35.435; df=3; p0.001). Nineteen speciesof GI parasites were recorded, of which Entamoeba, Isospora, Balantdium, Fasciola, Moniezia, Dipylidium, strongyles, Toxocara, Trichiurusand hookworms were the most common. Strongyles (62.1%) and Entamoeba (80.3%) were the most prevalent helminth and protozoaninfectons, respectvely. Overall, there was no diference in the prevalence of protozoans (84.3%) and helminths (87.1%; χ2=1.0; df=1;p=0.317). In carnivores, Entamoeba, Balantdium, Moniezia, strongyles and Strongyloides were common and in herbivores, Entamoeba,strongyles, Strongyloides and Toxocara were common. The quanttatve analysis showed strongyles (17.639 EPG) and Isospora (18,743OPG) having the highest infecton intensity among helminthes and protozoans, respectvely. This study provides baseline informaton of GIparasites and their distributon in wild mammals in the four natonal parks. Although the prevalence of GI infectons was high, their intensityshows that they could be incidental infectons. When the prevalence of an infecton is high but the intensity is low, it is unlikely to be amajor health problem leading to the endangerment of a species. Parasitc diseases can not only afect conservaton eforts, but they are alsonatural selecton agents and drive biological diversifcaton, through infuencing host reproductve isolaton and speciaton.