Prevalence of gastrointestinal parasites in Tibetan sheep in alpine zone of North Sikkim, India

Prevalence of gastrointestinal (GI) parasites in native Tibetan sheep (Ovis aries), a critically endangered small ruminant of North district of Sikkim, India was studied during July 2014 to June 2015. Of the 213 animals examined, 71 (33.33%) were found positive for different GI parasites. The overall prevalence of different parasites recorded was strongyles (67, 31.46%), coccidia (52, 24.41%), Strongyloides spp. (41, 19.24%), Moniezia spp. (37, 17.37%), Nematodirus spp. (25, 11.73%), amphistomes (12, 5.63%), Dicrocoelium spp. (9, 4.22%) and Trichuris spp. (8, 3.76%). The faecal egg counts (eggs per gram of faeces, epg) of nematodes ranged from 100 to 2700 with higher load during rainy and post rainy seasons. A higher infection rate was recorded in animals above 2 years of age (39.29%) followed by 1 to 2 year (24.14%) while those below 1 year of age showed only 13.33% prevalence and the parasites mostly recorded were Haemonchus spp., Eimeria spp. and Moniezia spp. The seasonal distribution of parasitism indicated a higher percentage of infestation in autumn (44.26%) and summer (37.74%) as compared to spring (31.92%) and winter (17.31%).