Prevalence of gastrointestinal parasites in the Nicobar long-tailed macaque (Macaca fascicularis umbrosus) on the Nicobar Group of Islands, India

Changes in the habitat can drive the species to adapt to the changing environment that may lead to a risk of infection and the emergence of diseases. The prevalence of gastrointestinal parasites (henceforth endoparasites) in a species is an indicator of changing habitat conditions, and the study of the same is important when the species is restricted to a few islands. Macaca fascicularis umbrosus, endemic to Great Nicobar, Little Nicobar and Katchal islands. The December 2004 tsunami destroyed much of its habitat and pushed them to agriculture fields, leading to a conflict. To study the endoparasites in these macaques, we collected 160 faecal samples from five groups of macaques on Great Nicobar, one group on Little Nicobar, and two groups on Katchal between 2014 and 2016. The endo­parasite eggs and cysts were isolated from the faecal samples using flotation concentration and sedi­mentation techniques in the laboratory. The number and percent prevalence of endoparasites recorded in Great Nicobar, Little Nicobar and Katchal was 13, 5 and 3, and 69.38%, 60.00% and 39.39% respectively. The Campbell Bay group on Great Nicobar had 12, whereas other groups had 2–7 endoparasite taxa. The protozoan load was higher than the helminth load but the overall, helminth, and protozoan load did not differ between the islands. Ascaris sp., Oesophagostomum sp., Strongyloide ssp., Bunostomum sp. and Balantidium coli were the predominant endoparasites. The persistence of macaque with people probably has increased the richness and prevalence of endoparasites on Great Nicobar than in the other two islands.