Gastro-Intestinal Parasites of Asian Elephant (Elephas Maximus Linnaeus, 1758) in and Around Chitwan National Park, Nepal

Abstract

Asian elephant is an endangered species in Nepal and its numbers are declining day by day. Present study was conducted to assess the prevalence of gastrointestinal parasites in Asian elephant in and around the Chitwan National Park. A total of 20 dung samples from wild elephants were collected by opportunistically from Chitwan National Park whereas as a total of 80 dung samples were collected from 40 captive/domestic elephants by the duplicate sampling technique with interval of 15 days in the month of May 2017. The collected dung samples were preserved in 2.5% potassium dichromate and microscopically examined using the direct smear method and concentration methods. Prevalence of protozoan and helminthes parasites was found to be 90% and 57% in wild and captive/domestic elephants respectively. In both wild and captive/domestic elephants, one protozoan parasite was reported: Eimeria sp. with 15% and 7.5% respectively. Among the helminthes parasites, one genus of cestode was reported from wild elephants: Anoplocephala sp. (10%) but was not found in captive/domestic elephant. Eight different genera of nematodes were identified in wild elephants (Ascaris sp. (45%), Strongyloide sp. (85%), Haemonchus sp. (25%), Trichostrongylus sp. (10%), Dromeostrongylus sp. (30%), Chabertia sp. (15%), Bunostomum sp. (10%), and Nematodirus sp. (10%) whereas four different genera of nematodes were identified in captive/domestic elephants (Ascaris sp. (27.5%), Strongyloide sp. (52.5%), Haemonchus sp. (7.5%), Bunostomum sp. (2.5%). No trematode was reported from the both wild and captive/domestic elephants. Location wise analysis suggested the higher prevalence of gastrointestinal parasite in dung samples collected from Chure area (30%) where as it was found higher from the Khorsar breeding center (15%) and Tiger Tops Tharu Lodge (15%) in captive/ domestic elephant. Mixed infection was reported in wild elephant with double (35%), triple (40%) and multiple infections (15%) but no single infection. However, in case of captive/domestic elephant’s single infection (32.50%) was reported with some mixed infection such double (17.50%) and multiple infections (7.50%). Intensity of parasites suggested that the light infection is prevalent than that of heavy infection in both cases. Comparing the morphologically similar parasites, the statistical analysis showed that there was significant difference in the prevalence of parasites among the wild and captive/domestic elephants (χ xii

2 = 5.0931, P-value= 0.02). However, the parasites such as Dromeostrongylus sp., Nematodirus sp., Chabertia sp., Trichostrongylus sp. and Anoplocephala sp. were only observed in wild elephants.