Endoparasite Survey in Amazonian Manatees (Trichechus inunguis) under rehabilitation in the Peruvian Amazon

Manatee populations are declining worldwide, and all currently existing species are considered vulnerable by the IUCN. The Amazonian manatee, (Trichechus inunguis) has barely been studied, and information on their endoparasites is scarce. Most Amazonian manatees that are treated and nurtured in rescue centres are juvenile animals and the most common problems are of gastrointestinal nature leading to inappetence, diarrhoea, cachexia and even death. Endoparasites play an important role in the well- being of wild animals in captivity as well as in wild population. The present study is the first to examine faecal samples from Amazonian manatees in Peru using molecular tools. We investigated faecal samples from 23 T. inunguis that were kept at rescue centres in the Loreto department, Peru and screened them for Enterocytozoon spp., Giardia spp., Cryptosporidium spp., Eimeria spp., intestinal nematodes and trematodes using coproantigen ELISAs, coproscopical analysis and molecular tools. In 11 of the 20 juvenile animals (55%) protozoan parasites from the genus Eimeria were found. No metazoan parasites were documented in any of the manatees in the present study. In total two morphologically different, not yet genetically described Eimeria species were identified. One of them seems to be Eimeria trichechi which has only been described once in Amazonian manatees from Brazil. Eimeria cf. trichechi infections were not found to lead to clinical coccidiosis in this study. The second Eimeria sp. was associated with clinical symptoms of coccidiosis in a young Amazonian manatee, which showed gastrointestinal symptoms including diarrhoea, inappetence and cachexia.