Helmintos de veados-mateiros (Mazama americana) dos municípios de Axixá do Tocantins e Araguaína, Tocantins, Brasil

Abstract

Mazama americana is better known as Red Brocket Deer. There are many other names designating the same species of deer which live in forests and nearby rivers. It can be found in almost everywhere inside the national territory. The species is distinguished by its reddish brown color and other characteristics such as posterior arcuate region and robust body, short tail, middle ear, face and elongated slender members which give them flexibility. They are considered frugivorous and selective grazers that prefer parts of plants of higher energy content and easy digestibility. The Red Brocket Deer is not included in the list of endangered animals, but the anthropogenic changes in the natural environment of wild animals may contribute to the population decline of these animals as well as the parasite diversity, mainly from agriculture, where cattle and small ruminants have been created extensively on native pastures and natural forests. Several species of helminths, such as flatworms, trematodes, protozoa and especially nematodes can be found parasitizing domestic and wild ruminants. The following helminth species were observed parasitizing deer: Haemonchus contortus, Haemonchus similis, Trichostrongylus axei, Trichostrongylus colubriformis, Cooperia punctata, Cooperia pectinata, Physocephalus lassancei, Physocephalus sexalatus, Pygarginema verrucosa, Mammonogamus sp, Strongyloides sp, Capillaria sp, Trichuris sp., Thelazia californiensis e Monodontus sp. However the studies of parasites deer are only concerned in describing and redescribing species, although the determination of infection indicators improves the knowledge of the host-parasite relationship. Knowledge of helminth fauna of deer is very important to determine the possibility of transmitting these agents to domestic animals and humans as well as is the need to conduct periodic monitoring through diagnostic tests to aknowledge the magnitude of the infections caused by these agents and guide possible programs to prevent and control parasites of wild hosts. The study aimed to understand the helminth fauna and indicators of brocket deer infections (M. americana) captured in Axixá municipalities of Tocantins and Araguaína. Therefore, six adult deer were used, five males and one female, euthanized and necropsied in situ, where the incision and washing of each anatomical segment of the digestive tract was made separately. The contents obtained from washings were preserved in formalin-acetic acid solution and properly packaged and sent to the Laboratory of Hygiene and Public Health of the Federal University of Tocantins for species identification and determination of infection indicators. Parasites were separated by gender and sex and later studied for species identification. Of the six autopsied deer, three had infection, of which 477 were collected nematodes and flatworms. The species of nematodes observed were H. similis, H. contortus, T. axei e C. punctata, with the highest values of the infection indicators for C. punctata e H. similis. The kind of flatworm observed was Moniezia expansa. The same species are reported parasitizing domestic ruminants, in addition deer can host human infecting parasites, and therefore, are of great importance to public health.