Is it possible to estimate the intensity of intestinal nematodes through fecal material studies on wild mammals?

EZQUIAGA M.C.; ABBA A; NAVONE G T

Mendoza

Congreso; X Internacional Mammalogical Congress; 2009

The concentration of parasites, most notably the number of parasite eggs, is an important parameter in epidemiology and the diagnosis of infections. The objective of this work was finding a simple tool that allows estimating the parasite intensity to contribute to the health state knowledge of wild mammal’s populations. Two armadillo species Zaedyus pichiy and Chaetophractus vellerosus (Xenarthra), from a net South American ancestry and a wide distribution in Argentina, were taken as study model. The gastrointestinal tract was examined (n = 4) and fecal samples were collected of the same individuals. These samples were analyzed with a flotation method of saturated sugar solution and the parasite load was estimated through a MacMaster chamber expressed as eggs per gram of feces (epg) for each morphological egg type. Nematodes found in the intestinal tract were identified as Aspidodera scoleciformes and A. fasciata (Aspidoderidae), and Moennigia sp. (Molineidae). The proportion of sexes was calculated and in all parasites species it was 1:1 average. The epg was multiplied by the fecal material amount that these animals eliminate per day (5 to 7 gr). The obtained value was divided by the number of mature females found in the alimentary canal of each host and thus the number of eggs/female/ day number was estimated (biotic potential). An Aspidodera female oviposits among 14-22 eggs per day and a Moennigia sp. female does it around 20 eggs per day. The number of female nematodes can be inferred with this information starting from the epg and the number of males arises from the proportion that characterizes each species. These techniques are erected as quantitative tools not only for revealing the presence of parasite species but also for estimating their intensity. Advances in parasitological research on wild animals will allow referring areas, parasite and host associated species, and an evaluation of the antropic impact.