Fauna parasitária de animais silvestres no Sul do Brasil: epidemiologia e identificação molecular

Abstract

Wild animals can be hosts and/or reservoirs of several parasitic diseases, including zoonotic ones, with potentially significant impact on public health and species conservation. In this sense, the objective was to research and identify the parasitic fauna of wild animals in the microregion of Pelotas, in the south of Rio Grande do Sul, Brazil. For this purpose, carcasses of wild animals run over were collected on highways in the region and submitted to necropsies. Tissue fragments were sampled, and their DNA was extracted. Endo- and ectoparasites were collected and identified morphologically and molecularly. Fecal samples were also analyzedusing the techniques of Centrifugal Flotation with Zinc Sulfate, Spontaneous Sedimentation and Oocyst Sporulation. It was observed that 87.80% of the animals collected were infected by helminths, 51.21% were infested by ectoparasites and 48.78% were affected by both types of parasites. Furthermore, in 69.5% of the fecal samples, we found helminth eggs and/or protozoan cysts/oocysts and 64.9% of the positive samples were parasitized by at least one morphogroup with zoonotic agents. Also, no evidence of the presence of Leishmania spp. DNA was detected in the target animals in the studied region. On the other hand, new records of parasitic fauna were identified such as the first records of Hydatigera taeniaeformis and Ancylostoma caninum infecting Leopardus geoffroyi worldwide; These are the first records of the occurrence of Contracaecum australe infecting Phalacrocorax brasilianus and Rhipicephalus microplus infesting Ozotoceros bezoarticus, both in southern Brazil. The new information contributes to the knowledge about the parasitic fauna of wild animals in southern Brazil and around the world and indicates the need for continued epidemiological studies on the subject in this group of hosts. Such research is crucial for the well-being and conservation of wild animals, domestic populations, and humans.