Composição e estrutura das comunidades de helmintos de Didelphis marsupialis Linnaeus. 1758, (DIDELPHIMORPHIA, DIDELPHIDAE), em ambiente de transição dos biomas Cerrado e Amazônia no estado do Mato Grosso

Abstract

Among the marsupial species in Brazil, the genus Didelphis is the most parasitized by helminths. Despite the wide occurrence of endoparasites in wild animals of the genus Didelphis, there is a lack of information about the helminth fauna of these animals in the Amazon Forest biome. Furthermore, community structure studies of helminths are rare in Brazil and none have been carried out so far for didelphids in the Amazon biome. The objectives of this thesis were to describe the species composition and analyze the structure of helminth communities of the opossum Didelphis marsupialis from the transitional phytogeographic domain Amazon Forest and Cerrado. This study seeks to expand knowledge of the helminthological fauna of these wild hosts with great importance in carrying out an inventory of species diversity and in determining the risk to public and animal health. In this manuscript we report the occurrence of some helminth species found in Didelphis marsupialis, popularly known as blackeared opossum. In the study area, they were collected in 17 transects, in the municipality of Sinop and Cláudia, Mato Grosso, Brazil. The contents of the alimentary canal were individually processed and examined under a stereoscopic microscope at 10X. One of the most important results obtained was the presence of the helminth Didelphonema longispiculata found for the first time in Brazil, it was observed with a prevalence of 43.75% (14/32) of positive animals, mean intensity of 7.71 and abundance of 3 .38. Didelphonema longispiculata, which had only been reported in the United States in Didelphis virginia-na and Tirinidad and Tobago in the insular opossum Didelphis marsupialis insularis. All morphometry of the parasite is in accordance with the descriptions in the literature for this species Didelphonema longispiculata, which confirms the identification of the species, this study also presents molecular and phylogenetic analysis, images by optical microscopy and electron scanning microscopy, which are not had been shown previously. The results indicated that the helminthic fauna of D. marsupialis in the south of the transitional Amazon with Cerrado was similar to the helminthic fauna observed in other regions and to the more congenerous species D. aurita and D. albiventris. Host sex was not related to abundance or prevalence. However, the age of the host influenced the abundance and prevalence of acanthocephalans and the nematode D. longispiculata.