Evaluation of the intrinsic and extrinsic ecological effects on the helminth communities of Didelphis albiventris (Didelphimorphia, Didelphidae) in Atlantic Forest areas.

The white-eared opossum Didelphis albiventris is widely distributed throughout Brazil and hosts several parasite species. This study aimed to analyze the influence of intrinsic (sex and age of hosts) and extrinsic (locality and type of land use) factors on the helminth communities of the white-eared opossum in areas of the Atlantic Forest. Helminth samples from 93 D. albiventris specimens from six different localities were used: Belo Horizonte, MG; Curitiba and Guaíra, PR; Porto Alegre, RS; and Mamanguape and Santa Rita, PB. Fourteen species of helminths were identified: Aspidodera raillieti, Cruzia tentaculata, Turgida turgida, Viannaia hamata, Rhopalias coronatus, Rhopalias horridus, Duboisiella proloba, Travassostrongylus orloffi, Travassostrongylus sextus, Brachylaima advena, Plagiorchis didelphidis, Trichuris minuta, Trichuris didelphis, and Oligacanthorhynchus microcephalus. Female hosts and adult hosts had greater helminth species richness and abundance. The helminth species richness and abundance in D. albiventris were influenced by intrinsic (sex and age of the host) and extrinsic (locality and land use) factors with the locality being the main determinant. The structure of the helminth infracommunities varied spatially, with greater differences with increasing geographic distance, highlighting the complexity of host‒parasite interactions in wildlife.