ECOLOGICAL ASPECTS OF NEMATODE PARASITES OF Didelphis aurita (DIDELPHIMORPHIA, DIDELPHIDAE) IN URBAN-SYLVATIC HABITATS IN RIO DE JANEIRO, BRAZIL

Abstract

Despite the widespread occurrence and the great number of studies of the common opossum Didelphis aurita (Didelphimorphia, Didelphidae), there is a serious lack of information about helminth parasitism in these species. The synanthropic characteristic of these animals may influence their parasite fauna and the ecological parameters. We evaluated the abundance, intensity, prevalence and spatial aggregation of the most abundant nematodes of the large intestine and stomach, recovered from the common opossum D. aurita, in Pedra Branca State Park and its surroundings, which includes the FIOCRUZ Atlantic Forest Campus, Rio de Janeiro, Brazil. We investigated the effects of anthropic disturbances on the helminth populations comparing the parameters in relation to host habitat types, season and host gender in order to understand the ecological host-parasite interaction. The animals were sampled in three different habitats. We conducted eight small mammal samplings in different seasons and collected 48 individuals of the common opossum. The nematode species found in the large intestine were Aspidodera raillieti and Cruzia tentaculata while Turgida turgida was found in the stomach. Cruzia tentaculata was the species with the highest abundance, intensity and prevalence indices. The three species had a highly aggregated distribution. No species had significant difference in prevalence when compared with host habitat types, host gender or season. Cruzia tentaculata had higher intensity in the rainy season, which suggests that rainfall contributes to the development of the life cycle of this helminth. Turgida turgida had higher abundance in the disturbed forest habitat, suggesting that the presence of intermediate hosts may be favoured by the characteristics of this environment.

First study on the helminth community structure of the neotropical marsupial Metachirus myosuros (Didelphimorphia, Didelphidae)

“…This pattern is most common in species with a polygamous mating system (Poulin, 2007), but there is no information in the literature about the mating system of these species. Nonetheless, similar results were found by Antunes (2005), Castro et al (2017) and Costa-Neto et al (2019) for C. tentaculata.…”

Helminth metacommunity structure of wild rodents in a preserved area of the Atlantic Forest, Southeast Brazil

“…Parasites have important ecological roles in ecosystems because they affect the fitness of their hosts, promote changes in their physiology and population dynamics, regulate host populations, mediate competition and predation, and influence diversity through a cascade effect (POULIN, 2007). The occurrence and distribution of parasites in host populations depend on several factors that include host and parasite attributes, such as phylogenetic relationships, host behavior, susceptibility to parasites (BROUAT et al, 2007;WOLINSKA & KING, 2009), as well as characteristics of the environment such as seasonality and habitat (WOLINSKA & KING, 2009;SIMÕES et al, 2010;CASTRO et al, 2017).…”

Gleasonian structure in the helminth metacommunity of the opossumDidelphis albiventrisin two extremes of the Atlantic Forest

“…Other studies have found similar results for C . tentaculata (Müller, 2005; Castro et al ., 2017; Costa-Neto et al ., 2019; Cirino et al ., 2020).…”