Interação entre hemoparasitos em anuros da Amazônia central: Coinfecção, suscetibilidade e fatores determinantes

The susceptibility of anuran amphibians to parasitic infections can vary according to behavior, habitat and interspecific interactions. However, these generalizations are mainly based on studies of other taxonomic groups and ecological systems that are not Neotropical. In this sense, we investigated how ecological and environmental factors can influence the interaction between hemoparasites (trypanosomes and hemogregarines) and their anuran hosts in Central Amazonia. To detect the presence of hemoparasites, blood smears were examined using light microscopy to identify and quantify the parasites. Statistical tests were applied to assess the susceptibility of different anuran species to hemoparasite infection and to determine the association between trypanosome and hemogregarine infections. Generalized linear models were used to investigate the influence of environmental and host characteristics, such as proximity to water bodies and perch height, on the abundance of parasites. We found a hemoparasite prevalence of 33.3% (n = 41/123) and some species were more susceptible to infection than others, of which Osteocephalus oophagus was the most parasitized species. Co-infection by hemoparasites was significant, suggesting interactions between trypanosomes and hemogregarines within the host. Proximity to water bodies showed a weak relationship with the abundance of hemoparasites. However, individuals of the same species collected at higher elevations showed a lower quantity of hemogregarines in the blood smears examined, indicating that the vertical stratum may present different levels of exposure to vectors, with higher elevations being less exposed. Our results indicate that the habitat can influence the transmission and prevalence of hemoparasites, but the individual characteristics of the host can play an even more decisive role in the dynamics of infections.