Haemosporida em Turdus albicollis (AVES: Turdidae) e Pyriglena leucoptera (AVES: Thamnophilidae) na Mata Atlântica da Costa Verde do Estado do Rio de Janeiro

Abstract

Hemoparasites like Haemosporida order are causative agents of malaria in birds and humans and can generate significant effects in avian hosts. They are considered good models for studies of parasite-vector-host interactions and coevolution. The present study aimed to: evaluate the prevalence of Haemoproteus sp., Plasmodium sp. and Leucocytozoon sp. in Turdus albicollis and Pyriglena leucoptera; test whether the prevalence of infection by hemoparasites can be influenced by climatic factors or ecological aspects of the hosts; to test differences in the prevalence and composition of hemoparasitic strains between island and continent in P. leucoptera in the Atlantic Forest in the Costa Verde Region of Rio de Janeiro. The study was carried out in Ilha Grande State Park, RJ (PEIG) and Cantagalo District (Angra dos Reis, RJ). Individuals of P. leucoptera were captured, banded and blood samples were collected for molecular analysis of presence of blood parasites. Blood samples of T. albicollis were analyzed molecularly and by blood smears stained with Giemsa for detection and identification of hemoparasites. The presence of hemoparasites in the DNA of both bird species was detected by means of nested-PCR (Polymerase Chain Reaction) amplifying the hemoparasites cytochrome b gene. PCR positive samples were sequenced to identify the hemoparasite strains. The prevalence of infection in birds and the prevalence for the variables: sex, seasonality and location were calculated. The relationships between these variables and the prevalence of hemoparasites were tested using the Chi- square test. To confirm the identification of the hemoparasite strains, a genetic distance matrix was generated and a Maximum Likelihood analysis was performed using the bootstrap method. Parasites of the gender Plasmodium was the most prevalent parasite in both species, 28% for P. leucoptera and 26% for T. albicollis, and possible new Haemoproteus strains were found in P. leucoptera. Fourteen individuals (20%) of Turdus albicollis were infected by more than one genus of hemoparasites. Individuals of P. leucoptera from Ilha Grande had a greater diversity of hemoparasites, but less prevalence (24%) in comparison to the continent (44%). There was no significant difference in the prevalence of blood parasites between rainy and less rainy periods and between sexes. However, males and females differed in prevalence during the phases of the reproductive period, which may be associated with exposure to vectors and differentiated energy demand between the sexes in this period. Through the results obtained, it is suggested that the ecology of hemosporid infection for the two species studied depends on a set of climatic factors, such as precipitation and the reproductive ecology of hosts and vectors.