Perfil leucocitário e hemoparasitos de Antilophia galeata (Passeriformes: Pipridae) em um fragmento florestal de Cerrado

Abstract

Birds are efficient animals in responding to changes in the balance of the environment, as they are stress-sensitive organisms. The leukocyte profile is considered a reliable tool in the measurement of stress, since it is related to several stressors such as reproduction, low food availability, pollution and parasitism. Birds are affected by diverse parasitic fauna, such as hemoparasites, which may compromise survival and host fitness. The objectives of this work were to examine the leukocyte profile and hemoparasites of a population of Antilophia galeata, and to verify if there is association of both with biological and ecological characteristics of the species. In a Cerrado forest fragment, 151 individuals were captured in 13 field campaigns (06/2013 to 12/2016). The following data were collected: sex, age, biomass, tarsal length, presence/absence of ticks, molt feathers, and brood patch, and blood samples for confection of blood smears, which were analyzed under optical microscope for identification and quantification of leukocytes, micronuclei and parasites. The data collected were divided into two chapters, the first focused on the leukocyte profile, using 89 individuals (captured in 2013-2015) and the second, with a focus on hemoparasites, with 62 individuals (2016). In relation to the leukocyte profile, the number of lymphocytes was higher in males, in non-reproductive phase and in individuals with ticks. There was no difference in any of the leukocyte components in relation to age groups, molt feathers and body condition. The amount of micronuclei was positively related to total leukocyte, H/L ratio, heterophils, basophils and monocytes values. Regarding hemoparasites, 33 (53.2%) individuals were infected, 32 (51.6%) by Plasmodium spp. and one (1.61%) by Haemoproteus spp. There was no difference in parasitemia between the seasons, sexes, presence and absence of reproduction, molt feathers and ectoparasites. There was no correlation between body condition and parasitemia. There was a positive correlation between parasitemia and the total amount of leukocytes, suggesting the increase according to parasitemia, indicating that individuals may be efficient in controlling infections. The present study showed that the leukocyte profile is useful in answering ecological questions, which can be applied in the conservation of the species, because the leukocyte variations are related to stressors such as reproduction and the amount of micronuclei. As for hemoparasites, the results suggest that the population is tolerant to the parasitemia found, since no negative effect was detected.