Anomalias nucleares eritrocitárias como ferramentas de biomonitoramento por aves no cerrado

Abstract

Environmental disturbances, such as air pollution, may affect biological communities in several ways, from species extinction to causing mutagenic effects. One of these latter is Erythrocyte Nuclear Abnormalities (ENAs), which are defined as genetic damage to the cell nucleus. ENAs have been used as biomarkers to assess the potential effects of mutagens in birds. Thus, here we described the ENAs found in free-living bird species in the Brazilian Cerrado and we investigated the influence of air quality in the number of anomalies in both wild species and captive individuals of the Atlantic canary. Bird captures took place in six semideciduous forests from the Cerrado of the State of Minas Gerais in Brazil. Each of these forests were classified according to their air quality. Atlantic canaries were used in experimental trials. Wild birds were identified and both wild species and Atlantic canaries were tagged with metal bands and then, we collected blood to prepare blood smears, which were assessed in optical microscope. We observed 7 related types of ENAs in 11 species of Passeriformes: binucleate cell, erythroplastid, displaced nucleus, slotted nucleus, asymmetric constriction, symmetric constriction, and lobed nucleus The number of ENAs in blood samples from five wild species was related to air quality, i.e. it was higher in areas where air quality was poorer, without distinction among species. The experimental trial showed the same patterns because canaries in the urban areas had higher quantities of ENAs. Therefore, we suggest that bad air quality is the main driver of ENAs in birds, and that this biomarker may be used in biomonitoring studies.