BIOMARCADORES HEPÁTICOS E SANGUÍNEOS: FERRAMENTAS MORFOLÓGICAS PARA ESTUDOS DE IMPACTOS AMBIENTAIS DA ATIVIDADE AGRÍCOLA EM ANUROS

Abstract

The growth of agricultural areas around the world not only raises environmental concerns, but also about the health of non-target organisms that inhabit nearby locations those areas. Contaminants of agricultural origin, in especial, pesticides and fertilizers, contaminate the soil and can reach bodies of water through direct application or runoff. Therefore, animals dependent on terrestrial and aquatic habitats can be harmed. In this way, amphibians are bioindicators of environmental quality, due to their life cycle dependent on aquatic and terrestrial environments, in addition to their sensitivity to contamination, since it presents skin permeability. In addition, there is a special interest in the evaluation of these animals due to the population decline observed for the group. Techniques such as the micronucleus (MN) test and other erythrocyte nuclear abnormalities (ENAs) and the analysis of hepatic melanomacrophages are tools for assessing changes caused by xenobiotic agents. In this sense, this study presents two chapters, where the first investigates the effects of soybean management on the frequency of MN and other ENAs, and the area occupied by anuran liver melanomacrophages Leptodactylus fuscus compared to a preserved area (Unit Conservation). Significant differences were finding between the areas for the analyzes, with animals from the agricultural area with a higher frequency of genotoxic damage (MN and ENAs) and a smaller area occupied by melanomacrophages. The second chapter presents an assessment of the possibility of reducing damage caused by the management of agricultural areas of soy and sugar cane in anurans of the species Physalaemus nattereri after these animals are free from exposure to these areas. The MN test and other ENAs and the analysis of melanomacrophages also demonstrated significant differences between animals exposed to agricultural areas and animals that have undergone a exposure free period. There was a reduction in the frequency of MN and ENAs and an increase in the area occupied by melanomacrophages in animals after the period without exposure. Thus, this work brings more evidence that the management of agricultural areas can cause damage to amphibians and shows that, if the exposure ceases, these damages can be reduced.