Exposição ao glifosato em Podocnemis unifilis (testudines:podocnemididae): implicações para o crescimento, histologia hepática, e a capacidade de interação com Mauritia flexuosa

Abstract

In recent decades, biomes such as the Cerrado and the Amazon have been exploited for agricultural purposes. These anthropogenic alterations related to the advance of the agricultural frontier lead to an increase in the use of pesticides. This disordered use causes contamination of aquatic ecosystems through "derive" increasing the continuous exposure of non-target organisms to contaminants. The effects of glyphosate exposure have already been described in different organisms, but studies addressing alterations in growth and hepatological responses in freshwater Testudines, and consequently means to mitigate these alterations, are still scarce. Thus, this work aimed to evaluate the alterations in growth rate and histological changes in the liver of juvenile Podocnemis unifilis, and to see the capacity for interaction with Mauritia flexuosa as a mitigating agent. Specimens were exposed to glyphosate at the maximum dose permitted by CONAMA (Brazilian National Council for the Environment), with and without supplementation based on M. flexuosa, and were evaluated for growth rate over a 30-day period, with liver alterations observed at the end of the experiment. The results indicated no significant difference in growth, but revealed liver alterations such as accumulation of melanomacrophages and vascular congestion in specimens exposed to herbicide. Therefore, studies like this highlight the relevance of integrating physiological and histopathological data to understand the impacts of contamination on turtles, also evidencing potential risks to traditional communities that use them for food.