Altimetry and environmental impact assessment in Mãe-Bá lagoon, Espírito Santo Brazil

The assessment of environmental impacts on water resources is a multidisciplinary topic, as it demands diverse knowledge. Among these, we can mention geoprocessing, water chemistry, nutrient cycling, legislation, ecology, toxicology, among others. The morA avaliação de impactos ambientais em recursos hídricos é um tema multidisciplinar, pois demanda de conhecimentos diversos. Entre esses, pode-se citar, geoprocessamento, química da água, ciclagem de nutrientes, legislação, ecologia, toxicologia entre out

Tecido hepático e corpo adiposo de rã-touro (Lithobates catesbeianus) submetido a diferentes fotoperíodos

The study was conducted to evaluate the liver tissue weight, body fat weight, the fatty somatic index and the liver somatic index of bullfrogs subjected to three photoperiod during the growing phase (initial 30 days) and finishing (60 days). The treatments were 16 h light and 8 h dark, 12 h of light and dark and 8 h light and 16 h dark. The experimental design was completely randomized design with three replications. We used 36 bullfrogs/m2 weighing from 22 to 28 g. The results were submitted to ANOVA and Tukey Test at 5% probability. Differences were found for the weight of body fat, liver tissue weight, liver somatic index and fatty somatic index the bullfrog to the treatments and the study periods and there is greater accumulation of energy to ninety days. The photoperiod did not influence body weight and fat weight of the liver tissue of bullfrog at the end of the fattening period and the difference fatty somatic index and liver somatic index were influenced by body weight of animals

Histopathological aspects of the liver of free-living and farmed bullfrogs (Lithobates catesbeianus)

The objective of this study was to compare the histopathological aspects of the liver of free-living and farmed bullfrogs (Lithobates catesbeianus). Thirty liver samples were collected from young and adult bullfrogs in the states of Minas Gerais and Rio de Janeiro, Brazil. Marked blood congestion and even hemorrhage and a large number of melanomacrophages were observed in most of the livers from free-living bullfrogs. Additionally, hepatocytes showed cytoplasmic eosinophilia and some showed nuclear hypertrophy and presence of microvesicular steatosis; small foci of infiltrates of mononuclear cells were observed in some samples, as well as a thicker capsule. In the farmed bullfrogs, cytoplasmic rarefaction was normal. Morphologically, unlike the livers of animals reared on farms, the livers of free-living animals did not show any evidence of protein-mineral deficiency, characterized by cytoplasmic vacuolation and a larger number of melanomacrophages, suggesting greater aggression to the liver parenchyma, probably due to environmental toxicity. Free-living bullfrogs feed on proteins of better biological value, derived from animals preyed in the natural environment

Histopathological aspects of the liver of free-living and farmed bullfrogs (Lithobates catesbeianus)

ABSTRACT The objective of this study was to compare the histopathological aspects of the liver of free-living and farmed bullfrogs (Lithobates catesbeianus). Thirty liver samples were collected from young and adult bullfrogs in the states of Minas Gerais and Rio de Janeiro, Brazil. Marked blood congestion and even hemorrhage and a large number of melanomacrophages were observed in most of the livers from free-living bullfrogs. Additionally, hepatocytes showed cytoplasmic eosinophilia and some showed nuclear hypertrophy and presence of microvesicular steatosis; small foci of infiltrates of mononuclear cells were observed in some samples, as well as a thicker capsule. In the farmed bullfrogs, cytoplasmic rarefaction was normal. Morphologically, unlike the livers of animals reared on farms, the livers of free-living animals did not show any evidence of protein-mineral deficiency, characterized by cytoplasmic vacuolation and a larger number of melanomacrophages, suggesting greater aggression to the liver parenchyma, probably due to environmental toxicity. Free-living bullfrogs feed on proteins of better biological value, derived from animals preyed in the natural environment

Evaluating the Trace Element Concentration in Sediments and Assessing Their Genotoxicity in Ichthyofauna of a Coastal Lagoon in Southeastern Brazil

Lacustrine ecosystems are constantly affected by industrial and domestic effluents, which are considered to be the main sources of trace elements in the environment. The physicochemical characteristics of trace elements undergo modifications that can cause reversible genotoxic damage to ichthyofauna. This study aimed to assess the environmental quality of a lagoon (Mãe-Bá) that receives industrial effluents from one of the largest iron ore companies in the world, located in southeastern Brazil. The physicochemical parameters of the lagoon water were analyzed monthly, the trace element levels in the sediment were quantified, and the risk of genotoxic damage to fish was quantified using a micronucleus test and comet assay. We verified the poor environmental quality of the lagoon, and strong anthropic action was evident, with particularly high levels of Cr and Ni and genotoxic damage being observed in fish. It is not possible to state a relationship between the increase in Cr and Ni with the mining company since we found high concentrations of these elements in a reference lagoon (Nova Guarapari) with no connection to the mining company. Even if the bioavailability of the trace elements in the water resource is low or if their concentration is below the permitted limit, their presence can cause genotoxic damage. These findings can enable us to assist in planning suitable remediation strategies to decrease the genotoxic effects observed in these sensitive eco-systems. A multidisciplinary approach is needed in studies involving ecotoxicology to develop conservation strategies for both the biotic and abiotic environments