Changes in the natural landscape and the indiscriminate use of pesticides can have a major impact on aquatic environments and have contributed to the worldwide decline of amphibian populations. In the present study, we sampled tadpoles of three anuran amphibians (Boana albopunctata, Physalaemus cuvieri, and Dendropsophus minutus) from ponds in six different agricultural landscapes of the Brazilian Cerrado savanna and evaluated whether and to what extent genotoxic and mutagenic damage was related to land use (the amount of forest and agricultural remnants, and related physicochemical factors) and the presence of pesticides in the water of the study ponds. We also evaluated the hepatotoxicity in P. cuvieri, which was the most abundant species at five of the six sampling points. Clomazone and Atrazine were the most common pesticides found in the ponds. The B. albopunctata and P. cuvieri tadpoles presented similar patterns of DNA damage among the sampling points. The least DNA damage was found in the D. minutus tadpoles, although this species was present in only one of the study ponds. More binucleated and anucleated cells were observed in B. albopunctata, but there was no significant variation among species in terms of the number of micronuclei or other erythrocytic nuclear abnormalities. Land use and physicochemical factors did not explain the variation in the DNA damage observed in the three anurans. The hepatotoxicity analyses of P. cuvieri revealed the presence of a series of alterations, including the enlargement of the sinusoids, vacuolization of the hepatocytes, the infiltration of inflammatory cells, hepatic steatosis, and dilation of the blood vessels. The interaction between physicochemical factors and the biomarkers analyzed in this study is complex. In particular, it will be important to better elucidate which factors are contributing, either directly or indirectly, to the decline of anuran amphibian populations, especially in threatened biomes, such the the Brazilian Cerrado. In this case, we would encourage further in situ studies that assess the ecotoxicology of the landscape, together with the systematic monitoring of aquatic environments, in order to guarantee the long‐term integrity of amphibian populations, and those of other organisms that play an essential functional role in the ecosystem.

The objectives of this review article were to examine the dynamics of Varroa destructor infestation levels in Africanized honey bees (AHB) in Brazil, since this parasitic mite was first detected in 1977. Data from published research articles, conference proceedings, congress abstracts, and unpublished data obtained from academic researchers was included. Although mite infestations varied significantly along the years, there were no indications that varroa negatively impacted Brazilian apiculture. The mean infestation levels have remained around 4.5 mites per 100 adult bees, with a median of 3.8, during the last 45 years. Adult bee and worker brood infestation rates were found to be similar, though with some geographical variation, including a tendency for higher infestations in the southern regions of the country. Various researchers have suggested that the low infestation levels could be a consequence of the tropical and subtropical climate, honey bee hybridization, grooming and hygienic behaviors, honey bee and mite genetic factors, low nutritional stress, management practices, low migratory stress, and environmental conditions. The lack of a need for chemical treatment of varroa infestations facilitates apiary management and favors organic beekeeping throughout the country. However, though AHB colonies and beekeeping in Brazil thrive without the need for treatment measures, more research should be conducted to better assess the impact that the low varroa mite infestations have on AHB colony health and productivity.

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Nos últimos anos, o Brasil está entre os maiores consumidores de agrotóxicos do mundo. Sabe-se que estes produtos são usados em lavouras e se fazem necessários para a produção agrícola em larga escala. No entanto, quando utilizados de modo indiscriminado e sem o devido treinamento, podem impactar a saúde ambiental e humana. Para o meio ambiente, os descartes errôneos de tais produtos, assim como a liberação para cursos de água, acabam atingindo espécies não alvo, levando a ameaças para a sobrevivência de muitas delas. Para os humanos, a exposição prolongada, especialmente em agricultores que lidam ocupacionalmente com os agrotóxicos, pode acarretar, a médio e longo prazos, doenças genéticas, como diversos tipos de cânceres. Dessa forma, o uso de agrotóxicos é um fator constituinte na ocorrência de agravos à saúde.