A viabilidade de uma formulação do fungo Monacrosporium thaumasium (Drechsler, 1937) foi avaliada no controle biológico de nematóides parasitos gastrintestinais de bovinos. Dois grupos de sete bezerras cada, mestiças Holandês ´ Zebu, de quatro a seis meses de idade, foram colocados em pastagens de Cynodon dactilon. No grupo A, cada animal recebeu 20g de pellets (formulação granulada) de M. thaumasium via oral, duas vezes por semana, durante quatro meses, com início na estação chuvosa (outubro, 2001). No grupo B (controle), as bezerras não receberam nenhum tratamento. As contagens de ovos por grama de fezes (OPG) e das larvas infectantes encontradas na pastagem do grupo B foram significativamente maiores (P<0,05) do que as do grupo A e a diferença entre o OPG dos animais dos grupos A e B, no final do experimento, foi de 88,8%. O gênero Cooperia foi o mais prevalente em ambas as pastagens. Conclui-se que a aplicação de pellets de M. thaumasium na dosagem e periodicidade de aplicação usadas foi eficiente no controle de nematóides parasitos gastrintestinais de bovinos.

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The Fundão Dam breached on 5 November 2015 (the “Event”), resulting in the release of tailings, water, scoured sediment and/or soil, and other debris to downstream watercourses. Statistical analyses using historical and recent water quality measurements were conducted to assess the extent to which water quality in the Rio Doce was recovering to baseline conditions. A review of station‐ and/or parameter‐specific water quality time series in the Rio Doce revealed two challenges: pre‐Event data imbalance and seasonality. Due to the combined effects of these two factors, data gathered from Rio Doce water quality stations before the Event likely underestimated concentration ranges and limited the usefulness of common recovery assessment techniques such as times series and water quality standard exceedance analyses. These challenges were addressed by calculating quarterly and watershed‐specific river‐to‐tributary ratios. R code was used to produce spatiotemporal time series for 44 investigated parameters that were measured both before and after the Event. The water quality recovery durations shown by the parameter‐ and/or region‐specific river‐to‐tributary ratio time series indicated that (a) turbidity provides the most conservative measure for water quality recovery; (b) chemical parameters associated with the tailings, like manganese and iron recovered faster than turbidity; and (c) other investigated parameters unrelated to the tailings showed either no discernable impact or rapid recovery after the Event. The resulting parameter‐ and/or region‐specific river‐to‐tributary ratio time series provided reliable and quantifiable estimates of water quality recovery durations. The water quality in the region furthest from Fundão Dam, in Espírito Santo, recovered one year after the Event, while water quality in the closest region to Fundão Dam, upstream of Risoleta Neves (Candonga) Dam, recovered 4.2 years after the Event. Integr Environ Assess Manag 2023;00:1–13. © 2023 Newfields Companies, LLC. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

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