ABSTRACT This study aimed to evaluate the use of microalgae meal (Aurantiochytrium sp. and Nannochloropsis spp.) as a substitute for fish oil in the diet of shrimp Penaeus vannamei reared in a clear water system. In the diet of these animals, the concentration of fish oil decreased as microalgae meal was inserted, and these were used in five different substitutions: 0, 25, 50, 75, and 100%. The treatments were carried out in triplicate, and after 49 days of cultivation, the zootechnical parameters and the composition of fatty acids in the animals’ muscles were analyzed. In zootechnical performance, the shrimp obtained an average final weight of 16.59 ± 0.3 g, and the growth was approximately 1.89 ± 0.30 g week−1. In addition, feed conversion was, on average, 1.47 ± 0.28, and survival was greater than 97%. However, no significant difference was observed in these parameters. Regardless of the levels of fish oil replacement by microalgae meal, the composition of fatty acids in the shrimp muscle was ensured, as well as their quantity within groups, such as n-3 and n-6 polyunsaturated fatty acids. Thus, with the results obtained in the present study, it is suggested that it is possible to formulate a high-performance diet without any ingredients of marine origin (fish oil or fish meal), contributing to aquaculture's sustainability.

Resumo: Os múltiplos usos dos ecossistemas aquáticos pela humanidade e a contínua interferência das suas atividades têm contribuído para o surgimento de florações de cianobactérias potencialmente tóxicas. Aqui, primeiramente criamos um banco de dados de ocorrências de floração de cianobactérias no Brasil por meio de uma revisão sistemática da literatura científica disponível em plataformas on-line (por exemplo, Web of Science, Catálogo de Teses da Capes). Em segundo lugar, realizamos modelos de nicho ecológico com dados de ocorrência obtidos a partir desses estudos para prever áreas climaticamente adequadas para as florações. Selecionamos 21 variáveis bioclimáticas como dados ambientais de entrada. Usamos cinco métodos de modelagem diferentes para no cenário climático atual: (1) Maxent; (2) Support Vector Machines; (3) Random Forest; (4) Maximum Likelihood e (5) Gaussian. Encontramos que o número de publicações sobre eventos de floração foi maior em 2009 com um declínio nos anos de 2012, 2013 e 2017. Além disso, os anos com os registros mais altos de florescimento em ambientes de água doce foram 2005, 2011 e 2014. Esses eventos ocorrem principalmente em reservatórios de abastecimento público e são na sua maioria dos gêneros Microcystis Lemmermann, 1907, Dolichospermum (Ralfs ex Bornet & Flahault) P.Wacklin, L.Hoffmann & J.Komárek, 2009 e Raphidiopsis F.E.Fritsch & F.Rich, 1929. Modelando a distribuição potencial das florações, encontramos lacunas de amostragem que devem ser direcionadas para futuras pesquisas, especialmente no bioma Amazônia. Em geral, os modelos não previram áreas altamente adequadas no norte do Brasil, enquanto outras regiões estavam relativamente bem distribuídas com um número maior de registros de ocorrência na região Sudeste.

Abstract: The multiple uses of aquatic ecosystems by humankind and the continuous interference of their activities have contributed to the emergence of potentially toxic cyanobacteria blooms. Here, we firstly created a database of occurrences of cyanobacteria blooms in Brazil through a systematic review of the scientific literature available in online platforms (e.g. Web of Science, Capes Thesis Catalogue). Secondly, we carried out ecological niche models with occurrence data obtained from these studies to predict climatically suitable areas for blooms. We select 21 bioclimatic variables input environmental data. We used five modeling methods for the current climate scenario: (1) Maxent; (2) Support Vector Machines; (3) Random Forest; (4) Maximum Likelihood e (5) Gaussian. We found that the number of publications about bloom events was higher in 2009 with a decline in the years 2012, 2013 and 2017. Furthermore, the years with the higher records of blooms in freshwater environments were 2005, 2011 e 2014. These events occurring mainly in public supply reservoirs and are mostly of the genera Microcystis Lemmermann, 1907, Dolichospermum (Ralfs ex Bornet & Flahault) P.Wacklin, L.Hoffmann & J.Komárek, 2009 and Raphidiopsis F.E.Fritsch & F.Rich, 1929. Modeling the potential distribution of blooms, we found sampling gaps that should be targeting for future researches, especially in the Amazon biome. Overall, the models did not predict highly suitable areas in the /north of Brazil, while other regions were relatively well distributed with a higher number of occurrence records in the Southeast region.

ABSTRACT The objective of this study was to evaluate the effect of different stocking densities and the presence/absence of two artificial substrates on water quality and production rates of marine shrimp in a biofloc shrimp nursery culture. Two experiments were performed: different stocking densities with mosquito netting substrate and the presence/absence of polyester-type substrate. The first experiment lasted 38 days, and shrimp at an initial weight of 0.013±0.010 g were stocked in 24 tanks. The second experiment lasted 35 days, and shrimp at an initial weight of 0.037±0.002 g were stocked in six tanks. Weekly biometric measurements were performed to adjust the amount of feed. Suspended solids were higher at a density of 6000 PL m−3 and mosquito netting substrate. Final weight and specific growth rate were higher in treatments with mosquito netting substrate. However, survival was significantly lower with this substrate. Yield was significantly higher at a density of 6000 PL m−3. Polyester-type substrate had no significant effect on production rates or variables of water quality. However, this substrate could reduce the production of sludge. The results indicate that it is possible to culture shrimp in nursery stage up to 6000 PL m−3 in a biofloc system.

Resumo O presente trabalho teve por objetivo avaliar o uso de um protocolo de avaliação rápida de rios (PAR) como ferramenta de Educação Ambiental (EA) no nível fundamental da educação básica. Para isso, foram desenvolvidas atividades de EA envolvendo estudantes do ensino fundamental de uma escola pública (Ipameri, GO, Brasil). As atividades contemplaram desde oficinas de monitoramento ambiental até a aplicação do PAR adaptado ao nível de escolaridade dos estudantes. Os resultados apontam que o PAR utilizado foi capaz de propiciar ou contribuir com a construção de valores sociais, conhecimentos, habilidades, atitudes e competências voltadas para a conservação ambiental dos recursos fluviais locais. Conclui-se, portanto, que o PAR utilizado constituiu instrumento passível de ser utilizado em projetos e programas de EA em escolas de nível fundamental, considerando sua potencialidade em promover em jovens estudantes a observação, sensibilização e apropriação de conceitos referentes ao funcionamento dos rios e sua preservação/conservação.

Abstract The aim of the present study is to assess the use of rapid assessment protocols (RAPs) of rivers as environmental education (EE) instruments in elementary schools. Therefore, EE activities were proposed to students from a Brazilian public elementary school. The activities included ranged from environmental-monitoring workshops to RAPs adapted to the level of schooling of the students. The students completed questionnaires before and after the activities in order to check their degree of knowledge prior to the activities and to assess the information acquired after participation in the activities. The results established that the RAP provided and/or helped to instill social values, knowledge, skills, actions, and competences linked to the environmental conservation of local rivers. The study therefore proves that the use of the RAP would be a valuable addition to EE projects and programs in elementary schools.

ABSTRACT This study evaluated the performance, immunology, and survival of the Pacific white shrimp Litopenaeus vannamei to experimental challenge to Vibrio alginolyticus based on the use of the probiotic Lactobacillus plantarum and the combined use of probiotic and butyrate. Four different diets resulted from the addition of additives: butyrate, probiotic, butyrate + probiotic, and control (no additives). The attractiveness of the diets was assessed by the percentage of positive choices and rejections, using a dual-choice Y-maze format aquarium. The shrimps were fed during four weeks and performance parameters, intestinal microbiota, and immunological parameters were all evaluated. Subsequently, the shrimps were challenged with V. alginolyticus and after 48 h, survival and immunological parameters were evaluated. The results showed increased attractiveness and intake, but only with diets supplemented with sodium butyrate. However, other diets were not rejected. No difference in performance or immunological parameters was observed among the different diets. Also, among the treatments, no difference in Vibrio spp., or total heterotrophic bacteria counts, was found in the intestinal tract. However, the lactic acid bacteria count was higher in the intestinal tract of shrimps fed diets supplemented with probiotic. After bacterial challenge, shrimp fed all diets had a greater survival when compared with the control group. Lactobacillus plantarum and sodium butyrate increase the resistance of shrimp to infection with V. alginolyticus, but do so without affecting performance, immunological parameters, or Vibrio spp., and total heterotrophic bacteria counts in the intestinal tract.

O presente estudo teve como objetivo adequar um protocolo de avaliação rápida de rios (PAR) para utilização por crianças do ensino fundamental. O estudo foi desenvolvido em Ipameri, GO e o PAR foi adequado para avaliação de riachos do bioma Cerrado do Sudeste goiano. A partir de dois protocolos referência (um nacional e outro oriundo dos EUA), o PAR adequado abrangeu: parâmetros físicos que condicionam o funcionamento dos riachos, linguagem adaptada ao nível de escolaridade do ensino fundamental e a presença de ilustrações esquemáticas que auxiliam a aplicação do PAR em campo pelos estudantes. Para a consolidação do instrumento desenvolvido, foi oferecida uma oficina de monitoramento a 95 estudantes de duas instituições públicas de ensino e realizada uma análise e interpretação do padrão de respostas obtidas na etapa prática da oficina. Os testes Bartlett e Levene não revelaram diferenças estatísticas entre o padrão de resposta dos estudantes, possibilitando inferir que o PAR desenvolvido mostra-se compreensível por parte dos avaliadores. A aplicação do PAR foi rápida (entre 20 e 40 minutos) e os alunos relataram que o instrumento desenvolvido os aproxima das questões ambientais, que a oficina de monitoramento os ajudou a compreender o instrumento e que as ilustrações disponíveis facilitaram a avalição em campo. Em adição, os estudantes afirmaram que se sentiram sensibilizados para com as questões ligadas à preservação dos recursos hídricos e disseram que a participação na oficina de monitoramento ambiental permitiu a apropriação de conhecimentos sobre o funcionamento dos sistemas fluviais. Conclui-se que o PAR adequado mostra-se como uma ferramenta útil e interessante para ser utilizada em projetos e programas de Educação Ambiental.

The present study aimed to adapt a rapid river assessment protocols (RAP) to be used by elementary school children. The study was conducted in Ipameri, GO and the RAP was adapted for the evaluation of streams in the Cerrado biome. Based on two protocol models, the developed RAP included: physical parameters that affect the functioning of streams, language adapted to the educational level of elementary school and the presence of drawings that could facilitate the field application of RAP by the students. For consolidation of the adapted instrument, it was offered a monitoring workshop to 95 students from two public education institutions, and developed an analysis and interpretation of the pattern of responses obtained during the practical step of the workshop. The Bartlett and Levene tests revealed no statistical differences between the response patterns of the students, allowing to infer that the developed RAP was understandable by the evaluators. The application of the RAP was fast (20 to 40 minutes) and the students reported that the developed instrument helped them to familiarize with environmental issues. In addition, the monitoring workshop helped them to understand the instrument and the available illustrations facilitated the field evaluation. In addition, the students concluded that they have become aware of the issues related to the water resource preservation and also that participation in the environmental monitoring workshop allowed the appropriation of knowledge about the river system functioning. It was concluded that adapted RAP has been proved to be a useful and interesting tool for using in environmental education projects and programs.