The growth, physiology and skin pigmentation of pacamã Lophiosilurus alexandri juveniles were evaluated in an experiment using different tank colours (white, yellow, green, blue, brown and black) over an 80 day period. The tank colours did not cause significant differences to final body mass, total length, survival rate, carcass composition (moisture, crude protein, ash, ether extract, calcium, phosphorus, energy), or to plasma protein, triglyceride and cholesterol values. Haematocrit values, however, were highest for fish kept in white tanks (ANOVA P < 0·05), while the greatest haemoglobin levels were recorded for fish kept in blue and brown tanks (P < 0·01). The concentrations of cortisol (P < 0·001) and glucose (P < 0·01) were the most in fish in the black tanks. Tank colour affected skin pigmentation significantly, with fish in white tanks having the highest values of L* (brightness) and the lowest values in blue and black tanks. L*, however, decreased in all treatments throughout the experiment. C* increased significantly over the course of the experiment in fish kept in white tanks. Similar increases of C* were recorded in the other treatments but to a lesser extent. The use of black tanks during the cultivation of L. alexandri caused stress and should be avoided. Cultivation in white and yellow tanks produced individuals with a pale skin colour, while cultivation in blue and black tanks resulted in juveniles with a darker and more pigmented skin.

Biofloc technology system (BFT), recirculation aquaculture system (RAS) and polyculture promote efficient use of water, area and nutrient recycling, which are essential practices for sustainable aquaculture development. The aim of this study was to evaluate the growth, feed efficiency, biofloc composition and water quality of Nile tilapia Oreochromis niloticus (Linnaeus, 1758) in monoculture and polyculture with giant freshwater prawn Macrobrachium rosenbergii (De Man, 1906) in BFT and RAS, over a period of 30 days. Fish (n = 128; 7.29 ± 0.67 g) were distributed randomly in 16 experimental tanks (8 fish/tank). Prawn (n = 96; 0.50 ± 0.09 g) were allocated in 8 experimental tanks (12 prawn/tank) in a polyculture. The experimental design was completely randomized with four treatments with four replicates each, in a factorial design 2 9 2 (BFT and RAS vs. monoculture and polyculture). The experimental diet (28% of digestible protein; 3100 kcal kg-1 of digestible energy) was used both to fish and prawn in BFT and RAS. There was significant effect (p \ 0.01) of the system and the culture for weight gain, apparent feed conversion and protein efficiency ratio. The average weight gain and apparent feed conversion of tilapia in monoculture (30.04 g and 1.39) and in polyculture (36.44 g and 1.27) were superior (p \ 0.01) in BFT than in monoculture (23.64 g and 1.74) and in polyculture (24.14 g and 1.61) in RAS. Weight gain and survival of giant freshwater prawn was superior (p \ 0.01) in BFT (0.43 g and 87%) compared to RAS (0.26 g and 79%). The data showed that BFT provides better growth performance responses in monoculture for Nile tilapia and in polyculture with giant freshwater prawn compared to RAS.

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Resumo -O objetivo deste trabalho foi avaliar o efeito de diferentes cores de tanques na larvicultura de Brycon orthotaenia, durante os primeiros dez dias de criação. Foram avaliados tanques de cores claras (branco, azul claro e verde claro) e escuras (marrom e preto). Como alimento, utilizaram-se larvas de Prochilodus costatus, até o quinto dia de alimentação, e a partir do terceiro dia foi também fornecida ração comercial com 55% de proteína bruta. Foram analisados: o crescimento, a sobrevivência e o fator de condição de Fulton. Aos cinco dias, tanto o peso como o comprimento total e a taxa de crescimento específi co (TCE) foram semelhantes entre os tratamentos. No entanto, aos dez dias, animais mantidos em tanques de cores escuras apresentaram menor peso e comprimento total, porém, com TCE semelhante apesar das diferentes cores de tanque. O fator de condição de Fulton, ao fi nal do experimento, foi menor nos animais mantidos em tanques escuros. A sobrevivência foi menor em tanques de cor preta, aos cinco e dez dias de criação. Os maiores valores foram registrados nos tanques de cores marrom, verde claro e branco. Tanques claros são recomendados para a larvicultura de B. orthotaenia, pelo melhor desempenho e sobrevivência dos animais.Termos para indexação: Brycon orthotaenia, alimentação, canibalismo, manejo. Matrinxã larviculture in tanks of different colorsAbstract -The objective of this work was to evaluate the effect of different color tanks on Brycon orthotaenia larviculture, during the fi rst ten days of rearing. Light color tanks (white, light blue and light green) and dark tanks (brown and black) were evaluated. The fi shes were fed with Prochilodus costatus larvae until the 5 th day and, from the 3 rd day on, commercial dry feed with 55% crude protein was also supplied. The growth, survival and Fulton's condition factor were evaluated. At fi ve days of feed, the weight, total length and specifi c growth rate (SGR) were similar among treatments. However, after ten days, the animals kept in dark tanks showed the lowest weight and total length; but the SGR was similar despite the different color tanks. The Fulton's condition factor, observed at the end of the experiment, was lower in animals reared in dark tanks. The survival was lower in black tanks, at fi ve and ten days of rearing. The best survival, at the end of the experiment, was observed in brown, light green and white tanks. Light tanks are recommended for B. orthotaenia larviculture, for animals' best development and survival.

ABSTRACT:The goal of this study was to develop a fuzzy model to predict the occupancy rate of free-stalls facilities of dairy cattle, aiding to optimize the design of projects. The following input variables were defined for the development of the fuzzy system: dry bulb temperature (T db , °C), wet bulb temperature (T wb , °C) and black globe temperature (T bg , °C). Based on the input variables, the fuzzy system predicts the occupancy rate (OR, %) of dairy cattle in free-stall barns. For the model validation, data collecting were conducted on the facilities of the Intensive System of Milk Production (SIPL), in the Dairy Cattle National Research Center (CNPGL) of Embrapa. The OR values, estimated by the fuzzy system, presented values of average standard deviation of 3.93%, indicating low rate of errors in the simulation. Simulated and measured results were statistically equal (P>0.05, t Test). After validating the proposed model, the average percentage of correct answers for the simulated data was 89.7%. Therefore, the fuzzy system developed for the occupancy rate prediction of free-stalls facilities for dairy cattle allowed a realistic prediction of stalls occupancy rate, allowing the planning and design of free-stall barns. KEYWORDS:Confinement systems, bovine facilities, design, stalls, dairy cattle. PREDIÇÃO DA TAXA DE OCUPAÇÃO DE BAIAS EM INSTALAÇÕES TIPO FREE-STALL PARA BOVINOS DE LEITE POR MEIO DOS CONJUNTOS FUZZY RESUMO:Objetivou-se com o presente trabalho desenvolver um modelo fuzzy para predizer a taxa de ocupação de baias em instalações para gado de leite do tipo free-stall, auxiliando na otimização do dimensionamento de projetos. Para o desenvolvimento do sistema fuzzy, foram definidas como variáveis de entrada: a temperatura de bulbo seco (T bs , °C); temperatura de bulbo úmido (T bu , °C), e temperatura de globo negro (T gn ,ºC). Com base nas variáveis de entrada, o sistema fuzzy prediz a taxa de ocupação (TO,%) de vacas leiteiras em instalações do tipo free-stall. Para a validação do modelo, coletas de dados foram realizadas nas instalações do Sistema Intensivo de Produção de Leite (SIPL), do Centro Nacional de Pesquisa de Gado de Leite (CNPGL) da Embrapa. Os valores de TO estimados pelo sistema fuzzy apresentaram valores de desvio-padrão médio de 3,93%, indicando baixo índice de erros na simulação. Os resultados simulados foram, estatisticamente, iguais aos medidos (P>0,05, Teste t). Após a validação do modelo proposto, a porcentagem de acerto médio para os dados simulados foi de 89,7%. Portanto, o sistema fuzzy, desenvolvido para a predição da taxa de ocupação de baias em instalação free-stall para bovinos leiteiros, possibilitou a predição realística da taxa de ocupação de baias, propiciando o planejamento e o projeto de instalações free-stall. PALAVRAS-CHAVE:Sistema de confinamento, instalações para bovinos, projeto, baias, vacas leiteiras.

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The present study investigated the effects of salinity on growth, mortality, gill morphology and muscle cellularity in Lophiosilurus alexandri. Fish were submitted to the following salinity for 28 days: 0 (S0), 2.5 (S2.5), 5.0 (S5), 7.5 (S7.7) and 10 (S10) ppt. Growth and protein efficiency ratio (PER) decreased with the increase of salinity. All fish from S10 died between the 16th and 21st day of the experiment. Mortality in S7.5 was 78% at the end of 28 days of salinity exposure. Increased salinity was accompanied by increased vascular congestion, hyperplasia of gill filament epithelium, lamellar fusion and loss of structural integrity of pillar cells. Fish at S2.5 and S5 had higher mucosal cell hyperplasia. Chloride cell quantity was higher in fish in the S2.5 to S7.5. In general, L. alexandri juvenile exposed to treatments of freshwater and S2.5 had similar patterns of muscle cellularity, with high averages for the most of the variables of muscle cellularity evaluated. The large fibre size classes tended to decrease with increasing salinity. L. alexandri juveniles may be cultivated up to 2.5 g of salt/L, and superior concentrations change growth, induce damage to gills and modify muscle cellularity.

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