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Neu D.H.,State University of Maringa | Furuya W.M.,State University of Ponta Grossa | Furuya W.M.,Brazilian National Council for Scientific and Technological Development | Boscolo W.R.,West Parana State University | And 5 more authors.
Revista Brasileirade Ciencias Agrarias

Glycerol is a biodiesel industry byproduct and it can provide energy for animals when included in diets. This study was carried out to determine the digestible energy values of different sources of glycerol for Nile tilapia. Forty fish weighing, in average, 343.1 ± 77.7 g were distributed in four 180 liter tanks with a conned bottom, in a randomized Latin Square Design. Four experimental diets were prepared: one reference and three test diets containing 20% of the test meal and 80% of the reference diet. Chromic oxideIII was used as indicator (0.1% diet). The glycerol sources evaluated were: crude vegetable oil glycerol (GBV); semi-purified mixture glycerol (GSM); and semi-purified vegetable glycerol (GSV), in which the digestible energy values of 3058; 2610 and 1754 kcal kg-1 were obtained, respectively, without differences between the digestible energy of glycerol GBV and GSM, which were higher than GSV. Source

Freire K.M.F.,Federal University of Sergipe | Machado M.L.,Ministerio da Pesca e Aquicultura | Crepaldi D.,Nucleo de Ecossistemas Aquaticos

This article presents a general overview of recreational fisheries in Brazil, with emphasis on inland fisheries; reports their current needs; and provides directions for future work considering that there is an apparent increase in recreational fishing in emerging economies around the globe. Even though there is no nationwide survey to identify the profile of all Brazilian recreational fishers, some insights can be obtained from competitive fishing events and from the questionnaire printed on the back of fishing licenses. The number of fishing licenses issued in 2010 was approximately 220,000, representing an increase of 220% compared to 2000. Some estimates suggest that the number of recreational fishers in Brazil may be around 10 million. Information on fishing expenses, catchand-release activities, fishing guides, lodging, fishing areas, target species, management control, and fishing clubs and associations is presented. Data for basic estimates such as total number of recreational fishers, total catch and species composition, and total economic value are unavailable, but the results presented here are nevertheless essential for a long-term planning of the development of recreational fishing in Brazil. Other requirements are presented and suggestions are made toward improved management of recreational fisheries in Brazil and other emerging economies. Source

Sanches E.A.,Pos Graduando CAUNESP | Neumann G.,West Parana State University | Baggio D.M.,Ministerio da Pesca e Aquicultura | Bombardelli R.A.,West Parana State University | And 2 more authors.

The objective of this study was to evaluate the effects of three water and storage temperatures on the oocytes of the jundiá catfish, Rhamdia quelen. A factorial experimental design over time, with treatments completed in triplicate every 48 h, was used (5 × 3 × 3 × 3) to study the exposure of the oocytes to temperatures of 15, 25 and 35. °C and activated with water at 15, 25 and 35. °C each at 0, 45, 90, 135 and 180 minutes post-collection. Linear regression analysis for the response surface model indicated an interaction (p<0.05) between time and temperature of exposure with greater values for fertilization, hatching and normal larvae rates at the time of oocyte collection (70.2 ± 8.4% fertilized oocytes, 66.7 ± 29.4% hatched eggs and 30.3 ± 25.0% normal larvae). According to the statistical model, the water temperature that resulted in the highest fertilization rate was 25.6. °C (p<0.05). The rates of fertilization, hatching and normal larvae correlated positively (p<0.05) with one another, showing that these parameters can be used in the measurement of oocyte quality. Artificial fertilization of oocytes is recommended immediately after collection; if storage is necessary, it should be carried out at 15. °C. © 2011 Elsevier B.V. Source

Mignani L.,Ministerio da Pesca e Aquicultura | Barbieri E.,Institute Pesca | Almeida Marques H.L.,Institute Pesca | Cardoso de Oliveira A.J.F.,Sao Paulo State University
Pesquisa Agropecuaria Brasileira

The objective of this work was to evaluate the total and thermotolerant coliform densities in the oyster culture water of Cananeia, SP, Brazil, correlating these densities with environmental variables and tidal variations. Superficial water samples were collected in two tide conditions (spring and neap) from three areas of Cananéia municipality (Mandira, Itapitangui and Cooperostra). The three studied areas showed good conditions for the culture regarding coliform densities. The two tidal conditions differed significantly as to total coliform concentration; however, the same procedure was not performed for thermotolerant coliforms. No correlation was observed between water temperature, pH, and concentrations of total and thermotolerant coliforms. Coliform density was positively correlated with rainfall and negatively correlated with salinity. Spring and neap tides differed significantly as to coliform number. Simple diagnosis of environmental conditions of the crop fields is insufficient to assess water quality of shellfish cultivation. A continuous monitoring program of planted areas is necessary both for the assessment of water quality potential for marine culture and for ensuring safe consumption of seafood, besides constituting an important tool to understand the relationships between contamination and the involved environmental variables. Source

Jimenez E.A.,Federal University of Para | Filho M.A.,Ministerio da Pesca e Aquicultura | Fredou F.L.,University of Pernambuco
Brazilian Journal of Oceanography

This study aimed to analyse the composition and seasonal variation in the fish bycatch of the Brachyplatystoma vaillantii trawl fishery in the Amazon Estuary in 2009 by monitoring the trips of 48 vessels. The bycatch represented 29% of the catches, totalling 22,228 specimens and 52 taxa, distributed in 22 families (the principal families were Ariidae, Pimelodidae, and Sciaenidae). Brachyplatystoma rousseauxii, Plagioscion squamosissimus, and Sciades herzbergii together contributed 69% of the bycatch and were considered consistent bycatch species. Although a higher proportion of bycatch was captured during the rainy season, the seasonal difference was not significant. A multidimensional scaling (MDS) ordination analysis and an analysis of similarity (ANOSIM) indicated that the species composition of the bycatch was similar across the seasons. However, larger numbers of B. rousseauxii and P. squamosissimus were captured during the rainy season, whereas S. herzbergii predominated during the dry season. The marine migrants and estuarine species guilds showed the greatest richness, whereas freshwater migrants were the most numerous. Among the feeding guilds, the zoobenthivores were the most diverse, whereas the piscivores were the most abundant. The results indicate that fishing pressure primarily affects small- (20-30 cm) and medium-sized (30-50 cm) individuals, although the catch of P. squamosissimus was composed primarily of adults. However, the catches of both B. rousseauxii and B. vaillantii were composed primarily of juveniles. Source

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