Wagner Valenti | Universidade Estadual Paulista "Júlio de Mesquita Filho" (original) (raw)

Papers by Wagner Valenti

Research paper thumbnail of ASSESSING THE POTENTIAL OF PARTIAL REPLACING OF Artemia BY PRACTICAL INERT DIET IN THE LARVICULTURE OF THE AMAZON RIVER PRAWN

Boletim Do Instituto De Pesca, 2014

The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcust... more The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcustard in the final phase of Macrabrachium amazonicum hatchery. The treatments were: AN-IX – larvae were fed Artemia nauplii during all culture and when they reached stage V, inert diet was added to the feed (control); AN-VII – larvae were fed Artemia nauplii from stage II to stage VI and it was totally replaced by inert diet from stage VII onwards; AN-V – larvae were fed Artemia nauplii from stage II to stage IV and it was totally replaced by inert diet from stage V onwards. Larvae were reared in 120-L culture tanks, coupled to biological filters. Larvae largely ingested inert diet when it was the single food available (90-100% of animals showed digestive tract full). Nonetheless, feeding larvae of M. amazonicum with solely inert diet from stage V or VII onward, negatively affect larval development and survival. Productivity drastically decreased from ~60 PL L-1 (control) to ~40 PL L-1 in ...

Research paper thumbnail of ECONOMIC ANALYSIS of AMAZON RIVER PRAWN FARMING TO THE MARKETS FOR LIVE BAIT and JUVENILES IN PANTANAL, BRAZIL

Boletim Do Instituto De Pesca, 2011

The implementation of a hypothetical aquaculture facility with hatchery, nursery and grow-out ear... more The implementation of a hypothetical aquaculture facility with hatchery, nursery and grow-out earthen ponds for raising the Amazon River Prawn Macrobrachium amazonicum in the Pantanal was considered. Eight larviculture cycles per year were projected: four to produce post-larvae for stocking in grow-out bait ponds, and four to stock nursery tanks to sell juveniles as seed to growout farms, which produce prawns for human consumption. Annual production would be 146,880 dozen bait prawns and 2,938 thousand juveniles. The assumed sale prices were US$ 1.38 per dozen baits and US$ 15.39 per thousand juveniles. The net present value was US$ 555,890.79, internal rate of return was 48% per year, payback period was 2.4 years and benefit-cost ratio was 3.90. The breakeven price to cover total costs per dozen baits was US$ 0.70 and per thousand juveniles was US$ 17.00, indicating that the selling price assumed for juveniles in base scenario is not realistic. Net return was US$ 84,773.80. The res...

Research paper thumbnail of Sustainability Analysis of the Production of Early Stages of the Atlantic Forest Lambari (Deuterodon iguape) in a Public Hatchery at a Rainforest Conservation Area

Sustainability

Protected areas have been used worldwide to conserve natural resources. Nevertheless, economic ac... more Protected areas have been used worldwide to conserve natural resources. Nevertheless, economic activities to provide income for communities living within and surrounded by conservation areas remain an issue. This study aimed to assess the sustainability of a Deuterodon iguape hatchery, situated within an Atlantic Rainforest Park, to leverage grow-out farming of this small native fish, affording income and food security for local families. We have used a set of indicators of economic, social, and environmental sustainability. The initial investment is about US$ 40,000, which should see a return in ~2 years. The internal rate of return is close to 50%, including the externality costs, which is attractive for both public and private investors. The hatchery generated few direct jobs, but the workforce can be recruited from the community, and the hatchery can enable the establishment of several small grow-out farms, leveraging the development of indirect jobs and self-employment. The sys...

Research paper thumbnail of Improving the Efficiency of Production of Lambari and Diet Assimilation Using Integrated Aquaculture With Benthic Species

A single farmed fish species assimilate about 20% of the nutrients in the supplied diet. This stu... more A single farmed fish species assimilate about 20% of the nutrients in the supplied diet. This study evaluated if the culture of complementary ecological-function species can recover nutrients dispersed into the water and transform them into high-valued biomass. A completely randomized experiment was designed with three treatments and four replications of each production system: monoculture of lambari (Astyanax lacustris); integrated aquaculture of lambari and Amazon river prawn (Macrobrachium amazonicum); and integrated aquaculture of lambari, Amazon river prawn, and curimbatá (Prochilodus lineatus). Fingerlings of lambari (0.8 ± 0.8 g) were stocked in twelve earthen-ponds (0.015 ha) at the density of 50 fish m-2. Eight ponds, were stocked with juveniles of Amazon river prawn (1.1 ± 0.2 g) at the density of 25 prawn m−2. Four of these eight ponds were stocked with curimbatá fingerlings (0.2 ± 0.1 g) at a density of 13 fish m-². Only lambari was fed twice a day with an extruded comme...

Research paper thumbnail of Technical and economic feasibility of integrating seahorse culture in shrimp/oyster farms

Aquaculture Research, 2015

Integrated multi-trophic aquaculture systems (IMTA) are building ecosystems designed to produce a... more Integrated multi-trophic aquaculture systems (IMTA) are building ecosystems designed to produce aquatic organisms with less environmental impact. We have developed a simple system and a management strategy for introducing seahorse (Hippocampus spp.) culture in shrimp/oyster farms to increase economic sustainability. The system includes broodstock, nursery and grow-out phases of Hippocampus reidi G. culture. We performed a test in a 42.4-ha marine shrimp/oyster farm, which showed that this system is technically feasible. Then, we performed a partial budget analysis including cost-return, cash flow and financial feasibility analysis. More than 12 000 marketable size seahorses may be produced in 402 m 2 annually. Initial investment was only US$ 21 103.00. The benefit-cost ratio was~US$ 20.00 for each US$ 1.00 spent, internal rate of return was 131% and payback period <2 years. In conclusion, the introduction of seahorse in shrimp/oyster IMTA system is technically feasible, profitable, resilient and shows high liquidity. This system may be easily established in developing countries and has potential to provide seahorses to supply different markets (live specimens for the marine aquarium trade and dried specimens for traditional Chinese medicine and the curio trade). In addition, it can indirectly contribute to preserve natural populations.

Research paper thumbnail of Integrated Freshwater Prawn Farming: State-of-the-Art and Future Potential

Reviews in Fisheries Science & Aquaculture, 2016

Integrated aquaculture can be defined as aquaculture systems sharing resources with other activit... more Integrated aquaculture can be defined as aquaculture systems sharing resources with other activities, commonly agricultural, agroindustrial, and infrastructural. Freshwater prawns are excellent options for integration, since they are omnivores and can therefore take advantage of a wide range of feed residuals, either from aquatic or terrestrial species. Furthermore, due to their benthic habit, they have a well-defined spatial distribution in the environment, thus favoring interaction with various species of fish, other animals, and even with plants. The integrated farming of freshwater prawns includes different culture systems, such as polyculture and coculture with other aquatic species, rice-prawn culture, hydroponics, and integration with terrestrial animals and plants. Our review includes a worldwide perspective on the main commercial integrated systems involving freshwater prawns, the present status of research on integrated freshwater prawn production and the main opportunities for integrated freshwater prawn farming in a world that is moving toward sustainability. The review continues by providing a brief summary of the future prospects for this form of aquaculture. Finally, we conclude that integrating freshwater prawn farming with other aquaculture and farming activities has considerable potential as a means of increasing food production in a sustainable fashion.

Research paper thumbnail of Population structure and growth of the hermit crab Pagurus brevidactylus (Anomura: Paguridae) from the northern coast of São Paulo, Brazil

The hermit crab Pagurus brevidactylus (Crustacea: Anomura: Paguridea) from the infralittoral area... more The hermit crab Pagurus brevidactylus (Crustacea: Anomura: Paguridea) from the infralittoral area of Anchieta Island, Ubatuba, was characterized by population structure (size, sex ratio, reproduction and recruitment) and growth. Animals were collected monthly during 1999 by SCUBA diving. A total of 1525 individuals was collected (633 males and 892 females), 695 of them were ovigerous females. Overall sex ratio was 0.7:1 in favour of females. The crabs showed a unimodal distribution with males signi¢cantly larger than females. Ovigerous females were collected during all months and in high percentages from 1.0 mm of shield length, demonstrating intense and continuous reproduction. The longevity was approximately 24 months for males and 18 for females, which showed larger growth rate and reached sexual maturity earlier (two months) than males. The low number of males in this population may be due to the longer life span. Moreover, the sexual dimorphism favours males during the intra-and interspeci¢c ¢ghts by shell, food, reproduction and territory. Females demonstrated a short life cycle and intense reproduction.

Research paper thumbnail of Improving the Efficiency of Lambari Production and Diet Assimilation Using Integrated Aquaculture with Benthic Species

Sustainability

A single farmed fish species assimilates about 20% of the nutrients in the supplied diet. This st... more A single farmed fish species assimilates about 20% of the nutrients in the supplied diet. This study evaluated if the culture of complementary ecological-function species can recover nutrients dispersed into water and transform them into high-valued biomass. A completely randomized experiment was designed with three treatments and four replications of each production system: monoculture of lambari (Astyanax lacustris); integrated aquaculture of lambari and Amazon river prawn (Macrobrachium amazonicum); and integrated aquaculture of lambari, Amazon river prawn, and curimbatá (Prochilodus lineatus). Fingerlings of lambari (0.8 ± 0.8 g) were stocked in twelve earthen-ponds (0.015 ha) at the density of 50 fish m−2. Eight ponds were stocked with juveniles of Amazon river prawn (1.1 ± 0.2 g) at the density of 25 prawn m−2. Four of these eight ponds were stocked with curimbatá fingerlings (0.2 ± 0.1 g) at a density of 13 fish m−2. Only lambari was fed twice a day with an extruded commercia...

Research paper thumbnail of A bioeconomic analysis of the potential of seaweed Hypnea pseudomusciformis farming to different targeted markets

Aquaculture Economics & Management

Research paper thumbnail of The effect of choice of targeted market, production scale, and land tenure on the economics of integrated tilapia-prawn production

Aquaculture Economics & Management

Integrated aquaculture systems have the potential to enhance the environmental sustainability of ... more Integrated aquaculture systems have the potential to enhance the environmental sustainability of aquaculture production, if economically feasible. Data from integrated tilapia-prawn production trials were used to develop economic-engineering enterprise budgets for ponds with and without substrate that targeted two different types of markets, using two production scales and two forms of land tenure. Inclusion of substrate increased investment and fixed costs and decreased net returns. Recreational markets (live tilapia for fee fishing and live prawns as bait) were profitable, but sales to supermarkets were not. Production scale and land tenure affected economic outcomes with increased pond size and leasing ponds demonstrating greater profitability. Results provide evidence of the need to carefully evaluate economic trade-offs associated with varying commercial-scale applications to increase the likelihood of adoption of new technologies.

Research paper thumbnail of Chemical Profile of the Sulphated Saponins from the Starfish Luidia senegalensis Collected as by-Catch Fauna in Brazilian Coast

Natural products and bioprospecting, Jan 22, 2018

The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are disca... more The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are discarded because they do not have commercial value. In order to try to add some value to these materials, we analyzed the chemical composition of the starfish Luidia senegalensis collected in the Brazilian coast as a consequence of the trawling fishery method. In order to access their chemical composition, we used a combination of solid phase extraction (SPE) followed by ultra-high performance liquid chromatography coupled to electrospray ionization ion trap tandem mass spectrometry (UPLC-ESI-IT-MS). Luidia senegalensis contains asterosaponins, which are sulphated glycosilated steroids, containing five and six sugar moieties, in addition to polyhydroxysteroids. This study helped us to support the presence of important and potentially bioactive compounds in invertebrates associated to the by-catch fauna of the shrimp fishery, using a fast and efficient method.

Research paper thumbnail of Concentrações de amônia, nitrito e nitrato em larvicultura do camarão <em>Macrobrachium rosenbergii</em> (De Man), realizada em sistema fechado com água salobra natural e artificial

Acta Scientiarum. Animal Sciences

RESUMO. Avaliou-se o efeito da água salobra natural e artificial e da sua utilização em dois cult... more RESUMO. Avaliou-se o efeito da água salobra natural e artificial e da sua utilização em dois cultivos consecutivos sobre as concentrações de amônia, nitrito e nitrato, em sistema fechado de larvicultura de M. rosenbergii (Crustacea, Decapoda). A amônia oscilou entre 1,1 e 74,0 µg/l e o nitrito entre e 1,1 e 34,6 µg/l; estes não diferiram entre os tipos de água analisados. A concentração de nitrato (N) aumentou ao longo do tempo (T) de forma similar na água natural e artificial, seguindo um modelo linear (N = 0,241T-0,734). Os resultados indicaram que a água salobra artificial não alterou o processo de nitrificação, tampouco o comportamento das principais variáveis ambientais. A reutilização da água também não produziu nenhum efeito negativo sobre essas variáveis. A fórmula de água do mar artificial aqui apresentada pode ser, portanto usada em sistemas de recirculação para a produção de pós-larvas de M. rosenbergii em até dois cultivos consecutivos.

Research paper thumbnail of Successful invasion of the Amazon Coast by the giant river prawn, Macrobrachium rosenbergii: evidence of a reproductively viable population

Research paper thumbnail of Economics and Management of Freshwater Prawn Culture in Western Hemisphere

Shrimp Culture, 2006

... A comprehensive sum-mary of M. rosenbergii economics around the world through the year 2000 i... more ... A comprehensive sum-mary of M. rosenbergii economics around the world through the year 2000 is provided by Rhodes (2000). ... Grow-out phase in temperate regions is presented in Tidwell and D&#x27;Abramo (2000), while grow-out phase in subtropical and tropical regions is ...

Research paper thumbnail of Intensification of the Giant river prawn Macrobrachium rosenbergii hatchery production

Aquaculture Research, 2015

Research paper thumbnail of Effect of tank colour on larval performance of the Amazon River prawn Macrobrachium amazonicum

Aquaculture Research, 2012

The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcust... more The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcustard in the final phase of Macrabrachium amazonicum hatchery. The treatments were: AN-IXlarvae were fed Artemia nauplii during all culture and when they reached stage V, inert diet was added to the feed (control); AN-VIIlarvae were fed Artemia nauplii from stage II to stage VI and it was totally replaced by inert diet from stage VII onwards; AN-Vlarvae were fed Artemia nauplii from stage II to stage IV and it was totally replaced by inert diet from stage V onwards. Larvae were reared in 120-L culture tanks, coupled to biological filters. Larvae largely ingested inert diet when it was the single food available (90-100% of animals showed digestive tract full). Nonetheless, feeding larvae of M.

Research paper thumbnail of Toward a good scientific writing

International Aquatic Research, 2014

Some editors point to the ''lack of style'' as a major deficiency of the manuscripts submitted fo... more Some editors point to the ''lack of style'' as a major deficiency of the manuscripts submitted for publication. Producing an adequate text is an arduous and time-consuming task, even for those who have mastered the scientific language. We should revise what we wrote many times to achieve an acceptable product. Scientific language should be clear, objective, written in proper sequence, with short sentences and long paragraphs. The following points are some practical guidelines to start writing in a good scientific style.

Research paper thumbnail of Measuring sustainability in aquaculture systems

Research paper thumbnail of Freshwater prawns

Research paper thumbnail of Impact of maintenance of Macrobrachium rosenbergii De Man, 1879 (Crustacea, Decapoda, Palaemonidae) broodstock on the water used in culture ponds

Brazilian Journal of Biology, 2011

Aquaculture production generates social and economic benefits, but can also cause environmental i... more Aquaculture production generates social and economic benefits, but can also cause environmental impacts. The objectives of this study were: a) to characterise the impacts caused by the maintenance of broodstock of the giant river prawn (Macrobrachium rosenbergii) on the physical and chemical characteristics of the water used in culture ponds, and b) to evaluate the relationship between the biomass of the prawns and the impact of culture on the water used in the ponds. Between January and December 2004, we determined, monthly, the biomass of M. rosenbergii by means of biometrics, and the physical and chemical variables of the supply and effluent water from a pond used to maintain breeding stock. The results showed that the effluent water had higher contents of chlorophyll-a, suspended particulate matter (SPM), pH, dissolved oxygen, total Kjeldahl nitrogen (TKN) and dissolved Kjeldahl nitrogen (DKN), inorganic nitrogen (IN), total (TP) and dissolved phosphorus (DP), and P-orthophospha...

Research paper thumbnail of ASSESSING THE POTENTIAL OF PARTIAL REPLACING OF Artemia BY PRACTICAL INERT DIET IN THE LARVICULTURE OF THE AMAZON RIVER PRAWN

Boletim Do Instituto De Pesca, 2014

The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcust... more The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcustard in the final phase of Macrabrachium amazonicum hatchery. The treatments were: AN-IX – larvae were fed Artemia nauplii during all culture and when they reached stage V, inert diet was added to the feed (control); AN-VII – larvae were fed Artemia nauplii from stage II to stage VI and it was totally replaced by inert diet from stage VII onwards; AN-V – larvae were fed Artemia nauplii from stage II to stage IV and it was totally replaced by inert diet from stage V onwards. Larvae were reared in 120-L culture tanks, coupled to biological filters. Larvae largely ingested inert diet when it was the single food available (90-100% of animals showed digestive tract full). Nonetheless, feeding larvae of M. amazonicum with solely inert diet from stage V or VII onward, negatively affect larval development and survival. Productivity drastically decreased from ~60 PL L-1 (control) to ~40 PL L-1 in ...

Research paper thumbnail of ECONOMIC ANALYSIS of AMAZON RIVER PRAWN FARMING TO THE MARKETS FOR LIVE BAIT and JUVENILES IN PANTANAL, BRAZIL

Boletim Do Instituto De Pesca, 2011

The implementation of a hypothetical aquaculture facility with hatchery, nursery and grow-out ear... more The implementation of a hypothetical aquaculture facility with hatchery, nursery and grow-out earthen ponds for raising the Amazon River Prawn Macrobrachium amazonicum in the Pantanal was considered. Eight larviculture cycles per year were projected: four to produce post-larvae for stocking in grow-out bait ponds, and four to stock nursery tanks to sell juveniles as seed to growout farms, which produce prawns for human consumption. Annual production would be 146,880 dozen bait prawns and 2,938 thousand juveniles. The assumed sale prices were US$ 1.38 per dozen baits and US$ 15.39 per thousand juveniles. The net present value was US$ 555,890.79, internal rate of return was 48% per year, payback period was 2.4 years and benefit-cost ratio was 3.90. The breakeven price to cover total costs per dozen baits was US$ 0.70 and per thousand juveniles was US$ 17.00, indicating that the selling price assumed for juveniles in base scenario is not realistic. Net return was US$ 84,773.80. The res...

Research paper thumbnail of Sustainability Analysis of the Production of Early Stages of the Atlantic Forest Lambari (Deuterodon iguape) in a Public Hatchery at a Rainforest Conservation Area

Sustainability

Protected areas have been used worldwide to conserve natural resources. Nevertheless, economic ac... more Protected areas have been used worldwide to conserve natural resources. Nevertheless, economic activities to provide income for communities living within and surrounded by conservation areas remain an issue. This study aimed to assess the sustainability of a Deuterodon iguape hatchery, situated within an Atlantic Rainforest Park, to leverage grow-out farming of this small native fish, affording income and food security for local families. We have used a set of indicators of economic, social, and environmental sustainability. The initial investment is about US$ 40,000, which should see a return in ~2 years. The internal rate of return is close to 50%, including the externality costs, which is attractive for both public and private investors. The hatchery generated few direct jobs, but the workforce can be recruited from the community, and the hatchery can enable the establishment of several small grow-out farms, leveraging the development of indirect jobs and self-employment. The sys...

Research paper thumbnail of Improving the Efficiency of Production of Lambari and Diet Assimilation Using Integrated Aquaculture With Benthic Species

A single farmed fish species assimilate about 20% of the nutrients in the supplied diet. This stu... more A single farmed fish species assimilate about 20% of the nutrients in the supplied diet. This study evaluated if the culture of complementary ecological-function species can recover nutrients dispersed into the water and transform them into high-valued biomass. A completely randomized experiment was designed with three treatments and four replications of each production system: monoculture of lambari (Astyanax lacustris); integrated aquaculture of lambari and Amazon river prawn (Macrobrachium amazonicum); and integrated aquaculture of lambari, Amazon river prawn, and curimbatá (Prochilodus lineatus). Fingerlings of lambari (0.8 ± 0.8 g) were stocked in twelve earthen-ponds (0.015 ha) at the density of 50 fish m-2. Eight ponds, were stocked with juveniles of Amazon river prawn (1.1 ± 0.2 g) at the density of 25 prawn m−2. Four of these eight ponds were stocked with curimbatá fingerlings (0.2 ± 0.1 g) at a density of 13 fish m-². Only lambari was fed twice a day with an extruded comme...

Research paper thumbnail of Technical and economic feasibility of integrating seahorse culture in shrimp/oyster farms

Aquaculture Research, 2015

Integrated multi-trophic aquaculture systems (IMTA) are building ecosystems designed to produce a... more Integrated multi-trophic aquaculture systems (IMTA) are building ecosystems designed to produce aquatic organisms with less environmental impact. We have developed a simple system and a management strategy for introducing seahorse (Hippocampus spp.) culture in shrimp/oyster farms to increase economic sustainability. The system includes broodstock, nursery and grow-out phases of Hippocampus reidi G. culture. We performed a test in a 42.4-ha marine shrimp/oyster farm, which showed that this system is technically feasible. Then, we performed a partial budget analysis including cost-return, cash flow and financial feasibility analysis. More than 12 000 marketable size seahorses may be produced in 402 m 2 annually. Initial investment was only US$ 21 103.00. The benefit-cost ratio was~US$ 20.00 for each US$ 1.00 spent, internal rate of return was 131% and payback period <2 years. In conclusion, the introduction of seahorse in shrimp/oyster IMTA system is technically feasible, profitable, resilient and shows high liquidity. This system may be easily established in developing countries and has potential to provide seahorses to supply different markets (live specimens for the marine aquarium trade and dried specimens for traditional Chinese medicine and the curio trade). In addition, it can indirectly contribute to preserve natural populations.

Research paper thumbnail of Integrated Freshwater Prawn Farming: State-of-the-Art and Future Potential

Reviews in Fisheries Science & Aquaculture, 2016

Integrated aquaculture can be defined as aquaculture systems sharing resources with other activit... more Integrated aquaculture can be defined as aquaculture systems sharing resources with other activities, commonly agricultural, agroindustrial, and infrastructural. Freshwater prawns are excellent options for integration, since they are omnivores and can therefore take advantage of a wide range of feed residuals, either from aquatic or terrestrial species. Furthermore, due to their benthic habit, they have a well-defined spatial distribution in the environment, thus favoring interaction with various species of fish, other animals, and even with plants. The integrated farming of freshwater prawns includes different culture systems, such as polyculture and coculture with other aquatic species, rice-prawn culture, hydroponics, and integration with terrestrial animals and plants. Our review includes a worldwide perspective on the main commercial integrated systems involving freshwater prawns, the present status of research on integrated freshwater prawn production and the main opportunities for integrated freshwater prawn farming in a world that is moving toward sustainability. The review continues by providing a brief summary of the future prospects for this form of aquaculture. Finally, we conclude that integrating freshwater prawn farming with other aquaculture and farming activities has considerable potential as a means of increasing food production in a sustainable fashion.

Research paper thumbnail of Population structure and growth of the hermit crab Pagurus brevidactylus (Anomura: Paguridae) from the northern coast of São Paulo, Brazil

The hermit crab Pagurus brevidactylus (Crustacea: Anomura: Paguridea) from the infralittoral area... more The hermit crab Pagurus brevidactylus (Crustacea: Anomura: Paguridea) from the infralittoral area of Anchieta Island, Ubatuba, was characterized by population structure (size, sex ratio, reproduction and recruitment) and growth. Animals were collected monthly during 1999 by SCUBA diving. A total of 1525 individuals was collected (633 males and 892 females), 695 of them were ovigerous females. Overall sex ratio was 0.7:1 in favour of females. The crabs showed a unimodal distribution with males signi¢cantly larger than females. Ovigerous females were collected during all months and in high percentages from 1.0 mm of shield length, demonstrating intense and continuous reproduction. The longevity was approximately 24 months for males and 18 for females, which showed larger growth rate and reached sexual maturity earlier (two months) than males. The low number of males in this population may be due to the longer life span. Moreover, the sexual dimorphism favours males during the intra-and interspeci¢c ¢ghts by shell, food, reproduction and territory. Females demonstrated a short life cycle and intense reproduction.

Research paper thumbnail of Improving the Efficiency of Lambari Production and Diet Assimilation Using Integrated Aquaculture with Benthic Species

Sustainability

A single farmed fish species assimilates about 20% of the nutrients in the supplied diet. This st... more A single farmed fish species assimilates about 20% of the nutrients in the supplied diet. This study evaluated if the culture of complementary ecological-function species can recover nutrients dispersed into water and transform them into high-valued biomass. A completely randomized experiment was designed with three treatments and four replications of each production system: monoculture of lambari (Astyanax lacustris); integrated aquaculture of lambari and Amazon river prawn (Macrobrachium amazonicum); and integrated aquaculture of lambari, Amazon river prawn, and curimbatá (Prochilodus lineatus). Fingerlings of lambari (0.8 ± 0.8 g) were stocked in twelve earthen-ponds (0.015 ha) at the density of 50 fish m−2. Eight ponds were stocked with juveniles of Amazon river prawn (1.1 ± 0.2 g) at the density of 25 prawn m−2. Four of these eight ponds were stocked with curimbatá fingerlings (0.2 ± 0.1 g) at a density of 13 fish m−2. Only lambari was fed twice a day with an extruded commercia...

Research paper thumbnail of A bioeconomic analysis of the potential of seaweed Hypnea pseudomusciformis farming to different targeted markets

Aquaculture Economics & Management

Research paper thumbnail of The effect of choice of targeted market, production scale, and land tenure on the economics of integrated tilapia-prawn production

Aquaculture Economics & Management

Integrated aquaculture systems have the potential to enhance the environmental sustainability of ... more Integrated aquaculture systems have the potential to enhance the environmental sustainability of aquaculture production, if economically feasible. Data from integrated tilapia-prawn production trials were used to develop economic-engineering enterprise budgets for ponds with and without substrate that targeted two different types of markets, using two production scales and two forms of land tenure. Inclusion of substrate increased investment and fixed costs and decreased net returns. Recreational markets (live tilapia for fee fishing and live prawns as bait) were profitable, but sales to supermarkets were not. Production scale and land tenure affected economic outcomes with increased pond size and leasing ponds demonstrating greater profitability. Results provide evidence of the need to carefully evaluate economic trade-offs associated with varying commercial-scale applications to increase the likelihood of adoption of new technologies.

Research paper thumbnail of Chemical Profile of the Sulphated Saponins from the Starfish Luidia senegalensis Collected as by-Catch Fauna in Brazilian Coast

Natural products and bioprospecting, Jan 22, 2018

The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are disca... more The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are discarded because they do not have commercial value. In order to try to add some value to these materials, we analyzed the chemical composition of the starfish Luidia senegalensis collected in the Brazilian coast as a consequence of the trawling fishery method. In order to access their chemical composition, we used a combination of solid phase extraction (SPE) followed by ultra-high performance liquid chromatography coupled to electrospray ionization ion trap tandem mass spectrometry (UPLC-ESI-IT-MS). Luidia senegalensis contains asterosaponins, which are sulphated glycosilated steroids, containing five and six sugar moieties, in addition to polyhydroxysteroids. This study helped us to support the presence of important and potentially bioactive compounds in invertebrates associated to the by-catch fauna of the shrimp fishery, using a fast and efficient method.

Research paper thumbnail of Concentrações de amônia, nitrito e nitrato em larvicultura do camarão <em>Macrobrachium rosenbergii</em> (De Man), realizada em sistema fechado com água salobra natural e artificial

Acta Scientiarum. Animal Sciences

RESUMO. Avaliou-se o efeito da água salobra natural e artificial e da sua utilização em dois cult... more RESUMO. Avaliou-se o efeito da água salobra natural e artificial e da sua utilização em dois cultivos consecutivos sobre as concentrações de amônia, nitrito e nitrato, em sistema fechado de larvicultura de M. rosenbergii (Crustacea, Decapoda). A amônia oscilou entre 1,1 e 74,0 µg/l e o nitrito entre e 1,1 e 34,6 µg/l; estes não diferiram entre os tipos de água analisados. A concentração de nitrato (N) aumentou ao longo do tempo (T) de forma similar na água natural e artificial, seguindo um modelo linear (N = 0,241T-0,734). Os resultados indicaram que a água salobra artificial não alterou o processo de nitrificação, tampouco o comportamento das principais variáveis ambientais. A reutilização da água também não produziu nenhum efeito negativo sobre essas variáveis. A fórmula de água do mar artificial aqui apresentada pode ser, portanto usada em sistemas de recirculação para a produção de pós-larvas de M. rosenbergii em até dois cultivos consecutivos.

Research paper thumbnail of Successful invasion of the Amazon Coast by the giant river prawn, Macrobrachium rosenbergii: evidence of a reproductively viable population

Research paper thumbnail of Economics and Management of Freshwater Prawn Culture in Western Hemisphere

Shrimp Culture, 2006

... A comprehensive sum-mary of M. rosenbergii economics around the world through the year 2000 i... more ... A comprehensive sum-mary of M. rosenbergii economics around the world through the year 2000 is provided by Rhodes (2000). ... Grow-out phase in temperate regions is presented in Tidwell and D&#x27;Abramo (2000), while grow-out phase in subtropical and tropical regions is ...

Research paper thumbnail of Intensification of the Giant river prawn Macrobrachium rosenbergii hatchery production

Aquaculture Research, 2015

Research paper thumbnail of Effect of tank colour on larval performance of the Amazon River prawn Macrobrachium amazonicum

Aquaculture Research, 2012

The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcust... more The aim of this study was to evaluate the effect of the replacement of Artemia nauplii by eggcustard in the final phase of Macrabrachium amazonicum hatchery. The treatments were: AN-IXlarvae were fed Artemia nauplii during all culture and when they reached stage V, inert diet was added to the feed (control); AN-VIIlarvae were fed Artemia nauplii from stage II to stage VI and it was totally replaced by inert diet from stage VII onwards; AN-Vlarvae were fed Artemia nauplii from stage II to stage IV and it was totally replaced by inert diet from stage V onwards. Larvae were reared in 120-L culture tanks, coupled to biological filters. Larvae largely ingested inert diet when it was the single food available (90-100% of animals showed digestive tract full). Nonetheless, feeding larvae of M.

Research paper thumbnail of Toward a good scientific writing

International Aquatic Research, 2014

Some editors point to the ''lack of style'' as a major deficiency of the manuscripts submitted fo... more Some editors point to the ''lack of style'' as a major deficiency of the manuscripts submitted for publication. Producing an adequate text is an arduous and time-consuming task, even for those who have mastered the scientific language. We should revise what we wrote many times to achieve an acceptable product. Scientific language should be clear, objective, written in proper sequence, with short sentences and long paragraphs. The following points are some practical guidelines to start writing in a good scientific style.

Research paper thumbnail of Measuring sustainability in aquaculture systems

Research paper thumbnail of Freshwater prawns

Research paper thumbnail of Impact of maintenance of Macrobrachium rosenbergii De Man, 1879 (Crustacea, Decapoda, Palaemonidae) broodstock on the water used in culture ponds

Brazilian Journal of Biology, 2011

Aquaculture production generates social and economic benefits, but can also cause environmental i... more Aquaculture production generates social and economic benefits, but can also cause environmental impacts. The objectives of this study were: a) to characterise the impacts caused by the maintenance of broodstock of the giant river prawn (Macrobrachium rosenbergii) on the physical and chemical characteristics of the water used in culture ponds, and b) to evaluate the relationship between the biomass of the prawns and the impact of culture on the water used in the ponds. Between January and December 2004, we determined, monthly, the biomass of M. rosenbergii by means of biometrics, and the physical and chemical variables of the supply and effluent water from a pond used to maintain breeding stock. The results showed that the effluent water had higher contents of chlorophyll-a, suspended particulate matter (SPM), pH, dissolved oxygen, total Kjeldahl nitrogen (TKN) and dissolved Kjeldahl nitrogen (DKN), inorganic nitrogen (IN), total (TP) and dissolved phosphorus (DP), and P-orthophospha...