Common moist diet replacement to promote sustainable Cobia Rachycentron canadum (Linnaeus) near - shore farming in Brazil

Cobia is one of the most promising warm water aquaculture species. In Brazil, cobia farming began in 2008 in the state of Rio de Janeiro from experimental scale facilities to regular near-shore farms based on fresh/frozen fish diets composed mostly of Sardinella sp. Despite the encouraging results achieved in the promotion of sustainable cobia farming, we advocate the replacement of fresh/frozen fish by a practical formulated feed. This experiment evaluated the zootechnical performance and environmental efficiency of moist and practical formulated feeds in early grow-out phases in the cycle of cobia nearshore cage culture. Four hundred and twenty juvenile cobia (151 ± 7 g) were fed with moist feed and practical formulated feed for 56 days. Biometrics were taken every two weeks and diets were analyzed for proximate composition, fatty acid composition and pellet quality. Although growth performance was equivalent between treatments, feed consumption and feed conversion ratios (FCR) were different (p < 0.05) and varied according to water temperature. Cobia fed moist feed exhibited an FCR two times higher than those fed formulated feed. Elevated settling speed and low floatability contributed to higher heterogeneity and lower efficiency of fish fed moist diet. Nitrogen excretion rate was reduced (64 %) and protein efficiency ratio elevated (27 %) within formulated diet groups in comparison to those fed moist diet (79 % and 15 %, respectively). The fatty acid profile of cobia muscle was similar across the groups. With no negative effects of diet substitution on production performance and improvement of environmental efficiency, this approach can be applied and advocated globally and contribute to the responsible intensification of sustainable marine fish culture.(AU)

Common moist diet replacement to promote sustainable Cobia Rachycentron canadum (Linnaeus) near - shore farming in Brazil

Cobia is one of the most promising warm water aquaculture species. In Brazil, cobia farming began in 2008 in the state of Rio de Janeiro from experimental scale facilities to regular near-shore farms based on fresh/frozen fish diets composed mostly of Sardinella sp. Despite the encouraging results achieved in the promotion of sustainable cobia farming, we advocate the replacement of fresh/frozen fish by a practical formulated feed. This experiment evaluated the zootechnical performance and environmental efficiency of moist and practical formulated feeds in early grow-out phases in the cycle of cobia nearshore cage culture. Four hundred and twenty juvenile cobia (151 ± 7 g) were fed with moist feed and practical formulated feed for 56 days. Biometrics were taken every two weeks and diets were analyzed for proximate composition, fatty acid composition and pellet quality. Although growth performance was equivalent between treatments, feed consumption and feed conversion ratios (FCR) were different (p < 0.05) and varied according to water temperature. Cobia fed moist feed exhibited an FCR two times higher than those fed formulated feed. Elevated settling speed and low floatability contributed to higher heterogeneity and lower efficiency of fish fed moist diet. Nitrogen excretion rate was reduced (64 %) and protein efficiency ratio elevated (27 %) within formulated diet groups in comparison to those fed moist diet (79 % and 15 %, respectively). The fatty acid profile of cobia muscle was similar across the groups. With no negative effects of diet substitution on production performance and improvement of environmental efficiency, this approach can be applied and advocated globally and contribute to the responsible intensification of sustainable marine fish culture.

Analysis of the marine shrimp farm production chain in Rio Grande do Sul state / Análise da cadeia produtiva da cultura de camarão marinho no sul do Brasil

This study aims to identify, describe, and analyze the main links of the marine shrimp culture production chain in the extreme south of Brazil, specifically in the Rio Grande and São José do Norte municipalities, Rio Grande do Sul state. The research was carried out through prior bibliographic, in loco research and the application of interviews and questionnaires to identify the entire local productive process from the inputs needed for production to the arrival at the final consumer. The results indicate that the production chain requires actions in the process until the products final commercialization. Even as a growing market in Brazil, more investments, better support from the Government for the installation of new farmers, a reduction of bureaucracy in public agencies, training of actors involved in production, and some other points identified in this study can help decision makers, inherent to the activity, to establish sustainable production strategies aimed at lasting and full development of local shrimp production.(AU)

Este estudo tem como objetivo identificar, descrever e analisar os principais elos da cadeia produtiva do camarão marinho no extremo sul do Brasil, especificamente nas cidades de Rio Grande e São José do Norte, estado do Rio Grande do Sul. A pesquisa foi realizada por meio de uma revisão bibliográfica prévia, pesquisa in loco e aplicação de entrevistas e questionários para identificar todo o processo produtivo local a partir dos insumos necessários para a produção até a chegada ao consumidor final. Os resultados indicam que a cadeia produtiva requer ações desde o processo até a comercialização final do produto. Mesmo com um mercado em crescimento no Brasil, mais investimentos, mais apoiodo Governo para a instalação de novos agricultores, a redução da burocracia em órgãos públicos, o treinamento de atores envolvidos na produção, e alguns outros pontos identificados neste estudo podem ajudar os tomadores de decisão, inerente à atividade, a estabelecerem estratégias de produção sustentáveis que visam um desenvolvimento da produção local de camarão duradouro e completo.(AU)

Analysis of the marine shrimp farm production chain in Rio Grande do Sul state / Análise da cadeia produtiva da cultura de camarão marinho no sul do Brasil

This study aims to identify, describe, and analyze the main links of the marine shrimp culture production chain in the extreme south of Brazil, specifically in the Rio Grande and São José do Norte municipalities, Rio Grande do Sul state. The research was carried out through prior bibliographic, in loco research and the application of interviews and questionnaires to identify the entire local productive process from the inputs needed for production to the arrival at the final consumer. The results indicate that the production chain requires actions in the process until the product’s final commercialization. Even as a growing market in Brazil, more investments, better support from the Government for the installation of new farmers, a reduction of bureaucracy in public agencies, training of actors involved in production, and some other points identified in this study can help decision makers, inherent to the activity, to establish sustainable production strategies aimed at lasting and full development of local shrimp production.

Este estudo tem como objetivo identificar, descrever e analisar os principais elos da cadeia produtiva do camarão marinho no extremo sul do Brasil, especificamente nas cidades de Rio Grande e São José do Norte, estado do Rio Grande do Sul. A pesquisa foi realizada por meio de uma revisão bibliográfica prévia, pesquisa in loco e aplicação de entrevistas e questionários para identificar todo o processo produtivo local a partir dos insumos necessários para a produção até a chegada ao consumidor final. Os resultados indicam que a cadeia produtiva requer ações desde o processo até a comercialização final do produto. Mesmo com um mercado em crescimento no Brasil, mais investimentos, mais apoiodo Governo para a instalação de novos agricultores, a redução da burocracia em órgãos públicos, o treinamento de atores envolvidos na produção, e alguns outros pontos identificados neste estudo podem ajudar os tomadores de decisão, inerente à atividade, a estabelecerem estratégias de produção sustentáveis que visam um desenvolvimento da produção local de camarão duradouro e completo.

Compostos nitrogenados sobre o consumo alimentar de camarão-rosa Farfantepenaeus brasiliensis / Nitrogen compounds on food consumption of pink-shrimp Farfantepenaeus brasiliensis

Os experimentos foram realizados para investigar os efeitos da amônia, nitrito e nitrato no consumo alimentar de juvenis de Farfantepenaeus brasiliensis. Os camarões com peso médio de 4g foram aclimatados durante 28 dias em diferentes concentrações crônicas de amônia, nitrito e nitrato. Após o período de exposição de 28 dias, 20 camarões por tratamento foram individualizados em unidades experimentais de 3 L, a fim de ser analisado o consumo de ração em função da quantidade de alimento oferecido e as sobras durante um período de 24 horas. O consumo alimentar apresentou alterações significativas (P<0,05) para os camarões expostos às concentrações de nitrito e nitrato testadas, enquanto para o tratamento com amônia, os camarões não apresentaram alterações no consumo alimentar (P>0,05). Foi verificado que o nitrito e o nitrato afetam o consumo alimentar de F. brasiliensis. Contudo, a possibilidade de que isso ocorra durante longos períodos, afetando negativamente o cultivo de espécies em cativeiro, reforçam a necessidade do manejo da qualidade de água.

The experiments were carried out to investigate the effects of ammonia, nitrite and nitrate on food consumption of juvenile F. brasiliensis. The juvenile shrimp were acclimated for 28 days with different cronic concentrations of ammonia, nitrite and nitrate. After the acclimation period, 20 shrimps per treatment were individualized in 3 L experimental units in order to analyze their feed intake through the amount of feed offered and leftover for a period of 24 hours. The food consumption presented significant alteration (P<0.05) for the nitrite and nitrate concentrations tested, meanwhile on ammonia treatment, shrimp presented no alteration on food intake (P>0.05). According to the results obtained, nitrite and nitrate affected F. brasiliensis food consumption. However, the possibility of this to happen over long periods, can damage the species in captivity, reinforced the necessity of regular water quality management.

Shrimp farming as an alternative to artisanal fishermen communities: the Case of Patos Lagoon, Brazil

The shrimp Farfantepenaeus paulensis is considered a suitable species for culture in the Patos Lagoon estuary, southern Brazil, where its catch has been decreasing in the last few years. Considering the potential of estuarine areas for shrimp farming, the application of low-cost structures to culture shrimp, such as the pen enclosures, is being proposed as an alternative source of income for artisanal fishermen and farmers living near Patos Lagoon. From an economical standpoint, these alternative systems present several advantages over the traditional pond-based culture systems since land, water pumping and artificial aerations are not required, high natural productivity is available and inexpensive materials are employed in the construction of grow-out structures. This paper reviews the farming of F. paulensis in the pen enclosures as an alternative to the artisanal fishing communities of the Patos Lagoon estuary. Particular emphases are placed on the development of culture systems, social and environmental impacts, constraints and perspectives.

O camarão-rosa Farfantepenaeus paulensis é considerado uma espécie com potencial para criação no estuário da Lagoa dos Patos, RS, onde o volume desembarcado deste recurso vem decrescendo nos últimos anos. A criação deste camarão em cercados está sendo proposta como uma fonte de renda alternativa para os pescadores artesanais e agricultores que habitam o entorno deste estuário. Do ponto de vista econômico, estes sistemas alternativos de criação apresentam vantagens sobre os sistemas tradicionais em viveiros de terra: não se necessita ter posse da terra, nem equipamentos de bombeamento d'água ou aeração. Além disso, materiais relativamente baratos são utilizados na construção das estruturas de engorda e há uma grande disponibilidade de alimento natural. Esta revisão apresenta alguns aspectos da criação de F. paulensis em cercados como uma alternativa às comunidades de pescadores. Maior ênfase será dada no desenvolvimento dos sistemas de criação, manejo, impactos sociais e ambientais, dificuldades e possibilidades.