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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Densidade de estocagem em camar?es da esp?cie Macrobrachium rosenbergii (De Man, 1879) na fase juvenil

Costa, Jamilly de Souza 30 April 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-12-03T23:08:55Z No. of bitstreams: 1 JamillyDeSouzaCosta_DISSERT.pdf: 1873377 bytes, checksum: 1b4c6d02d280989d1909ffd15251b0ba (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2015-12-09T22:15:12Z (GMT) No. of bitstreams: 1 JamillyDeSouzaCosta_DISSERT.pdf: 1873377 bytes, checksum: 1b4c6d02d280989d1909ffd15251b0ba (MD5) / Made available in DSpace on 2015-12-09T22:15:12Z (GMT). No. of bitstreams: 1 JamillyDeSouzaCosta_DISSERT.pdf: 1873377 bytes, checksum: 1b4c6d02d280989d1909ffd15251b0ba (MD5) Previous issue date: 2014-04-30 / Entre as diversas atividades aqu?colas, a carcinicultura sobressai-se devido ao alto valor comercial que os crust?ceos atingiram no mercado. Dentre as esp?cies de ?gua doce cultivadas, uma das que mais t?m se destacado ? Macrobrachium rosenbergii. O conhecimento sobre o comportamento da esp?cie e a influ?ncia das caracter?sticas do ambiente em seu desenvolvimento pode otimizar o manejo e minimizar prov?veis impactos ao meio ambiente e ao pr?prio animal. Assim, nosso objetivo geral foi caracterizar as atividades comportamentais dessa esp?cie nos est?gios iniciais do desenvolvimento em diferentes densidades de estocagem, nas fases do ciclo de luz. P?s-larvas com 30 dias de vida foram trazidas da Escola Agr?cola de Jundia? (EAJ), Maca?ba/RN e, em seguida, transferidas para o laborat?rio de Estudos do Comportamento do Camar?o (LECC), da Universidade Federal do Rio Grande do Norte (UFRN), onde foram medidas e pesadas. Para cada experimento, foram utilizados oito aqu?rios de 60 L (40 cm x 30 cm x 50 cm), com temperatura e aera??o constantes e filtra??o cont?nua atrav?s de m?dias filtrantes biol?gicas em mini-tubos, areia, l? de vidro e carv?o vegetal, contendo tr?s cent?metros de areia de filtro de piscina (granulometria m?dia) como substrato e submetidos ao ciclo de 12h/12h, tendo 30% da ?gua trocada uma vez por semana. Os abrigos utilizados foram peda?os de tijolos, sendo 2 em cada aqu?rio. A qualidade da ?gua foi monitorada semanalmente. Para observa??o do comportamento dos animais, utilizamos duas densidades: 25 animais m-? e 40 animais m-?. Os comportamentos foram observados atrav?s dos seguintes m?todos de registro: amostragem comportamental - entrada e sa?da do abrigo, coleta de alimento no substrato e na coluna d??gua, afastamento, ataque, persegui??o e canibalismo; scan - inatividade, alimenta??o, explora??o, cava??o, nata??o, limpeza e perman?ncia no abrigo. As observa??es ocorreram em janelas de 15 minutos/aqu?rio, 4 vezes ao dia, por 4 dias na semana, ao longo de 4 semanas. O alimento foi ofertado 2 vezes ao dia, imediatamente antes de 2? e da 4? janela de observa??o de cada aqu?rio. Nossos resultados demonstraram que na alta densidade, na fase de claro, os animais apresentaram maior frequ?ncia de atividades comportamentais que possivelmente promoveram menor exposi??o, e tamb?m evita??o de atos agon?sticos. Nessa densidade, na fase de escuro, a maior frequ?ncia foi de comportamentos que pareceram gerar maior exposi??o a riscos. Para a baixa densidade, encontramos um padr?o que pode ser importante para o manejo ao gerar mais conforto aos animais no ambiente de cultivo. Concluiu-se que a densidade de estocagem exerceu influ?ncia na express?o das atividades comportamentais de M. rosenbergii nos est?gios iniciais do desenvolvimento, com modifica??es no comportamento que indicam bem-estar pobre ao animal em condi??es de alta densidade de estocagem. / Among the species of freshwater shrimp being cultivated, Macrobrachium rosenbergii stands out. Knowledge about the behavior of this species and the influence of certain factors on its development can help optimize management practices and minimize the likely impacts shrimp farming has on the environment and the animals themselves. The objective of this study was to characterize the species' behavior during early stages of development under different stocking densities over a 24-hour cycle. Ten day old postlarvae were transferred from the Jundia? School of Agriculture (EAJ - Escola Agr?cola de Jundia?) in Maca?ba (RN), Brazil to the Shrimp Behavior Laboratory (LSPR - Laborat?rio de Estudos do Comportamento do Camar?o) at the Federal University of Rio Grande do Norte (UFRN), where they were weighed and measured. Eight aquaria with constant temperature, aeration and filtration, and subjected to a12 h light/12 h dark cycle were used for each experiment. Each aquarium also contained two shelters made of bricks and the water quality was monitored weekly. Behavioral observations were made at two densities: 25 individuals/m-? and 40 individuals/m-?. The methods for recording behaviors were: behavioral sampling ? enter and leave the shelter, exploring on the substrate, exploring in the water column, move away, attack, pursuit and cannibalism; scan sampling - inactivity, feeding, exploration, digging, swimming, cleaning and staying in the shelter. Observations were made during a 15 minute period/per aquarium at a frequency of 4 times daily, for 4 days/week, and over 4 weeks. Food was provided 2 times/day for each aquarium population, immediately before the 1st and 3rd observation periods. Our results demonstrate that at high density, there is an increased frequency of agonistic behavior; during the light phase, there is a greater frequency of behaviors that result in less exposure (inactivity, cleaning and staying in the shelter); during the dark phase, there is an increased frequency of behaviors that result in greater exposure (feeding, exploration, swimming and digging); at times of feed offer, there is an increased frequency of leaving the shelter, moving away, pursuit, feeding, exploration and swimming. At low density, the animals showed a lower frequency of agonistic behaviors, greater weight gain and higher growth rates, which indicates that this is a more favorable growing environment for cultivation and when applied, can generate better living conditions, favor survival rates and increase management success
22

Desempenho zoot?cnico dos camar?es: Litopenaeus vannamei e Macrobrachium rosenbergii em tanques rede e aquicultura familiar na comunidade de Bebida-Velha, RN / Performance of shrimps Litopenaeus vannamei livestock Macrobrachium rosenbergii in cages and aquaculture family in Bebida Velha community, RN

Medeiros, Priscila Maria Oliveira Campos 10 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-10T00:14:52Z No. of bitstreams: 1 PriscilaMariaOliveiraCamposMedeiros_DISSERT.pdf: 1682569 bytes, checksum: 4c9914ef6bdc76ec09d3b21d2a0a8622 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-16T21:20:13Z (GMT) No. of bitstreams: 1 PriscilaMariaOliveiraCamposMedeiros_DISSERT.pdf: 1682569 bytes, checksum: 4c9914ef6bdc76ec09d3b21d2a0a8622 (MD5) / Made available in DSpace on 2016-03-16T21:20:13Z (GMT). No. of bitstreams: 1 PriscilaMariaOliveiraCamposMedeiros_DISSERT.pdf: 1682569 bytes, checksum: 4c9914ef6bdc76ec09d3b21d2a0a8622 (MD5) Previous issue date: 2015-02-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / O estudo visa avaliar o desempenho zoot?cnico e identificar as les?es das intera??es agon?sticas do camar?o Macrobrachium rosenbergii em diferentes densidades em tanques rede (cap?tulo 1); comparar o desempenho zoot?cnico dos M. rosenbergii e Litopenaeus vannamei em tanques rede (cap?tulo 2); al?m de conhecer os saberes e fazeres de uma comunidade tradicional de aquicultores de Bebida-Velha, no munic?pio de Pureza/RN, que praticam a aquicultura rural e familiar, bem como tra?ar o perfil socioecon?mico da comunidade e avaliar o manejo que estes aquicultores utilizam no cultivo de camar?es M. rosenbergii (cap?tulo 3). Para realizar os experimentos (cap?tulo 1 e 2) os camar?es das esp?cies L. vannamei e M. rosenbergii foram pesados em balan?a digital e transferidos a cultivos em tanques rede. Os tanques rede possu?am 1m?, com malha de 5 mm entre n?s e foram fechados em cima com tela para evitar a a??o de predadores (aves, insetos). Os animais permaneceram em adapta??o por quinze dias antes do in?cio da coleta de dados (de cada experimento). Os dois experimentos duraram setenta dias, totalizando oitenta e cinco dias de cultivo. Durante os cultivos, os animais foram alimentados com ra??o peletizada para camar?o em 10% da sua biomassa, com 35% de prote?na bruta, ofertada em bandejas de alimenta??o duas vezes por dia nos hor?rios (7:00 h e 14:00 h). A sobra na bandeja foi retirada ap?s 2h de perman?ncia para calcularmos o consumo. Para determinar os par?metros zoot?cnicos, biometrias foram realizadas a cada 10 dias. Os resultados dos dois experimentos foram analisados atrav?s do programa STATISTIC 7.0 (2004). No experimento do cap?tulo 1 foram aplicados 5 tratamentos, com 5 repeti??es cada: D5 - 5 animais/m2 ; D10 - 10 animais/m2 ; D15 - 15 animais/m2 ; D20 - 20 animais/m2 e D25 - 25 animais/m2 . Para isso, 25 tanques rede foram distribu?dos aleatoriamente em 2 viveiros de alvenaria. No final do experimento as les?es foram verificadas e quantificadas. O experimento do cap?tulo 2 teve in?cio quando os camar?es alcan?aram a mesma idade (oitenta e quatro dias) e foi utilizado a densidade de 25 camar?es/m2 com 4 repeti??es. Para a realiza??o do cap?tulo 3, foram aplicadas entrevistas semi-estruturadas atrav?s de abordagem direta dos assentados de Bebida Velha praticantes da atividade de aquicultura, produtores de til?pia e camar?o da comunidade. Os dados coletados foram tabulados e analisados de acordo com as respostas obtidas pelos participantes. Portanto, foi constatado que a quantidade de les?es aumentou com o aumento 7 da densidade de estocagem e que a densidade de 10 camar?es de ?gua doce/m? apresentou as melhores condi??es para obter um melhor desempenho em tanques rede. O cultivo em tanques rede da esp?cie de camar?o de ?gua doce M. rosenbergii teve melhores ?ndices zoot?cnicos do que o cultivo da esp?cie de camar?o marinho L. vannamei. Foi poss?vel verificar que as atividades das quais os entrevistados praticam, garantem uma boa qualidade de vida e renda para eles, al?m disso, os entrevistados possuem conhecimento tradicional do saber e fazer, e tamb?m se mostram interessados no cultivo da esp?cie M. rosenbergii. / The study aims to evaluate the performance and identify lesions of agonistic interactions of Macrobrachium rosenbergii in different densities cages (chapter 1); compare the growth performance of shrimp M. rosenbergii and Litopenaus vannamei cages (chatper 2); in addition the study aimed at identifying the knowledge and practices of a traditional community of farmers Bebida-Velha, in the city of Pureza / RN, practicing rural family and aquaculture, as well as tracing the community socioeconomic profile and evaluate the management that these farmers use in shrimp farming Macrobrachium rosenbergii (chapter 3). To perform the experiments (chapter 1 and 2) shrimp species L. vannamei and M. rosenbergii were weighed on a digital scale and transferred to cultures in cages. The cages had 1m?, with 5mm mesh between us and were closed on top with screen to avoid predators (birds, insects). The animals remained in adaptation for fifteen days before the start of data collection (each experiment). Both experiments lasted seventy days, totaling eighty-five days cultivation. During the cultures, animals were fed pelleted feed for shrimp at 10% of their biomass with 35% crude protein, offered in feed trays twice a day during the hours (7:00 am and 14:00 pm). The remnants in the tray were removed after 2h of permanence to calculate intake. To determine the performance parameters, some samples were taken every 10 days. The results of both experiments were analyzed using the STATISTIC 7.0 (2004). In Chapter 1 experiment were applied5 treatments were applied with 5 replications each: D5 - 5 animals/m2 ; D10 - 10 animals/m2 ; D15 - 15 animals/m2 ; D20 - 20 animals/m2 ; D25 - 25 animals/m2 . To this, were distributed 25 cages randomly in two masonry nurseries. The end of the experiment the lesions were verified and quantified. The chapter 2 experiment began when the shrimp reached the same age (eighty-four days) and was used the density of 25 shrimp / m2 with 4 repetitions. For the realization of chapter 3 were applied semi-structured interviews by direct approach of Bebida Velha of settlers practicing aquaculture activity, tilapia producers and community shrimp. Data were tabulated and analyzed according to the responses obtained by the participants. Therefore, the amount of damage increased with increasing stocking density. The density of 10 freshwater shrimp/m? showed the best conditions for a better performance in cages. It can be concluded that in cages, the cultivation of species of fresh water shrimp M. rosenbergii had better zootechnical indexes than the cultivation of marine shrimp species L. 9 vannamei. It was possible to verify that the activities of which the interviewees practice guarantee a good quality of life and income for them. We find that respondents have traditional and local knowledge, and also may be interested in the cultivation of the species M. rosenbergii.
23

Produção, análise econômica e sustentabilidade da rizicarcinicultura no Estado de São Paulo

Boock, Marcello Villar [UNESP] 17 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-17Bitstream added on 2014-06-13T19:19:21Z : No. of bitstreams: 1 boock_mv_dr_jabo.pdf: 816842 bytes, checksum: 01fc8022e8314991c83533aef2b391ec (MD5) / Universidade Estadual Paulista (UNESP) / Os sistemas de aquicultura integrada otimizam o uso dos recursos naturais, das instalações e da mão-de-obra, ampliando a sustentabilidade ambiental e econômica. Permitem ainda, a transformação de poluentes em biomassa de alto valor econômico. No presente estudo foram estudadas duas espécies de camarões de água doce, o camarão-da-malásia (M. rosenbergii) e o camarão-daamazônia (M. amazonicum), criados em sistema integrado simultâneo com a cultura do arroz irrigado por inundação na região nordeste do Estado de São Paulo. As variáveis de produção: comprimento, peso, produção e produtividade foram estudadas para ambas as espécies de camarão. Para o sistema de monocultivo do arroz avaliou-se a produção e a produtividade do arroz, comparando-se estas às obtidas para o sistema de rizicarcinicultura. Indicadores de viabilidade econômica foram calculados para os sistemas de monocultivo de arroz e de rizicarcinicultura. Os indicadores de sustentabilidade ambiental foram calculados para comparar a sustentabilidade dos sistemas de monocultivo de arroz e da rizicarcinicultura (com M. amazonicum). Medições da emissão de gás metano (CH3 -), gás carbônico (CO2 -), estimativas da excreção de amônia (NH3 +) e do conteúdo de nitrogênio e fósforo nas fezes dos camarões também foram realizadas / Aquaculture integrated systems optimize the use of natural resources, facilities and manpower, expanding economical and environmental sustainability. They also allow to transform pollutants into biomass of high economic value. The present study focus on two species of freshwater prawns, Macrobrachium rosenbergii and Macrobrachium amazonicum, reared in a simultaneous integrated system with rice (Oryza sativa) culture irrigated by flooding, in the northeastern region of Sao Paulo State. Production variables were determined for both prawn species: length, weight, production and productivity. Production and productivity were also determined for the rice monoculture in order to compare with the production variables of the rice-prawn system. Financial feasibility indicators were determined for the rice monoculture and for the rice-prawn system. Environmental Sustainability indicators were calculated to compare the sustainability of rice monoculture system and rice-prawn (M. amazonicum) system. The emissions of methane gas (CH3 -) and carbonic gas (CO2 -) were measured; ammonium (NH3 +) excretion, nitrogen and phosphorus contents in feces of the prawns were estimated too
24

Tecnologia pós-despesca dos camarões de água doce Macrobrachium rosenbergii e Macrobrachium amazonicum

Portella, Carolina De Gasperi [UNESP] 03 July 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-03Bitstream added on 2014-06-13T20:00:51Z : No. of bitstreams: 1 portella_cg_dr_jabo.pdf: 619272 bytes, checksum: 967fa2a2ecd78204650d28b2592f3a8e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Macrobrachium amazonicum e Macrobrachium rosenbergii são espécies de camarão de água doce de grande importância econômica e como fontes de alimento de alto valor nutritivo. Existem poucas informações a respeito da composição química do camarão de água doce produzido no Brasil. O objetivo deste trabalho foi avaliar a composição química das duas espécies e determinar o perfil de aminoácidos de M. amazonicum. Exemplares provenientes de cultivo foram lavados e limpos (retirada cefalotórax e exoesqueleto) para a determinação dos teores de umidade, proteína, cinzas, lipídeos e aminoácidos totais. Os teores de umidade foram 76,55 e 78,39g/100g, cinzas de 1,34 e 1,31g/100g, proteína de 21,49 e 18,48g/100g e lipídeo de 1,48 e 1,17g/100g, para M. amazonicum e M. rosenbergii, respectivamente. O conteúdo total de M. amazonicum foi 20,60g/100g. Os aminoácidos mais representativos foram ácidos glutâmico e aspártico, arginina, alanina e glicina. Estes dados podem ser utilizados futuramente como informação nutricional aos consumidores e para análises em estudos de nutrição e no processamento. / Species of freshwater prawn Macrobrachium amazonicum and Macrobrachium rosenbergii are species of freshwater prawn of great importance and that may be utilized as source of high nutritional value food. There are few data about the chemical composition of freshwater prawns produced in Brazil. The aim of this study was evaluate the chemical composition of both species and determinate the amino acids profile of M. amazonicum and M. rosenbergii. Samples from culture were washed and have peeled tails. They were determined moisture, protein, ash, lipid and total amino acids contents. The values of moisture were 76.55 and 78.39g/100g, ash 1.34 and 1.31g/100g, protein 21.49 and 18.48g/100g and lipid 1.48 and 1.17g/100g to M. amazonicum and M. rosenbergii, respectively. The total amino acid content of M. amazonicum were 20.60g/100g. The most abundant amino acids were glutamic and aspartic acids, arginine, alanine, and glycine. These data may use as nutritional information for consumers and for future analysis on nutrition and processing.
25

Produção, análise econômica e sustentabilidade da rizicarcinicultura no Estado de São Paulo /

Boock, Marcello Villar. January 2012 (has links)
Orientador: Wagner Cotroni Valenti / Coorientador: Patrícia Maria Contente Moraes Valenti / Banca: Margarete Mallasen / Banca: Iracy Lea Pecora / Banca: Hélio Minoru Takada / Banca: Helcio Luis de Almeida Marques / Resumo: Os sistemas de aquicultura integrada otimizam o uso dos recursos naturais, das instalações e da mão-de-obra, ampliando a sustentabilidade ambiental e econômica. Permitem ainda, a transformação de poluentes em biomassa de alto valor econômico. No presente estudo foram estudadas duas espécies de camarões de água doce, o camarão-da-malásia (M. rosenbergii) e o camarão-daamazônia (M. amazonicum), criados em sistema integrado simultâneo com a cultura do arroz irrigado por inundação na região nordeste do Estado de São Paulo. As variáveis de produção: comprimento, peso, produção e produtividade foram estudadas para ambas as espécies de camarão. Para o sistema de monocultivo do arroz avaliou-se a produção e a produtividade do arroz, comparando-se estas às obtidas para o sistema de rizicarcinicultura. Indicadores de viabilidade econômica foram calculados para os sistemas de monocultivo de arroz e de rizicarcinicultura. Os indicadores de sustentabilidade ambiental foram calculados para comparar a sustentabilidade dos sistemas de monocultivo de arroz e da rizicarcinicultura (com M. amazonicum). Medições da emissão de gás metano (CH3 -), gás carbônico (CO2 -), estimativas da excreção de amônia (NH3 +) e do conteúdo de nitrogênio e fósforo nas fezes dos camarões também foram realizadas / Abstract: Aquaculture integrated systems optimize the use of natural resources, facilities and manpower, expanding economical and environmental sustainability. They also allow to transform pollutants into biomass of high economic value. The present study focus on two species of freshwater prawns, Macrobrachium rosenbergii and Macrobrachium amazonicum, reared in a simultaneous integrated system with rice (Oryza sativa) culture irrigated by flooding, in the northeastern region of Sao Paulo State. Production variables were determined for both prawn species: length, weight, production and productivity. Production and productivity were also determined for the rice monoculture in order to compare with the production variables of the rice-prawn system. Financial feasibility indicators were determined for the rice monoculture and for the rice-prawn system. Environmental Sustainability indicators were calculated to compare the sustainability of rice monoculture system and rice-prawn (M. amazonicum) system. The emissions of methane gas (CH3 -) and carbonic gas (CO2 -) were measured; ammonium (NH3 +) excretion, nitrogen and phosphorus contents in feces of the prawns were estimated too / Doutor
26

Efeito da substituição do milho por raspa de mandioca em rações do camarão da Malasia "Macrobrachium rosenbergii" De Man , 1879

Correia, Eudes de Souza January 1993 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina. Centro de Ciencias Agrarias. Inclui apendice / Made available in DSpace on 2012-10-16T05:05:27Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-08T18:22:01Z : No. of bitstreams: 1 92207.pdf: 2622436 bytes, checksum: ff3291e0dea79524954228878d349032 (MD5) / Quatro dietas isonitrogenadas (25% de pb) e isocalóricas (2,9kcal/g de energia digestível) foram testadas em três experiências, quanto à estabilidade em água, ao consumo voluntário de matéria seca e ao crescimento. Camarões Macrobrachium rosenbergii na fase de engorda, visando avaliar o efeito da substituição do milho por raspa de mandioca . As rações foram compostas de vários ingredientes sendo que o milho e a mandioca representaram 51% da dieta, em proporções respectivas para as 4 dietas de 51 e 0%; 34 e 17%; 17 e 34% e 0 e 51%, correspondendo a uma substituição do milho por raspa de mandioca na ordem de 0,0; 33,3; 66,7 e 100%, respectivamente. A estabilidade foi avaliada com imersão dos peletes em água doce durante 30, 60, 120, 240 e 360 min. O consumo de matéria seca foi mensurado com camarões de cinco faixas de tamanho em áquarios de 40l. Quanto à avaliação do crescimento, 16 gaiolas cilíndricas de 1m2 foram mantidas em um viveiro de 1800 m2 e cada uma estocada com 8 camarões juvenis. Quanto ao crescimento, todas as dietas testadas não apresentam diferenças significativas (p > 0,05) com relação ao ganho de peso individual, ganho de biomassa, sobrevivência e conversão alimentar, sendo constatada a possibilidade de substituição de 100% de milho, correspondendo à utilização de até 51% de raspa de mandioca em rações de engorda desse camarão, desde que sejam atendidos os requerimentos nutricionais da espécie.
27

Efeito de densidades de estocagem e de aeração suplementar na produção intensiva do camarão de agua doce, MACROBRACHIUM ROSENBERGII, (de Man, 1879)

Andrade, Humberto Ker de January 1995 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciencias Agrarias / Made available in DSpace on 2012-10-16T09:12:10Z (GMT). No. of bitstreams: 0 / Estudou-se o efeito de duas densidades de estocagem (9,59,5 ± 0,25 e 13,5 ± 0,25 indivíduos/m²), combinadas a duas formas de aeração: estratégica e emergencial, na produção do camarão de água doce Macrobrachium rosenbergii. Num primeiro experimento foram utilizados quatro viveiros escavados com áreas variando de 1325 a 2580m², povoados com juvenis de M. rosenbergii com peso médio de 0,71 gramas cultivados durante 240 dias. No segundo experimento com duração de 180 dias, forma utilizadas 12 gaiolas experimentais com área de 2,0m² cada, distribuídas em lotes de 3 gaiolas para cada viveiro do primeiro experimento, submetendo-se os animais aos mesmos efeitos. Não houve diferenças estatísticas entre os tratamentos (P<0,05) para ganho de peso e peso individual à despesa nos viveiros e nas gaiolas. O tratamento com densidade de estocagem de 13,6 indivíduos/m² e aeração estratégica produziu a nível de viveiro o melhor resultado de biomassa final (197,5g/m²) sendo que, nos demais tratamentos, as produtividades foram semelhantes entre si (137,6; 151,0 e 143,3g/m²). Nas gaiolas, os resultados de produtividade entre os tratamentos foram de 168,8; 112,5; 117,0 e 173,5g/m², não havendo diferenças estatísticas significativas ((P<0,05) para ganho de biomassa. A sobrevivência variou nos tratamentos de 54,0 a 76,2% nos viveiros e de 88,1 a 91,6% nas gaiolas. O sistema de aeração de emergência mostrou-se mais econômico quanto ao consumo de energia elétrica, no entanto, a produtividade do tratamento com densidade de estocagem mais elevada e aeração estratégica foi maior em relação aos demais.
28

Stock improvement of giant freshwater prawn (Macrobrachium rosenbergii) in Vietnam: Experimental evaluations of crossbreeding,the impact of domestication on genetic diversity and candidate genes

Thanh Nguyen Unknown Date (has links)
Aquaculture plays an important role in economic development and food security in many countries in the world. World aquaculture production in 2006 was 51.7 million tonnes with an estimated value of US$ 78.8 billion (FAO, 2009). World production will need to increase however by 30-40 million tonnes from its current production level by 2030 to meet growing global demand for fish. In this context, aquaculture in Vietnam has developed rapidly over the past decade and the fisheries sector ranked fourth in terms of export value in 2008 (Vietnamnet, 2008). Total fisheries production in Vietnam in 2007 was 4.149 million tonnes, of which fisheries production from catch and aquaculture were 2.064 and 2.085 million tonnes, respectively. A variety of aquatic species are cultured in Vietnam, but shrimps (mainly Black Tiger shrimp Penaeus monodon, and Pacific white shrimp Litopenaeus vannamei) and ‘tra’ or ‘basa’ catfish are the most common species used in aquaculture. The giant freshwater prawn (GFP), Macrobrachium rosenbergii, is one of the most important crustacean species in inland aquaculture in many countries across the world where this species is either native or exotic. GFP is suitable for culture in a variety of farming systems, including monoculture or polyculture in ponds, pens, and integrated or rotational rice-prawn culture models. The GFP industry worldwide relies totally on wild or unimproved stocks, a practice that threatens the long-term sustainability of GFP farming due to low productivity and vulnerability of farmed stocks to disease. The current status of GFP aquaculture highlights the need for initiation of a systematic stock improvement program for the species to improve economically important traits. Large-scale selective breeding programs have been instigated for some finfish, salmonids and GIFT tilapia for example, and some selective breeding trials have been conducted on crustacean species, namely marine penaeid shrimp and freshwater crayfish. Examples of selective breeding programs on aquatic species have demonstrated that significant genetic gains can be achieved for growth rates with gains of around 10-20% per generation. While a selective breeding program is an option for GFP stock improvement, an alternative approach to improving GFP productivity, potentially with more immediate effect and one that is less expensive, is crossbreeding which may produce heterosis or hybrid vigour in crossbred offspring. Therefore, a crossbreeding strategy was trialed in the current study as a starting point for a stock improvement program for the GFP industry in Vietnam. The current study assessed the growth performance of three GFP strains (two wild Vietnamese strains from the Dong Nai and Mekong rivers, and a single domesticated Hawaiian strain) and their reciprocal crosses in a complete 3x3 diallel cross, i.e. three purebred and six crossbred strains. The diallel cross was carried out over two consecutive generations (G1 and G2). Juveniles for the experiments were produced using single-pair matings. Juveniles from each strain combination were stocked into three replicate hapas for 15 weeks. Growth data (body weight, carapace length, standard length) from the G1 and G2 were pooled for all subsequent analyses as there was no effect of generation on growth traits. Results showed that the Hawaiian strain performed best among purebred strains, and crosses with the Dong Nai or Mekong strains as dams and the Hawaiian strain as sires grew significantly faster than did the purebred Dong Nai or Mekong strains. These results suggest potential for heterosis among some crosses. Growth data were analyzed in depth by partitioning the strain combination (cross) effect into three components: strain additive genetic effects, heterotic effects, and strain reciprocal effects. Strain additive genetic and reciprocal effects were significant sources of variation for all growth traits measured. Strain additive genetic effects were highest for the Hawaiian strain and lowest for the Mekong strain for all growth traits. Reciprocal effects influenced negatively on growth rate of crosses with the Hawaiian (H) strain as dams and the Dong Nai (D) or Mekong (M) as sires compared with their reciprocal crosses (DH and MH). Heterotic effects for all growth traits were small and not significantly different from zero (P > 0.05). These results indicate that a crossbreeding approach based on the strains evaluated here provides only limited potential for improving growth rates based simply on heterotic outcomes and that a likely more productive option would be to trial artificial selection on a diverse synthetic stock. The current study also employed genetic markers (microsatellites) to characterize levels and patterns of genetic diversity in three purebred strains of GFP that originated from the diallel cross above. All three purebred strains showed relative high levels of genetic diversity in terms of allele number and individual heterozygosity across the six marker loci screened. Levels of genetic diversity present in the three purebred strains combined into a single stock were compared with that from a combination of three wild river stocks to assess the impact of domestication on genetic diversity of a ‘synthetic’ population. Results demonstrated that there was no significant loss of genetic diversity in the three purebred strains combined compared with a reference set containing the three wild populations. Therefore, a synthetic population formed from these purebred strains successfully captured the majority of genetic variation present in the wild broodstock. This synthetic population provides a potential stock for a future selective breeding program for GFP in Vietnam. The current study was also the first attempt to identify single nucleotide polymorphisms (SNPs) in key growth genes in GFP. Two key candidate genes were targeted, actin and crustacean hyperglycemic hormone (CHH), that are potentially linked to growth performance in GFP. The study screened SNPs in GFP females only, because growth performance of GFP males is influenced strongly by social rank. The study identified four SNPs in intron 3 of the CHH gene that were significantly correlated with individual body weight at harvest, while no SNPs detected in the actin gene were associated with growth traits in GFP. This finding however, needs to be confirmed using larger sample sizes and other GFP lines. The current study has produced important basic knowledge relevant to implementation of an effective stock improvement program for GFP in Vietnam. Results indicate that a selective breeding strategy rather than a crossbreeding approach is likely to be the best strategy for improving GFP culture stocks in Vietnam. In addition, the study demonstrates that application of modern molecular genetic technologies can be efficient in developing a genetically diverse, synthetic population for stock improvement and for identifying potential markers correlated with important commercial traits in GFP. Integration of DNA techniques with traditional breeding practices can facilitate GFP stock improvement in Vietnam and accelerate the industry development when improved lines are available. Some limitations of the current study and recommendations for further work are discussed.
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Cultivo em Massa do Copépodo Bentônico Tisbe biminiensis (Harpacticoida) e Sua Utilização na Larvicultura do Camarão Macrobrachium rosenbergii (Palaemonidae).

Christine Bezerra Ribeiro, Aurelyanna January 2005 (has links)
Made available in DSpace on 2014-06-12T15:05:32Z (GMT). No. of bitstreams: 2 arquivo1797_1.pdf: 494985 bytes, checksum: 49085c55ca04e2212bd3d03cd5d25893 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2005 / Este trabalho teve como objetivos desenvolver técnicas de cultivo em massa do copépodo Tisbe biminiensis em volumes de 5 litros e avaliar o seu desempenho como substituto da Artemia na larvicultura do camarão Macrobrachium rosenbergii. O cultivo do copépodo foi realizado em caixas plásticas (32 x 47 x 14,5 cm) munidas de aeração, com 5 litros de água do mar filtrada, sob temperatura ambiente e salinidade de 35°/oo. O alimento fornecido diariamente foi ração para peixes de aquário e a cada dois dias, nas trocas de água, 500ml das diatomáceas Phaeodactylum tricornutum ou Thalassiosira fluviatilis. Em todos os experimentos o número de copépodos foi estimado por subamostragem. O teste de desempenho do copépodo na larvicultura do M. rosenbergii foi realizado com quatro réplicas para cada um dos cinco tratamentos: 0, 25, 50, 75 e 100% de introdução de copépodo. Os resultados obtidos demonstraram que a coleta semanal de prole e a presença de sedimento arenoso não afetaram o crescimento dos copépodos. Os testes de sustentabilidade dos cultivos demonstraram que T. biminiensis cresceu bem em laboratório mantendo altas densidades por períodos de até 130 dias. O sistema de cultivo produziu uma média de 28.000indivíduos/l/dia A população de copépodos se recuperou 4 dias após a retirada da prole. A substituição da Artemia pelo T. biminiensis não foi favorável a M. rosenbergii, porém as altas mortalidades observadas no controle indicam algum tipo de problema no sistema de cultivo que pode ter influenciado os resultados
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Feeding behaviour of the prawn Macrobrachium rosenbergii as an indicator of pesticide contamination in tropical freshwater

Satapornvanit, Kriengkrai January 2006 (has links)
The purpose of this research was to develop and standardize a novel feeding bioassay with Macrobrachium rosenbergii for use in the laboratory and allowing it to be easily deployed under field conditions. Standardization of the test aimed to minimize feeding rate variations and to ensure that subsequent statistical analyses have sufficient power to consistently detect changes in feeding rates. These were accomplished through the development of a post-exposure feeding toxicity test under laboratory, microcosm and in situ/field conditions. This procedure was proven to be repeatable and economical. M. rosenbergii as test animals were available in terms of quantity and uniformity in sizes. The standard guidelines and procedures for M. rosenbergii bioassay developed from this study include the size of test animals (9-10 mm), density in exposure containers (10 animals in 500 mL of medium in the laboratory, 10 animals in field chambers with 98.6 mL volume), exposure time (24 hours), feeding period for post-exposure feeding (4 hours) and number of replicates for the feeding test (10 replicates for individual measurements). The tiered approach used in the preliminary risk assessment of pesticide using TOXSWA was capable of screening the risk level of pesticide in the study area, identifying profenofos and dimethoate as test chemicals for the lethal and sub-lethal experiments. This model was beneficial in the preliminary risk assessment of pesticides in the tropics, since it was not necessary to set up laboratory work. This method could also provide preliminary data to support the environmental planner and decision/policy maker. This is an alternative way to develop a cost efficient model to inform and warn the risk of pesticide use. The effects of pH, temperature and hardness on control post-exposure feeding rates of M. rosenbergii were assessed and indicated that M. rosenbergii was very sensitive to acidic and basic conditions. The use of post-exposure feeding inhibition as the endpoint under laboratory conditions revealed that prawns were sensitive to pesticides (chlorpyrifos, dimethoate and profenofos) and a heavy metal (zinc). Post-exposure feeding rate inhibition could be used as a sublethal endpoint as the EC50 values obtained for chlorpyrifos and zinc were lower than their lethal levels. Mortality of prawn was also another endpoint used to define the toxicity of pesticides such as carbendazim, in which mortality occurred during exposure, but post-exposure feeding rate of the surviving animals did not decrease. The microcosm experiments were able to link the laboratory toxicity tests and the effects observed in the field. Microcosm studies provided another dimension to studies looking at pesticide effects on aquatic systems. In this research, carbendazim affected feeding and survival rates in the microcosm set-up but in the laboratory only mortality showed a significant difference (P &lt; 0.05). In situ bioassays were able to show the effects of pesticides on post-exposure feeding rates using the methods developed. Post-exposure feeding rates were significantly lower than control in farms using pesticides while in uncontaminated sites (pesticide-free), the post-exposure feeding rates did not decrease. However, mortality was observed even in the uncontaminated sites which could be attributed to other factors such as low dissolved oxygen and presence of some other unidentified chemical substances. The degree of mortality and the effect on feeding rates depends not only on the type and concentration of the known pesticide but also on water quality parameters. The basic methods developed for in situ bioassay from this research is a simple, easy and fast way to determine the effect of pesticides because the results can be seen in the field. The procedures developed and results obtained from this study can be used as a basis for further toxicity studies on M. rosenbergii and other potential tropical species.

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