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Genetic approaches to the analysis of body colouration in Nile tilapia (Oreochromis niloticus)Rajaee, Amy H. January 2011 (has links)
Body colouration in tilapia is an important trait affecting consumer preference. In the Nile tilapia (Oreochromis niloticus), there are three colour variants which are normal (wild type), red and blond. In some countries, the red variant is important and reaches higher prices in the market. However, one major problem regarding red tilapia culture is their body colouration which is often associated with blotching (mainly black but also red) which is undesirable for the consumer. The overall aim of this work was to expand knowledge on various aspects of body colouration in Nile tilapia using genetic approaches. The results of this research are presented as four different manuscripts. The manuscripts (here referred as Papers) have either been published (Paper IV) or are to be submitted (Paper I, II and III) in relevant peer reviewed journals. Paper I and II investigated the inheritance of black blotching and other body colour components of the red body colour. Specifically, Paper I consisted of two preliminary trials (Trial 1 and 2), to look at the ontogeny of black blotching and body colour components over a period of six months. Trial 1 investigated the effect of tank background colour (light vs dark) on black blotching and other body colour components and was carried out using a fully inbred (all female) clonal red line. Trial 2 was carried out using mixed sex fish and was aimed to investigate the association of black blotching with the sex of the fish. The results from this study were used to guide the experiment described in Paper II. Sixteen red sires with various levels of black and red blotching were crossed to clonal females and the inheritance of blotching and other body colour components were investigated using parent-offspring regressions. The results showed no significant heritability for black blotching and body redness, but a significant correlation for body redness and black blotching was found in female offspring at one sampling point suggesting that attempts to increase body redness may increase black blotching, as had been hypothesized. Paper III was divided into two parts. The first objective was to map the blond locus onto the tilapia linkage map and the second was to investigate the interaction of the blond and red genes on black blotching using the blond-linked markers to distinguish different blond genotypes in heterozygous red fish (i.e. RrBlbl or Rrblbl). In the blond fish, the formation of melanin is almost blocked via much reduced melanophores and this feature may be able to help reducing the black blotching in red tilapia. Two intraspecific families (O. niloticus) and one interspecific family (O. aureus and O. niloticus) were used as mapping families and the blond locus was located in LG5. Four out of eight markers were successfully used to assess the interaction of blond on red blotched fish. The blond gene did not significantly reduce the area of blotching but did reduce the saturation (paler blotching) and enhanced the redness of body colour in the Rrblbl fish compared to the RrBlbl group. Finally, Paper IV aimed to find out the effect of male colouration on reproductive success in Nile tilapia. A choice of one wild type male and one red male was presented to red or wild type females and these fish were allowed to spawn under semi-natural spawning conditions. Eggs were collected from the female’s mouth after spawning and paternity was assessed using microsatellite genotyping and phenotype scoring. No significant departures from equal mating success were observed between the red and wild type males, however there was a significant difference between the red and wild type females in the frequency of secondary paternal contribution to egg batches. The results suggest that mating success of wild type and red tilapia is approximately equal. The results from this research help to broaden our knowledge and understanding on the aspects of body colouration in Nile tilapia and provide fundamental information for further research.
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Nutrição e reversão sexual de tilápia do Nilo: parâmetros produtivos e estrutura do fígadoGayão, Ana Laura Borba de Andrade [UNESP] 26 February 2009 (has links) (PDF)
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gayao_alba_dr_jabo.pdf: 596505 bytes, checksum: 4731607f5c25628a3e998a366fe2f3e9 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O estudo teve como objetivo comparar o desempenho produtivo de tilápias do Nilo revertidas ou não por meio da utilização do hormônio 17-α-metiltestosterona (MT) adicionado a dietas práticas e analisar histologicamente o fígado dos peixes. Foram conduzidos quatro experimentos com tilápias do Nilo, da linhagem tailandesa, revertidas ou não revertidas, desde a larvicultura até a engorda em tanques-rede. As dietas utilizadas nos experimentos foram formuladas de forma a assemelharem-se às dietas comerciais utilizadas nas pisciculturas, sendo isocalóricas, variando os níveis e fontes de proteína bruta. Procurou-se simular as causas de fígado gorduroso e friável e mortalidade próxima ao abate de tilápias do Nilo cultivadas em regime intensivo. No primeiro experimento, conduzido com larvas desde a eclosão até 60 dias de idade, observou-se que o nível de 30 mgMT.kg-1 adicionado à dieta, possibilitou eficiência na reversão, melhor desempenho produtivo e menores danos ao fígado que na dosagem de 60 mgMT.kg-1. Nesse mesmo experimento, os peixes que não receberam hormônio tiveram maior taxa de sobrevivência e não mostraram alterações histológicas no fígado. No segundo experimento, a reversão sexual favoreceu o desempenho dos juvenis na fase de recria. Porém, não foi possível observar diferenças no desempenho entre os níveis de proteína da dieta. Um terceiro experimento com tilápias cultivadas em tanques-rede dos 120 aos 600 g de peso, os peixes mostraram melhor desempenho quando alimentados com dieta contendo 32% PB, sendo que o fato de terem passado pelo processo de reversão ou não, não influenciou o desempenho. Um quarto experimento foi realizado concomitantemente ao terceiro em laboratório com juvenis de 30 g até atingirem 200 g e as tilápias revertidas apresentaram... / The aim of the study was compared reversed or no reversed Nile tilapia growth performance and liver histology. Fishes were sex reversed with addition of 17-α- methyltestosterone (MT) at the diets. The study was divided in four experiments: larval phase, growth phase and the final phases in cages and at laboratory. The diets were isocalorics, formulated as commercials diets common used in the Brazil tilapia cultures, utilizing levels and sources protein. The objective was simulated the fat liver problem detected at tilapia farms. In the first experiment, there were used fries until 60 days of culture. There was observed that the level of 30 mgMT.kg-1 conducted to efficiency in the sex reversal with best growth performance and less liver damages than the level of 60 mgMT.kg-1. The fishes that didn’t receive MT reached best survival and didn’t show any liver alteration. In the second experiment, the facts of the fishes were sex reversed increased the growth performance of juveniles. But there was not difference in the growth performance by protein levels. The third experiment conducted at cages, with fishes of 120g until 600g, showed best growth performance when fed with 32% crude protein, but there was no difference by the fact of they were reversed or no. The fourth experiment was conducted at the same time of the third, at laboratory with tilapias of 30g until 200g. The reversed fishes showed best growth performance than the no reversed ones. Alterations of liver histology of the fishes reversed at the four experiments were noted. But there were more severe in the fishes fed with higher levels of crude protein.
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Indicadores de sustentabilidade na avaliação do sistema de cultivo de Tilápia do Nilo em tanques-rede no reservatório de Santa Cruz, Apodi-RN / Sustainability indicators in the evaluation of the Nile Tilapia cage growing system in the Santa Cruz reservoir, Apodi-RNMoura, Rodrigo Sávio Teixeira de 19 December 2014 (has links)
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Previous issue date: 2014-12-19 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The global fish consumption has increased rapidly in recent years and aquaculture contributes increasingly to meet this demand for fish. It is important, however, to establish standards and methods to assess this sustainability in order to analyze the situation of production systems currently in use. The indicators come to be a powerful tool because it allows to obtain a holistic view of the production system in its environmental, social, and economic aspects. Thus, the aim of this study was to evaluate the sustainability of the cage farming system developed in the reservoir of Santa Cruz, Apodi-RN , on their environmental, social and economic aspects . For that were calculated the nutrients and particulate material sedimentation rates in the reservoir, and were used a set of 49 sustainability indicators which were modeled within the Drivers-Pressure-State-Impact-Response (DPSIR) framework. The results indicate that the culture system is economically feasible, generating profit and distributing income, thereby enabling their viability over time. However, the capital generated benefits just a few people, and it is not fixed in the community. Environmentally speaking, the system was inefficient in the use of resources, especially nitrogen and phosphorus, and most of these resources are not incorporated into biomass but sedimented in the reservoir. For the social dimension, the enterprise employs little, generating little direct employment. We realize that fish farming changes the water characteristics of the reservoir, and the indicators used along with the DPSIR modeling were able to satisfactorily reflect these influences / O consumo mundial de pescado vem aumentando rapidamente nos últimos anos e a aquicultura contribui cada vez mais para suprir esta demanda por pescado. É importante, entretanto, estabelecer padrões e métodos para avaliar esta sustentabilidade, a fim de analisar a situação dos sistemas produtivos atualmente em uso. Os indicadores vêm a ser uma ferramenta poderosa, pois permitem obter uma visão holística do sistema produtivo, em suas dimensões ambiental, social, e econômica. Desta maneira, o objetivo deste trabalho foi avaliar a sustentabilidade do sistema de cultivo em tanques-rede desenvolvido no reservatório de Santa Cruz, Apodi/RN, nas suas vertentes ambiental, social e econômica. Para tanto foram calculadas as taxas de sedimentação de nutrientes e material particulado no reservatório, bem como foi utilizado um conjunto de 49 indicadores de sustentabilidade, que foram modelados dentro do arcabouço Drivers-Pressure-State-Impact-Response (DPSIR). Os resultados indicam que o sistema de cultivo é viável economicamente, gerando lucro e distribuindo renda, possibilitando assim sua permanência ao longo do tempo. Entretanto, a renda gerada beneficia poucas pessoas, e não é fixada na comunidade. Ambientalmente falando, o sistema se mostrou ineficiente no uso de recursos, em especial os nutrientes nitrogênio e fósforo, sendo boa parte destes recursos não incorporada em biomassa animal e sedimentada no reservatório. Na dimensão social o empreendimento emprega pouca mão-de-obra, gerando pouco emprego direto. Podemos perceber que a piscicultura altera as características da água do reservatório, e o conjunto de indicadores utilizado juntamente com a modelagem DPSIR foram capazes de refletir de maneira satisfatória estas influências
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Efeitos da remoção da tilápia do Nilo, Oreochromis niloticus (Linnaeus, 1758), na estrutura trófica da ictiofauna em um reservatório do semiárido brasileiro / Effects of removal of Nile tilapia, Oreochromis niloticus (Linnaeus, 1758) in the trophic structure of the ichthyofauna in a Brazilian semiarid reservoirMoura, Cristiane de Carvalho Ferreira Lima 16 December 2014 (has links)
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Previous issue date: 2014-12-16 / This study aimed to analyze the influence of the exotic species Oreochromis niloticus, before and after its removal in the fish assemblage, characterizing its trophic guilds over the months in a
reservoir of the Brazilian semiarid. Data were sampled in two periods, before removal of exotic species (May 2012 to January 2013) and after removal (April 2013 to November 2013). Six
species were analyzed (Oreochromis niloticus, Prochilodus brevis, Hypostomus cf. paparie, Hoplias gr. Malabaricus, Astyanax bimaculatus and Leporinus piau) whose values of the Feeding Index (IAi) were used. The Morisita-Horn similarity coefficient was used to assess the feed similarity between species and establish four trophic categories (insectivorous, omnivorous,
detritophagous / iliófaga and piscivorous). To assess the possible variations due to the presence of the species O. niloticus, we used the Feeding Index of species in Bray-Curtis similarity
matrix, using the ordination analysis (NMDS) that detects if there was difference in items consumed by the species. The result of Multivariate Analysis Canonical Correlation (CCA) between abiotic factors (rainfall, pH, turbidity, dissolved oxygen) and biotic factors showed that the diet is associated with abiotic factors with little correlation with the presence of scavenging /
iliófagas species. The species continued inserted in the same categories, in both periods analyzed, and therefore the number of guilds did not change. It is possible that the species O.
niloticus had no time to settle in the environment during the study period, it is therefore necessary a long-term study to verify the relationship between abiotic factors and the
establishment of tilapia in protected areas / O presente trabalho teve como objetivo analisar a influência da espécie exótica Oreochromis niloticus, antes e após a sua remoção na assembleia de peixes caracterizando suas guildas
tróficas ao longo dos meses em um reservatório do semiárido brasileiro. Os dados foram amostrados em dois períodos, antes da remoção da espécie exótica (maio de 2012 a janeiro de
2013) e após a remoção (abril de 2013 a novembro de 2013. Foram analisadas seis espécies (Oreochromis niloticus, Prochilodus brevis, Hypostomus cf. paparie, Hoplias gr. Malabaricus, Astyanax bimaculatus e Leporinus piau) cujos valores do Índice Alimentar foram utilizados. O índice de Morisita-Horn foi utilizado para avaliar a similaridade alimentar entre as espécies e estabelecer quatro categorias tróficas (insetívora, onívora, detritívora /iliófaga e piscívora). Para
avaliar as possíveis variações devido à presença da espécie O. niloticus, foi utilizado o Índice Alimentar das espécies numa matriz de similaridade de Bray-Curtis, usando a análise de
ordenação (NMDS) que detecta se houve diferença nos itens consumidos pelas espécies. O resultado da Análise Multivariada de Correlação Canônica (CCA) entre os fatores abióticos
(pluviosidade, pH, turbidez, oxigênio dissolvido) e bióticos demonstrou que a alimentação está associada aos fatores abióticos sendo pouco correlacionada com a presença das espécies detritívoras/iliófagas. As espécies continuaram inseridas nas mesmas categorias, nos dois períodos analisados, e portanto o número de guildas não variou. É possível que a espécie O.
niloticus não tenha tido tempo de se estabelecer no ambiente no período estudado, sendo pois necessário um estudo em longa escala para verificar as relações entre os fatores abióticos e o
estabelecimento da tilápia em áreas de proteção ambiental
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Sex determination and genetic management in Nile tilapia using genomic techniquesKhanam, Taslima January 2017 (has links)
The PhD research studied two aspects in tilapia, firstly the analysis of sex determination in Nile tilapia (evidence of complex sex-determining systems) and secondly the genetic management of the tilapia species, using different genomic analysis approaches. This research started with the development of two techniques: minimally invasive DNA sampling from fish mucus, which was found to be suitable for standard genotyping and double-digest restriction-site associated DNA sequencing – ddRADseq; and pre-extraction pooling of tissue samples for ddRADseq (BSA-ddRADseq), which was found to be suitable for identifying a locus linked to a trait of interest (sex in this case). The first molecular evidence concerning the sex determination in genetically improved farmed tilapia (GIFT) was described using BSA-ddRADseq. Given the multiple stock origin of GIFT, surprisingly only a single locus (in linkage group 23) was found to be associated with the phenotypic sex across the population. The first evidence of LG23 influence on phenotypic sex in the Stirling population of Nile tilapia was also found. Different combinations of estrogen hormones and high temperature were tested for feminising Nile tilapia: a combined treatment of estrogen hormone and high temperature was found to be more efficient in feminising Nile tilapia than the estrogen alone. A set of species-diagnostic SNP markers were tested which were found to be suitable to distinguish pure species (O. niloticus, O. mossambicus and O. aureus), and these were used to analyse species contribution to GIFT and a selected tilapia hybrid strain. The results of the current research added novel information to our understanding of sex determination in Nile tilapia, which will be helpful in the development of marker-assisted selection in GIFT and other Nile tilapia strains towards the production of all male offspring. The methods developed also have broader applicability in genetic and genomics research.
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Cultivo de Tilápia do Nilo em esgoto doméstico tratado com diferentes taxas de alimentação / Cultivation of Nile tilapia in sewage treated with different feeding ratesSantos, Emanuel Soares dos January 2008 (has links)
SANTOS, Emanuel Soares dos. Cultivo de Tilápia do Nilo em esgoto doméstico tratado com diferentes taxas de alimentação. 2008. 105 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2008 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-13T12:19:00Z
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Previous issue date: 2008 / The distribution of water is very uneven both in geography and in rainfall throughout the year, making this feature is short of the needs of the population, making us consider the practice of reuse of water as one of the exits to the problems of water supply. This research sought to develop the best methods of cultivation for the implementation of fish farming with the use of treated sewage. It was used nine (09) ponds with 50m ³ of volume each, which were fuelled by domestic sewage treated for the ongrowing of Nile tilapia in three experimental treatments.1° treatment was not offered commercial feed, 2° treatment was offered 50% of the commercial feed suggested by the manufacturer; 3° treatment was offered 100% of the commercial feed suggested by the manufacturer. The following water quality parameters were observed: temperature, pH, OD, nitrite, BOD and COD. From the data collected in biometry, were analyzed the parameters of growth in total length (cm/fish), weight (g/fish), biomass (g/m3) productivity (kg/ha/day) and food conversion rate (CA). All this data were statistically analyzed (ANOVA and Tukey test). Microbiological analyses of produced fish were conducted. Among the parameters of water quality OD and COD showed extremes variations, where OD reached 1.79 mg/l, and COD 494.0 mg/l. For growth in length (cm/fish) treatment 2 presented the best result and is statistically different from the other two treatments. To gain weight (g/fish) the treatment 2 presented again the best result, however, is statistically similar to treatment 1 and 3. For the gain of biomass (g/m) treatment 2 obtained the best result, however, this is statistically similar to the Treatment 1. Treatment 3 showed the worst outcome, as well as productivity and feed conversion. Only a sample of gill showed contamination by Estafilococus Coagulase positive, yet it not makes the consumption of this fish inappropriate. By those findings we concluded that the best treatment to be applied is the cultivation of Nile tilapia with the use of treated domestic sewage is the use of 50% of commercial feed suggested by the manufacturer (treatment 2) / A distribuição de água é muito desigual tanto em geografia quanto em precipitação ao longo do ano, fazendo com que este recurso esteja aquém das necessidades da população. O que nos faz considerar a prática do reúso de águas como uma das saídas para a problemática da oferta hídrica. Esta pesquisa tentou desenvolver a melhor metodologia de cultivo para a aplicação da piscicultura com uso de esgoto tratado. Utilizou-se nove (09) viveiros com 50m³ de volume cada, que foram abastecidos com esgoto doméstico tratado para o cultivo de tilápia do Nilo, em três tratamentos experimentais; 1° Tratamento, não foi ofertada ração; 2° Tratamento, foi ofertada 50% da ração indicada pelo fabricante; 3° Tratamento, foi ofertada 100% da ração indicada pelo fabricante. Foram acompanhados os seguintes parâmetros de qualidade de água: Temperatura, pH, OD, Nitrito e DQO. A partir dos dados colhidos nas biometrias foram analisados os parâmetros de crescimento, em comprimento total (cm/peixe), peso (g/peixe) e biomassa (g/m3); nos quais foi feita a análise estatística ANOVA e o Teste de Tukey; além da produtividade (kg/ha/dia) e taxa de Conversão Alimentar (CA). Foram realizadas análises microbiológicas do pescado produzido. Dentre os parâmetros de qualidade de água o OD e a DQO apresentaram variações extremas, em que, o OD chegou a 1,79mg/l; e a DQO em 494,0 mg/l. Para o crescimento em comprimento (cm/peixe) o Tratamento 2 apresentou o melhor resultado, sendo estatisticamente diferente dos outros dois tratamentos. Para o ganho de peso (g/peixe) o Tratamento 2 apresentou o melhor resultado, porém, é estatisticamente semelhante ao Tratamento 1, que, por sua vez, é semelhante ao Tratamento 3. Para o ganho de biomassa (g/m³) o Tratamento 2 obteve o melhor resultado, porém, este é estatisticamente semelhante ao Tratamento 1, já o Tratamento 3 apresentou o pior resultado; assim como para produtividade e conversão alimentar. Apenas uma amostra de brânquia apresentou contaminação por Estafilococus Coagulase Positiva, o que não inviabiliza o consumo deste pescado. Pelos resultados apresentados concluiu-se que o melhor tratamento a ser aplicado para o cultivo de tilápia do Nilo com uso de esgoto doméstico tratado é aquele em que se utiliza 50% da ração indicada pelo fabricante (Tratamento 2)
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Proposta de tecnologia social para redução do risco de eutrofização em açudes no semiárido / Proposed social technology for risk reduction in semiarid eutrophication in damsRibeiro, Diego Castro January 2013 (has links)
RIBEIRO, Diego Castro.Proposta de tecnologia social para redução do risco de eutrofização em açudes no semiárido. 2013. 122 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Pró-Reitoria de Pesquisa e Pós-Graduação, Programa de Pós-Graduaçãoem Desenvolvimento e Meio Ambiente, Fortaleza-CE, 2013 / Submitted by demia Maia (demiamlm@gmail.com) on 2016-05-10T16:16:03Z
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Previous issue date: 2013 / The deficit in the water balance of the Brazilian Semiarid (BS) makes water the dams vulnerable to the increased concentration of dissolved substances, which could limit or even derail its multiple uses. In addition, several human actions increase the risk of eutrophication of these water bodies. One is the intensive aquaculture, which may contribute to the increase of organic matter. For a sustainable aquaculture production, seeks to use technologies that are both agro-ecological and economic solidarity and promote food security. This study aimed to develop a proposal technology financially viable and socially suitable for fish producing without increasing the risk of eutrophication of dams, source of more than 90% of the water consumed in the BS. This technology makes the consortium with macrophytes in small-scale production of Nile tilapia (Oreochromis niloticus) in ferrocement tanks using recirculated water. The research was conducted in a private rural property, located in Horizonte, Ceará, Brazil, between November 2012 and February 2013. Three modules were constructed using the technology of cultivation ferrocement and low cost materials for recirculation and aeration of the water. Were evaluated the growth performance with stocking density of 30 fish/m³, with three diets: only with commercial feed, with reduced ration in consortium with water hyacinth (Eicchornia crassipes) and with commercial feed and water hyacinth. Was performed financial analysis for the operation of a module simulating a production biannual cultivation of fish with 800 g, were obtained viability indicators, outcome measures and economic sensitivity analysis to changes in prices and market interest. Monitoring of water quality measurements were made in situ and laboratory testing, measuring the main physico-chemical parameters of interest in aquaculture. Were raised the potential characteristics of the system that could take it to the status of social technology as well as its main strengths and weaknesses, and to correlate them with possible environmental damage inherent and comparing them with the impacts of conventional tilapia culture. The module was constructed with two culture tanks ferrocement (creation and filtration), and a water pumping system and other aeration. According to the biometric data, it observed that treatment only with commercial diet is the most suitable, but the water hyacinth are indispensable in the biofilter for maintaining water quality in appropriate conditions. In simulation, the cultivation proved to be feasible (Cost-benefit = 1.84; Point leveling = 31%; Rate of return on capital = 60%) and very stable to changes in prices and market interest (Rate internal return = 101%). Furthermore, this mode of cultivation proved to be very promising as social technology, low risk environment with few resources and used small volume of wastewater generated. Moreover, it represents a source of animal protein and / or low-income families to pay concomitant with preserving the quality of the surface water resources of the BS decreased risk of eutrophication. It can be concluded that it is feasible in tilapia culture tanks ferrocement structure with water recirculation for reuse in construction and easy operation on a small scale. The effective cost of cultivation module (≈ US$ 1.075) is low when considering the benefits of activity for the development of BS, which strengthens aquaculture familiar with sustainable use of natural resources. / O deficit no balanço hídrico do Semiárido Brasileiro (SB) faz com que a água dos açudes da região seja vulnerável ao aumento da concentração de substâncias dissolvidas, podendo limitar ou até inviabilizar seus usos múltiplos. Além disso, diversas ações antrópicas elevam o risco de eutrofização desses corpos d’água. Uma delas é a aquicultura intensiva, que pode contribuir com o acréscimo de matéria orgânica. Para uma produção aquícola sustentável, busca-se utilizar tecnologias que ao mesmo tempo sejam agroecológicas, econômico-solidárias e que promovam segurança alimentar. Este trabalho teve por objetivo a elaboração de uma proposta de tecnologia viável financeiramente e adequada socialmente para produção de peixes sem aumentaro risco de eutrofizaçãodos açudes, fonte de mais de 90% da água consumida no SB. A referida tecnologia consorcia macrófitas aquáticas com a produção em pequena escala de tilápia do Nilo (Oreochromis niloticus) em tanques de ferrocimento com recirculação de água. A pesquisa foi desenvolvida em uma propriedade rural particular, localizada no município de Horizonte/CE, entre novembro de 2012 e fevereiro de 2013. Foram construídos três módulos de cultivo utilizando a tecnologia do ferrocimento e materiais de baixo custo para a recirculação e a aeração da água. Foi avaliado o desempenho zootécnico com densidade de estocagem de 30 peixes/m³, com três regimes alimentares: apenas com ração comercial; com ração reduzida em consórcio com aguapés (Eicchornia crassipes); e com ração comercial e aguapés. Realizou-se a análise financeira para a operação de um módulo de cultivo simulando uma produção semestral de peixes com 800 g, sendo obtidos os indicadores de viabilidade, as medidas de resultados econômicos e a análise de sensibilidade às variações de preços e de juros do mercado. No monitoramento da qualidade de água, foram feitas medições in situ e análises laboratoriais, medindo-se os principais parâmetros físico-químicos de interesse aquícola. Foram levantadas as potenciais características do sistema que pudessem levá-lo à condição de tecnologia social, bem como seus principais pontos positivos e negativos, correlacionando-os com os possíveis danos ambientais inerentes e comparando-os com os impactos da tilapicultura convencional. O módulo de cultivo foi construído com dois tanques de ferrocimento (criação e filtração), além de um sistema bombeamento da água e outro de aeração. De acordo com os dados biométricos, observou-se que o tratamento somente com ração comercial é o mais indicado, mas os aguapés são indispensáveis no biofiltro para a manutenção da qualidade de água em condições adequadas. Em simulação, o cultivo mostrou-se ser viável (Benefício-custo = 1,84; Ponto de nivelamento = 31%; Taxa de remuneração do capital = 60%) e bem estável às variações de preços e de juros do mercado (Taxa interna de retorno = 101%). Além disso, essa modalidade de cultivo mostrou-se bastante promissora como tecnologia social, apresentando baixo risco ao ambiente com poucos recursos utilizados e pequeno volume de efluente gerado. Ademais, representa uma fonte de proteína animal e/ou de renda para famílias de baixa remuneração, concomitante à conservação da qualidade dos recursos hídricos superficiais do SB pela diminuição do risco de eutrofização. Pode-se concluir que é viável o cultivo de tilápias em tanques de ferrocimento, com estrutura de recirculação para reaproveitamento da água de fácil construção e operação em pequena escala. O custo efetivo do módulo de cultivo (≈ R$ 2.150) é baixo quando considerados os benefícios da atividade para o desenvolvimento do SB, que fortalece a aquicultura familiar com uso sustentável dos recursos naturais.
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Tolerance tilápie nilské vůči dusitanům / Tolerance of Nile tilapia to nitritesBROŽ, Pavel January 2013 (has links)
The aim of this thesis was to evaluate the effect of increased concentrations of nitrite to Nile tilapia (Oreochromis niloticus) at different concentrations of chloride. Tilapias adults were exposed for 14 days to nitrite at the concentration of 3 mg.l?1 NO2? (i.e. concentration commonly found in recirculation systems). After 14 days the experimental fishes were divided into 4 group, which differed in concentrations of nitrite and chloride. These groups of fish were held in different conditions for the next seven days. Using standard clinical procedures the following haematologic biochemical parameters were determined: RBC, WBC, Hb, PCV, MetHb, MCV, MCH, MCHC, NO2-, GLU, Ca, Mg, TP, NH3. The tested nitrite concentration was not high enough to cause strong differences of pursued parameters. Only some of them (Hb, MetHb, MCHC) were statistically significant.
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Levedura íntegra e leverura autolisada como pronutriente em dieta para reprodutores de Tílápia do Nilo (Oreochromis niloticus)Signor, Altevir [UNESP] 27 April 2009 (has links) (PDF)
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signor_a_dr_botfmvz.pdf: 560532 bytes, checksum: 83329148a6a5185429d5e4c31d176bfc (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / A composição nutricional da levedura a destaca como alimento funcional. O presente trabalho objetivou avaliar a ação da levedura (Saccharomyces cerevisiae) nas respostas reprodutivas de fêmeas de tilápia do Nilo. No Estudo-I 105 fêmeas da linhagem GIFT foram distribuídas em 15 aquários de 500L (três tratamentos e cinco repetições com sete peixes/aquário). No Estudo-II foram utilizados 63 fêmeas e 21 machos da linhagem GIFT distribuídos em três aquários com capacidade de 7000L de água/cada (21 fêmeas e sete machos/aquário). Em ambos os Estudos, os reprodutores foram alimentados ad libitum com dietas isoprotéica e isoenergética contendo 2,0% de levedura íntegra, 2,0% de levedura autolisada ou ausente de inclusão. O Estudo-I foi realizado na UNESP – AquaNutri, Campus de Botucatu e o Estudo-II foi conduzido no Caunesp - Tilapilcultura Campus de Jaboticabal. Avaliou-se nas fêmeas o desempenho produtivo, status nutricional e composição química das gônadas e, o desempenho reprodutivo e o desenvolvimento inicial das larvas. Os dados foram submetidos à análise de variância e quando significativo aplicou-se o teste de comparações múltiplas de médias. A suplementação de levedura íntegra ou autolisada na dieta das reprodutoras, não melhorou o desempenho produtivo e não influenciou o desempenho reprodutivo das fêmeas. Entretanto, melhorou o desenvolvimento larval 72h após eclosão, com melhor desenvolvimento nas larvas dos reprodutores alimentados com a dieta suplementada com 2,0% de levedura íntegra. / The nutritional composition yeast detach how functional food. The research present objective evaluates the action yeast (Saccharomyces cerevisiae) in the response reproductive of females of Nile tilapia. In Study-I 105 females of GIFT lineage was randomized in 15 500L-aquarius (three treatments and five repetition with seven fish/aquarium). In Study-II was utilized 63 females and 21 males of GIFT lineage was randomized in three 7000L-aquarium (21 female and seven male for aquarium). The spawning was feed ad libitum with diet isoproteic and isoenergetic with 2,0% whole yeast and autolised yeast or supplementation absent. In Study-I were realize in UNESP – AquaNutri Campus de Botucatu and Study-II in Caunesp – Tilapicultura Campus de Jaboticabal. Was evaluation in female productive performance, nutritional status and chemistry composition of gonad (Study-I) and reproductive performance of spawning and development larvae (Study-II). The data was submitted variance analyses and multiple comparison test of mean. The supplemented whole yeast or autolised yeast in diet of spawning didn’t improvement productive performance and didn’t influence reproductive performance of female. Therefore improved of development larvae at 72h after eclosion with improved development in larvae of spawning feed with diet 2,0% whole yeast.
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Assessing insect-based products as feed ingredients for aquacultureDevic, Emilie D. P. January 2016 (has links)
Research has been actively looking for alternative feed ingredients to reduce the reliance of the aquafeed industry on marine ingredients, namely fish meal (FM) and fish oil (FO). In this context, insects, in particular housefly (Musca domestica) and black soldier fly (BSF, Hermetia illucens) larvae, have been identified as promising candidates. Although a global insect farming industry is emerging, it is for now constrained by regulatory and technical bottlenecks that raise the question ‘where and how insect-based products could be integrated into aquaculture’. The literature indicated a high interspecies variability of the results when replacing FM with insect meals in fish diets and previous work failed to consider the existing challenges related to the insect production to demonstrate commercial relevance and applicability. In this thesis, maggot meals (MM) and frass (insect digestate) were assessed as strategic feed ingredients for two commercially important farmed species: Atlantic salmon, (Salmo salar) and Nile tilapia (Oreochromis niloticus), in their relevant contexts. Case studies showed that both housefly and BSF MM are high quality feed ingredients and suitable alternative to FM. Specifically, dietary inclusions of up to 200 g/kg of crude or defatted housefly larvae meal did not compromised the feed digestibility and utilisation and the growth performance and body composition of salmon parr (freshwater stage), compared to a FM-based control diet. Hormone (17α-methyltestosterone) treated diets containing between 250 and 1000 g/kg BSF or housefly meal were found as effective as a commonly used pure hormone-treated FM in sex-reversal process leading to 99.8 to 100% males, high survival and evenness of the fish produced. In a commercial diet for advanced nursing of Nile tilapia fingerlings, up to 80 g/kg BSF meal was included without impairing the fish performance and body composition; dietary inclusion was limited by the lipid content of the crude MM. Finally, BSF frass derived from brewery spent grains or processed food wastes were found more effective when used as soil bio-fertilisers with minimum application rate of 10.0 tonnes/ha or 5.0 tonnes/ha, respectively (for a spring onion culture), rather than supplemental feeds for tilapia farmed in semi-intensive conditions (fertilised pond). The study also indicated that site-specific conditions should be accounted to support appropriate and sustainable use of insect-based products but in any case, juvenile fish should be strategically targeted given their requirements. It is expected that this approach, could support the sustainable intensification of aquaculture and contribute more broadly to food security whilst contributing to the development of a circular economy.
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