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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.
81

Caracterização genética de reprodutores de tilápia : estratégias para a manutenção da variabilidade

SOUZA, Marília Espíndola de 04 June 2007 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-16T14:30:22Z No. of bitstreams: 1 Marilia Espindola de Souza.pdf: 397654 bytes, checksum: b4105af9769e13d8c7922e93537b6014 (MD5) / Made available in DSpace on 2017-02-16T14:30:22Z (GMT). No. of bitstreams: 1 Marilia Espindola de Souza.pdf: 397654 bytes, checksum: b4105af9769e13d8c7922e93537b6014 (MD5) Previous issue date: 2007-06-04 / Tilapia native to Africa, are cultured worldwide. In the past 50 years, populations of Tilapia rendalli have been introduced in Brazil, afterwards Oreochromis niloticus and O. hornorum populations, originated from Ivory Coast, were also imported. In the last ten years, an O. niloticus strain named “Chitralada”, developed in Thailand, completely spread all over the country. One of the populations of O. niloticus named Nilotica that remained from the first imports is being cultured at the Aquaculture Station of Paulo Afonso, representing an unique genetic model. The objective of this study was to investigate the genetic variability and differentiation of two tilapia populations of O. niloticus and O. niloticus “Chitralada” reared in Paulo Afonso Station in order to verify the genetic potentiality of using niloticus population in the construction of a highly inbred strain for further QTL approach or in exploring hybrid vigor. Forty four individuals of each population were genotyped for three microsatellite markers and a total of 22 alleles were found. The mean heterozygosity detected was 0,471 for “Chitralada” population and 0 for the O. niloticus population. The coefficient of genetic differentiation (FST) was 0,627 and the mean inbreeding coefficient(FIS) was 0,309 for Chitralada population and was 1 for O. niloticus population. The absence of heterozygosity in the population of O. niloticus suggests that this population can be used in the development of a highly homozygous strain as well as in obtaining heterosis in crosses with “Chitralada” population. / As tilápias, originárias do continente africano, são cultivadas em todo o mundo. As populações cultivadas no Brasil são derivadas de importações da Tilapia rendalli ,realizadas nos últimos 50 anos, posteriormente da Oreochromis niloticus e da O.hornorum, vinda da Costa do Marfim. Nos últimos 10 anos, a linhagem da O. niloticus chamada de “chitralada”, oriunda da Tailândia, disseminou-se amplamente no país. Uma das raras populações de O. niloticus, remanescente das primeiras importações, é ainda cultivada na Estação de Piscicultura de Paulo Afonso – EPPA, representando um modelo único de isolamento genético. O presente trabalho objetivou avaliar a variabilidade e diferenciação genética de duas populações de tilápia, Oreochromis niloticus e Oreochromis niloticus “chitralada”, ambas cultivadas na Estação de Piscicultura de Paulo Afonso – EPPA, a fim de verificar a potencialidade genética para sua utilização emabordagens voltadas a análise de QTLs, bem como para a exploração de vigor híbrido. Foram genotipados 44 indivíduos de cada população para três marcadores de microssatélite e um total de 22 alelos foram encontrados. A heterozigosidade media observada foi de 0,471 para a população de chitralada, e de 0 para a população denilótica. O coeficiente de diferenciação genética (FST) obtido foi de 0,627, e o valor médio do coeficiente de endocruzamento (FIS) encontrado foi de 0,309 para a população de chitralada, e de 1 para a população de nilótica. A inexistência de heterozigotos na população de O. niloticus sugere que esta população pode ser utilizada na construção de uma linhagem altamente homozigota, como também pode ser explorada para heterose com cruzamentos com a linhagem chitralada.
82

Lesões anatomopatológicas associadas à ocorrência de bacterioses em tilápias (Oreochromis niloticus) de diferentes sistemas de cultivo em Pernambuco/Brasil

PEDROSA, Virgínia Fonseca 27 August 2009 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-22T16:50:48Z No. of bitstreams: 1 Virgina Fonseca Pedrosa.pdf: 303865 bytes, checksum: 420df1fdf37bd4dee6c57213ba1e8f55 (MD5) / Made available in DSpace on 2017-02-22T16:50:48Z (GMT). No. of bitstreams: 1 Virgina Fonseca Pedrosa.pdf: 303865 bytes, checksum: 420df1fdf37bd4dee6c57213ba1e8f55 (MD5) Previous issue date: 2009-08-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The use of methods for identification of agents etiológicos represents an important tool to diagnose illnesses and consequently, to try to minimize the losses caused by the agent's permanence in the fish farmings. In this sense, it was aimed at to associate the lesions anatomopathological with the diversity of bacterias found in collected tilápias of different cultivation systems in Pernambuco. 58 tilápias samples were collected in the summertime period and rainy, that were submitted to analyses anatomopathological and bacteriological, having been observed the occurrence of Aeromonas spp. (29,3%), Vibrio spp. (41,4%) and enterobactérias of the goods Klebsiella spp. (17,2%), Leminorella spp. (1,7%), Obesumbacterium spp. (5,2%), Proteus spp. (1,7%), Providencia spp. (19%), Salmonella spp. (1,7%), Shigella spp. (1,7%) and Taturnella spp. (14%). A significant dependence was detected (p <0,05) of the lesions anatomopathological, with the identified bacterias, as anemic gills, necrosis in the liver and infiltrated eosinofílico in the liver in the animals with Aeromonas spp, lesions in the corporal surface and he/she atrophies in the spleen in the cases with víbrios, lesions in the fins, myocarditis, necrosis in the liver and in the pancreas and infiltrated inflammatory in the liver they were observed in the cases in that enterobactérias of different genders were involved, could be attributed to the unbalance in the atmosphere, contributing in the susceptibilidade of the animals front to these agents opportunists, also existing the possibility of they be associated to the concomitant presence of Aeromonas spp, once there was a significant correlation (p <0,05) in the enterobactérias occurrence and Aeromonas spp. It was verified, through mathematical modelling, that the coming animals of cultivation farms in tank-net, as well as the ones that possess larger corporal total lengths, they presented a better weight earnings. / A utilização de métodos, para identificação de agentes etiológicos, representa uma importante ferramenta para diagnosticar enfermidades e, consequentemente, tentar minimizar as perdas nas pisciculturas. Neste sentido, objetivou-se associar as lesões anatomopatológicas com a diversidade de bactérias encontradas em tilápias coletadas de diferentes sistemas de cultivo em Pernambuco. Foram coletadas 58 amostras de tilápias no período de estio e chuvoso, que foram submetidas à análises anatomopatológicas e bacteriológicas, tendo sido observada a ocorrência de Aeromonas spp. (29,3%), Vibrio spp. (41,4%) e enterobactérias dos gêneros Klebsiella spp. (17,2%), Leminorella spp. (1,7%), Obesumbacterium spp. (5,2%), Proteus spp. (1,7%), Providencia spp. (19%), Salmonella spp. (1,7%), Shigella spp. (1,7%) e Taturnella spp. (14%). Detectou-se uma dependência significativa (p < 0,05) das lesões anatomopatológicas, com as bactérias identificadas, como brânquias anêmicas, necrose no fígado e infiltrado eosinofílico no fígado nos animais com Aeromonas spp, lesões na superficie corporal e atrofia no baço nos casos com víbrios. Nos casos em que estiveram envolvidas enterobactérias de diferentes gêneros, observaram-se lesões nas nadadeiras, miocardite, necrose no fígado e no pâncreas e infiltrados inflamatórios nos fígado, podendo estar atribuídas ao desequilíbrio no ambiente. Esse desequilíbrio pode ter contribuído para a susceptibilidade dos animais frente aos agentes oportunistas, existindo também a possibilidade de estarem associadas à presença concomitante de Aeromonas spp, uma vez que houve uma correlação significativa (p < 0,05) na ocorrência de enterobactérias e Aeromonas spp. Verificou-se por meio de modelagem matemática, que os animais provenientes de fazendas de cultivo em tanques-rede, assim como os que possuem maiores comprimentos corporais, apresentaram melhor ganho de peso.
83

Influência de diferentes densidades de estocagem no desempenho produtivo de tilápia do Nilo Oreochromis niloticus (Linnaeus, 1758) cultivada com tecnologia de bioflocos

WAMBACH, Xélen Faria 26 February 2013 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-23T12:57:54Z No. of bitstreams: 1 Xelen Faria Wambach.pdf: 1001153 bytes, checksum: 42e0ff72f95695d7b5632178ab50ae2f (MD5) / Made available in DSpace on 2017-02-23T12:57:54Z (GMT). No. of bitstreams: 1 Xelen Faria Wambach.pdf: 1001153 bytes, checksum: 42e0ff72f95695d7b5632178ab50ae2f (MD5) Previous issue date: 2013-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Among alternatives of aquaculture production with limited water use for fish farming, the biofloc technology of densities with good production results. Thus, the present study evaluated different stocking densities with biofloc technology, in the nursery and growout phases of Nile tilapia Oreochromis niloticus. The nursery phase lasted 67 days and the tanks were stocked with fingerlings (5.71 g) of tilapia sexually reversed. Treatments consisted of three different stocking densities, with three replicates: 1) D200 (200 fishes.m-3); 2) D350 (350 fishes.m-3) and 3) D500 (500 fishes.m-3). The water quality variables showed no significant difference among treatments (P ≥ 0.05). The best performance was obtained at density of 200 fishes.m-3, with a weight gain of 69.47 g, specific growth rate of 3.71%.day-1, feed conversion ratio of 1.20 and survival of 82.62%. Growout phase lasted 128 days and the tanks were stocked with juveniles (123.3 g) of tilapia using three treatments and four replicates involving different stocking densities: 1) D15 (15 fishes.m-3); 2) D30 (30 fishes.m-3) and 3) D45 (45 fishes.m-3). The best performance was obtained in the density of 45 fishes.m-3, with final weight of 404.37 g, specific growth rate of 0.93%. day-1, survival of 90.97% and feed conversion ratio of 1.6. The use of bioflocs technology presents by itself as a good choice for tilapia intensive production, besides to being a compatible technique with the principles of sustainability, make possible the stocking and productivity of 200 fishes.m-3 with 12.44 Kg.m-3, and 45 fishes.m-3 with 16.57 Kg.m-3, respectively for nursery and growout phases. / Dentre as alternativas de produção aquícola com limitado uso de água para a piscicultura, a tecnologia de bioflocos vem se destacando com bons resultados de produção, possibilitando o aumento de densidades. Assim, o presente trabalho avaliou diferentes densidades de estocagem com tecnologia de bioflocos, nas fases de alevinagem e de engorda, da tilápia do Nilo Oreochromis niloticus. A fase de alevinagem teve a duração de 67 dias e os tanques foram estocados com alevinos (5,71 g) de tilápia sexualmente revertidos. Os tratamentos consistiram de três diferentes densidades de estocagem, com três repetições: 1) D200 (200 peixes.m-3); 2) D350 (350 peixes.m-3) e 3) D500 (500 peixes.m-3). As variáveis de qualidade de água não apresentaram diferença significativa entre os tratamentos (P ≥ 0,05). O melhor desempenho foi obtido na densidade de 200 peixes.m-3, com ganho de peso de 69,47 g, taxa de crescimento específico de 3,71%.dia-1, fator de conversão alimentar de 1,20 e sobrevivência de 82,62%. A fase de engorda teve a duração de 128 dias e os tanques foram estocados com juvenis (123,3 g) de tilápia utilizando-se de três tratamentos e quatro repetições, envolvendo diferentes densidades de estocagem: 1) D15 (15 peixes.m-3); 2) D30 (30 peixes.m-3) e 3) D45 (45 peixes.m-3). O melhor desempenho foi obtido na densidade de 45 peixes.m-3, apresentando peso final de 404,37 g, taxa de crescimento específico de 0,93%.dia-1, sobrevivência de 90,97% e fator de conversão alimentar de 1,6. A utilização da tecnologia de bioflocos apresenta-se como uma boa opção para produção intensiva de tilápia, pois, além de ser uma técnica compatível com os princípios de sustentabilidade, possibilita estocagem e produtividade de 200 peixes.m-3 com 12,44 Kg.m-3, e de 45 peixes.m-3 com 16,57 Kg.m-3, respectivamente para as fases de alevinagem e de engorda.
84

Automação do fornecimento de ração e fracionamento da ração diária para tilápias criadas em ambiente controlado com dieta balanceada / Automation of feed supply and fractionation of daily ration for tilapia grown in controlled environment with balanced diet

Martineli, Gabriel Moreno [UNESP] 16 January 2017 (has links)
Submitted by GABRIEL MORENO MARTINELI null (gabrielmartineli_613@hotmail.com) on 2017-01-30T18:06:25Z No. of bitstreams: 1 Dissertação Gabriel Moreno Martineli.pdf: 625535 bytes, checksum: c498ba925bc09d910344d1f899e4e448 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-03T16:24:19Z (GMT) No. of bitstreams: 1 martinelli_gm_me_bot.pdf: 625535 bytes, checksum: c498ba925bc09d910344d1f899e4e448 (MD5) / Made available in DSpace on 2017-02-03T16:24:19Z (GMT). No. of bitstreams: 1 martinelli_gm_me_bot.pdf: 625535 bytes, checksum: c498ba925bc09d910344d1f899e4e448 (MD5) Previous issue date: 2017-01-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo desde estudo foi avaliar o efeito da frequência alimentar sobre o desempenho produtivo, morfologia intestinal e digestibilidade da proteína de tilápias (Oreochromis niloticus) criadas em ambiente controlado. Para realização do experimento foram utilizadas 180 tilápias da linhagem Supreme com peso médio de 114 ± 1,8g, distribuídas em 18 aquários de 300 litros, com temperatura controlada a 28 ± 0,9 ºC. Todas as tilápias foram microchipadas e cada uma representou uma repetição dentro de cada tratamento experimental. Três frequências alimentares (2, 4 e 24 refeições/dia) ao dia foram testadas, em delineamento inteiramente casualizado com 60 repetições por tratamento. Uma dieta balanceada foi fornecida por alimentadores automáticos, com taxa de alimentação inicial de 4% de peso vivo e a quantidade fornecida ajustada diariamente por Controlador Lógico Programável (CLP). O experimento teve duração de 56 dias. Ao final do período experimental foram avaliados o desempenho produtivo (ganho médio de peso, peso médio final, sobrevivência e conversão alimentar); índices hepatossomático, lipossomático e repleção gástrica, concentração de glicose sanguínea; morfologia intestinal (vilo, profundidade de cripta e relação vilo:cripta) e bromatólogia da carcaça. Os animais alimentados com 24 refeições/dia apresentaram peso médio final e maior ganho médio de peso, menores índices de repleção gástrica, menores níveis de glicose sanguínea e maior relação vilo:cripta. O ensaio de digestibilidade foi realizado após o período de 56 dias e teve duração de sete dias. Para determinação do coeficiente da digestibilidade aparente da proteína os peixes fora alimentados com a mesma dieta balanceada, marcadas com 0,1% de óxido crômio III, e coleta de fezes por decantação. Não houve diferença entre três frequências alimentares avaliadas para os coeficientes da digestibilidade aparente da proteína. Com base nos resultados conclui-se que o fracionamento da porção diária em 24 refeições/dia diminui a sobrecarga gástrica e influenciou no maior ganho médio de peso das tilápias. / The objective of this study was to evaluate the effect of dietary frequency on the productive performance, intestinal morphology and digestibility of tilapia protein (Oreochromis niloticus) grown in a controlled environment. For the experiment, 180 tilapia of the Supreme lineage with an average weight of 114 ± 1.8g were used, distributed in 18 aquariums of 300 liters, with controlled temperature at 28 ± 0,9 ºC. All tilapia were microchipped and each represented one replicate within each experimental treatment. Three feeding frequencies (2, 4 and 24 meals / day) per day were tested in a completely randomized design with 60 replicates per treatment. A balanced diet was provided by automatic feeders, with initial feed rate of 4% live weight and the amount supplied adjusted daily by Programmable Logic Controller (CLP). The experiment lasted 56 days. At the end of the experimental period, the productive performance (mean weight gain, final mean weight, survival and feed conversion) were evaluated; Hepatosomatic, liposomal and gastric repletion indexes, blood glucose concentration; Intestinal morphology (villus, depth of crypt and relation villus: crypt) and carcass bromatology. Animals fed with 24 meals / day presented mean final weight and weight gain, lower rates of gastric repletion, lower blood glucose levels and higher villus: crypt ratio. The digestibility assay was performed after the 56 day period and lasted seven days. For determine the coefficient of apparent digestibility of the protein, the fish were fed the same balanced diet, labeled with 0.1% chromium oxide III, and fecal collection by decanting. There was no difference between three food frequencies evaluated for the coefficients of protein apparent digestibility. Based on the results, it was concluded that fractionation of the daily portion at 24 meals / day decreased gastric overload and influenced the higher average weight gain of tilapia.
85

Suplementação alimentar com 'beta'-glucano e mananoligossacarídeo para tilápias do Nilo em tanques-rede /

Garcia, Fabiana. January 2008 (has links)
Orientador: Flávio Ruas de Moraes / Banca: Luiz Edivaldo Pezzato / Banca: Newton Castagnolli / Banca: Laura Satiko Okada Nakaghi / Banca: Sérgio Henrique Canello Schalch / Resumo: o objetivo deste estudo foi avaliar a aplicabilidade do modelo de crescimento exponencial no estudo da eficiência da suplementação alimentar com mananoligossacarídeo e 'beta'-glucano para tilápias do Nilo criadas em tanques-rede. O experimento foi realizado em piscicultura de criação de tilápias em tanques-rede, no município de Zacarias, SP. Foram utilizadas tilápias jovens, com peso inicial de 25,4 ± 2,04 g, distribuídas em 12 tanques-rede de 2 x 2 x 1,5 m, com volume útil de 6 m3 e densidade de 2500 peixes por tanque. Para estudo das curvas de crescimento, realizou-se a biometria individual de uma amostra aleatória de 5 % dos peixes de cada unidade experimental. Os resultados do presente estudo permitem concluir que a adição de 2000 mg de suplemento/kg de ração incrementa a taxa de crescimento de tilápias do Nilo criadas em sistema de tanques-rede e que o modelo de curvas exponenciais pode ser usado para comparar a eficiência de diferentes dietas em estudos de nutrição de peixes. / Abstract: The aim of this study was to evaluate the exponential growth model applicability to study feed supplementation efficiency with mannan oligosaccharide and 'beta'-glucan in Nile tilapia raised in net cage. The trial was carried out in a cage fish farm, at Zacarias city, SP. Juveniles tilapia (initial weigh 25,4 ± 2,04 g) were distributed in 12 cages (2 x 2 x 1,5 m), with 6 m3 volume and stock density of 2500 fish per cage. To evaluate the exponential growth model, a randomized sample of 5 % fish was collected for individual biometry in each experimental unit. The results show that 2000 mg of supplement/kg diet increase the growth ratio of Nile tilapias raised in net cage and the exponential growth model can be used to compare efficiency of different diets in nutrition studies. / Doutor
86

Effet de l’alimentation à base d’Azolla sur la production du tilapia du Nil en zones humides au Bénin Effect of feeding with Azolla on production of Nile tilapia in Benin wetlands

ABOU, Youssouf 19 December 2007 (has links)
Résumé Une meilleure intégration de la fougère aquatique Azolla dans les aliments de O. niloticus en vue de sa production en milieu rural a été recherchée en bassins et en étangs. Six aliments (29,2 % PB; 16,9 kJ g-1 EB, chacun) : A0, A10, A20, A30, A40 et A50 contenant respectivement 0, 10, 20, 30, 40 et 50 % de farine d’Azolla (FA) en remplacement partiel de la farine de poisson ont été testés. En bassins comme en étangs, une réduction de la croissance a été enregistrée lorsque la teneur en FA a dépassé 10 et 20 % respectivement. En étangs, les valeurs de production piscicoles (8220-5120 kg ha-1 an-1) et d’indice de profitabilité (0,42-0,89) sont similaires jusqu’à 20 % et 30 % de FA dans les aliments. L’élevage en étangs pourrait être plus avantageux en nourrissant les poissons avec A20 en étangs dont la surface est couverte à 45 % par un tapis d’Azolla. Dans les deux systèmes d’élevage, la composition des carcasses ne semble pas être affectée, excepté une réduction de la teneur en lipides totaux dans les poissons nourris avec A30, A40 et A50 en bassins et ceux nourris avec A50 en étangs. D’un point de vue environnemental, malgré que la teneur en phosphore des aliments soit passée de 1,13 % à 0,76 % en faisant varier leur teneur en Azolla de 0 % à 50 %, les compositions en phosphore (P) et azote (N) des poissons sont similaires, en bassins comme en étangs. En bassins, les quantités de P et de N rejetées par les poissons ont diminué avec l’augmentation de FA dans les aliments. De même, la quantité de P rejetée en étangs décroît, tandis que celle de l’azote est identique dans tous les traitements. La composition en acides gras des poissons élevés en bassins ressemble à celle des aliments, excepté une augmentation de la teneur en acide arachidonique (ARA) chez les poissons nourris à fort taux d’Azolla. Ceci pourrait être le fait d’une élongation et désaturation de l’acide linoléique. Les valeurs du ratio n-3/n-6 (0,08-0,17) qui en résultent sont faibles chez les poissons nourris avec A40 et A50. Le profil en acides gras des poissons d’étangs est par contre différent de celui des poissons de bassins et de la composition des aliments. Cette dissemblance est particulièrement prononcée chez les poissons nourris avec A30, A40 et A50 qui sont riches en acide éicosapentaénoique (EPA) et acide docosahexaénoique (DHA), principaux acides gras dans le plancton. Cette "signature" du plancton pourrait être due à une consommation supplémentaire de ces nourritures naturelles par ces poissons et expliquerait les valeurs élevées du ratio n-3/n-6 (0,35-0,53) dans les poissons nourris avec les aliments contenant 20 à 50 % de FA. Les paramètres de croissance et le profil en acides gras sont meilleurs en étangs qu’en bassins, et les nutriments rejétés en étangs sont relativement faibles, probablement à cause de la contribution de la nourriture naturelle. En conclusion, Azolla pourrait permettre de réduire le coût des aliments et le coût total de production des poissons, tout en garantissant un bon niveau trophique des étangs et une bonne qualité nutritionnelle des poissons produits. L’étude suggère d’utiliser la fougère jusqu’à 10 % dans les aliments en bassins et 20 à 30 % en étangs. Dans ce dernier système, une couverture des étangs de maximum 45 % de leur surface pourrait permettre de produire des poissons, en même temps qu’elle fournirait de l’Azolla à incorporer dans les aliments ou pour d’autres utilisations bénéfiques. Abstract An improved integration of the aquatic fern Azolla in diets for production of Nile tilapia O. niloticus in rural area was investigated in tanks and in ponds. Six diets (29.2% CP; 16.9 kJ g-1 GE, each) were tested, containing 0% (diet A0), 10% (diet A10), 20% (diet A20), 30% (diet A30), 40% (diet A40) and 50% (diet A50) of Azolla meal (AM) as fishmeal (FM) substitutes. The diet A0 served as a control. Growth parameters decreased, significantly when Azolla level exceeds 10% and 20% in diets, respectively in tanks and ponds. In ponds, the variation of annual fish production follows the trend in growth parameters, with values decreasing from 8220 to 5120 kg ha-1 year-1. Identical profitability index (range: 0.42-0.89) was obtained up to 30% Azolla. Feeding with A20 could be more advantageous by rearing fish in ponds covered with Azolla mat at a maximum of 45% of the water surface. In tanks and in ponds, fish carcass was not significantly affected, except for the total lipid content of fish fed 30, 40 and 50% Azolla in tanks, and those fed 50% Azolla in ponds. From an environmental point of view, phosphorus and nitrogen contents in experimental fish show similar values, both in tanks and ponds, although phosphorus content in diets varied from 1.13% to 0.76% when Azolla level increased from 0% to 50%. In tanks, phosphorus (P) and nitrogen (N) discharged as wastes by fish decreased with increasing Azolla level in diets. Also, P decreased significantly in ponds whereas identical values were found for nitrogen in all treatments. In tanks, fish fatty acids mirror the profile in diets, except for the high arachidonic acid content (ARA) in high AM-fed fish, probably as a result of elongation and desaturation of linoleic acid. This leads to a lower n-3/n-6 ratio (range: 0.08-0.17) in fish fed A40 and A50. Fatty acid composition of fish fed in ponds was different from that in fish fed in tanks, and from diets. The lower resemblance of fish composition was more pronounced in fish fed A30 to A50 in which large amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were found, reflecting closely the composition in plankton. The reason could be a supplemental consumption of plankton by those fish as a response to the deficiency in diets A30-A50. Then, the n-3/n-6 ratios (range: 0.35-0.53) were higher in fish fed A20 to A50. Growth and fatty acid composition were better in ponds, and nutrients loading into pond water were lower, probably due to the contribution of natural foods. In conclusion, Azolla use leads to reduced feed and total fish production costs, while ensuring a suitable pond trophic level and a good nutritional quality of the fish produced. The study suggests using Azolla in tanks up to 10% in diets, while up to 20-30% can be recommended in ponds. In the latter case, covering the ponds surface with Azolla mat at a maximum of 45% of its surface could lead to produce fish, while ensuring Azolla mass production for diets and other beneficial utilization.
87

Study on the oxygen tolerance of milkfish (Chanos chanos), mullet (Liza macrolepis) and Tilapia (Oreochromis mossambicus)

Wang, Tian-Yuan 19 July 2003 (has links)
Dissolved oxygen (DO) level is a critical factor for the survival of fishes and sustainable management of an aquatic ecosystem. This study aims to investigate the lethal thresholds of three major fish species in the Love River, Kaohsiung, S. W. Taiwan, in an attempt to provide ecological points of view for the further improvement of the river-water quality, as well as for the restoration of its fish community. Laboratory tolerance experiments of fish fries, including mullet (Liza macrolepis), milkfish (Chanos chanos) and tilapia (Oreochromis mossambicus), exposed to low levels of dissolved oxygen were conducted in the period of January 2002 to April 2003. At water temperature of 23¢J, median lethal times (LT50) and 48 hours median lethal concentrations (48h LC50) at the salinity of 10‰, 20‰ and 30‰ were determined, respectively. We also carried out a lethal DO experiment to mullet fry in a sudden drop of salinity from 30‰ to 20‰, which is always the case when the sewage gate of the Love River interception system is opened to avoid flooding after heavy rainfall. Under the condition of 20‰ salinity, the tolerance of low dissolved oxygen for the three species of fish fries were significantly different. Among them, milkfish was found to be the most sensitive species, followed by mullet, whereas tilapia was the most tolerant species. The 48h LC50s of milkfish, mullet and tilapia were 15.7, 8.6 and 7.8% air saturation, respectively, which were 1.16, 0.63 and 0.57 mg/l at 23¢J. Similarly, the LT50s also showed species-specific differences. At DO level of 0.52 mg/l, the LT50s were 77.9 minutes for milkfish, 245.7 minutes for mullet and over 1000 minutes for tilapia. The changing of salinity affecting the tolerance of low dissolved oxygen in fish fries was species depending. The DO lethal concentrations of mullet fry increased with the decrease of salinity, but not the case for milkfish fries. The 48h LC50 of mullet fries in 30‰ saline water was 11.5% air saturation (0.8 mg/l), which was higher than those in 10‰ and 20‰ saline water. However, no significant difference in 48h LC50 was found between milkfish kept in 10‰ and 20‰ saline water. The 48h LC50 for the former was 14.9% air saturation while the latter was 15.7%. Both are equivalent to 1.16 mg/l at water temperature of 23¢J. A rapid change of salinity reduced the low Do tolerance of fish fry. When mullet fry were introduced to 20‰ saline water from acclimated salinity of 30‰, its 48h LC50 raised significantly (13.9% air saturation; 1.02 mg/l). Under the DO concentration of 0.52 mg/l, the LT50 also dropped to 7.6 minute. It means that the opening of sewage interception gate largely challenges the survival fish fry. Based on the results of current study, the DO level of Love River is suggested to be maintained beyond 2.19 mg/l (28 % air saturation, 48h LC50 of milkfish at 10‰ salinity and 23¢J water temperature), in order to achieve a sustainable environment for the present fish community. In case of that DO occasionally fall to the above level, it is strongly recommended that a manual aeration system should be operated within 100 minutes.
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Avaliação in situ da biogeodisponibilidade de metais em área de mineração usando as técnicas de peixes transplantados e DGT / In situ evaluation of the biogeoavailability of metals in a mining area using transplanted fishes and DGT techniques

Eismann, Carlos Eduardo [UNESP] 14 November 2017 (has links)
Submitted by CARLOS EDUARDO EISMANN null (kadueismann@gmail.com) on 2018-01-05T14:55:15Z No. of bitstreams: 1 Dissertação Carlos Eduardo Eismann.pdf: 1179566 bytes, checksum: 31c2f0993986aed5992b2088ac3153cb (MD5) / Rejected by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br), reason: Prezado Carlos Eduardo Eismann, Solicitamos que realize uma nova submissão seguindo as orientações abaixo: - Capa - Faltou a capa no documento enviado. - Folha de Aprovação (faltou) Estes itens são elementos obrigatórios de acordo com as normas de trabalhos do seu Programa de Pós Graduação. Agradecemos a compreensão e aguardamos o envio do novo arquivo. Atenciosamente, Biblioteca Campus Rio Claro Repositório Institucional UNESP on 2018-01-08T18:12:45Z (GMT) / Submitted by CARLOS EDUARDO EISMANN null (kadueismann@gmail.com) on 2018-01-09T12:39:53Z No. of bitstreams: 1 Dissertação Carlos Eduardo Eismann.pdf: 1285572 bytes, checksum: b10940da816026c45e4e6fa92a5d4807 (MD5) / Approved for entry into archive by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br) on 2018-01-09T18:37:35Z (GMT) No. of bitstreams: 1 eismann_ce_me_rcla.pdf: 1252029 bytes, checksum: 63e1b3228ec61f7168a0ff587899bcec (MD5) / Made available in DSpace on 2018-01-09T18:37:35Z (GMT). No. of bitstreams: 1 eismann_ce_me_rcla.pdf: 1252029 bytes, checksum: 63e1b3228ec61f7168a0ff587899bcec (MD5) Previous issue date: 2017-11-14 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A toxicidade e biodisponibilidade dos metais presentes no ambiente estão diretamente relacionadas com as suas condições de especiação. A avaliação in situ da biogeodisponibilidade de metais é uma ferramenta importante na manutenção da qualidade ambiental dos sistemas aquáticos. A técnica DGT (do inglês Diffusive Gradient in Thin Films) e o uso de animais transplantados são capazes de fornecer informações desta natureza. As biodisponibilidades de Al, Fe, Mn e Zn em águas de três pontos no interior de uma área de mineração desativada no município de Caldas-MG, Brasil, foram avaliadas utilizando-se a técnica DGT e exemplares transplantados do peixe Oreochromis niloticus. As amostragens foram realizadas em períodos de 14, 28 e 42 dias. Foram utilizados dispositivos DGT com géis difusivos e restritivos e foram determinadas as concentrações de Al, Fe, Mn e Zn nos fígados, brânquias e músculos dos peixes após digestão ácida em microondas. As determinações das concentrações dos analitos nas amostras foram realizadas por Espectrometria de Emissão Óptica com Plasma acoplado Indutivamente (ICP-OES). A massa acumulada nos dispositivos com géis restritivos foi maior que com os géis difusivos, indicando uma possível contribuição da fração moderadamente lábil na massa acumulada nos dispositivos. Os resultados da DGT indicaram uma presença de concentrações muitos baixas de espécies orgânicas destes elementos em todos os pontos estudados. As maiores frações de Al, Fe, Mn e Zn foram identificadas nos pontos 014, 023, 023 e 041 respectivamente. O método proposto se mostrou satisfatório para determinar as concentrações de Al, Fe, Mn e Zn em todas as amostras dos tecidos de O. niloticus. Foram observados incrementos significativos nas concentrações de Mn e Zn nas brânquias dos exemplares transplantados quando comparados com aqueles não transplantados. As concentrações lábeis foram mais satisfatórias do que as concentrações dissolvidas em predizer a variabilidade espacial das concentrações biodisponíveis de Al, Fe, Mn e Zn. / The toxicity and bioavailability of metals in the environment is directly associated to its speciation conditions. The in situ evaluation of the biogeoavailability of metals is an important tool to support the environmental quality of aquatic systems. The DGT technique (Diffusive Gradients in Thin Films) and the use of transplanted animals are able to give this kind of information. The bioavailability of Al, Fe, Mn and Zn was evaluated at three points inside a disabled uranium mining site at Caldas city, Brazil, using DGT technique and transplanted specimens of the fish Oreochromis niloticus. The samplings were performed in periods of 14, 28 and 42 days. The DGT devices were deployed using diffusive and restrictive gels and the Al, Fe, Mn and Zn concentrations were determined at the kidney, gill and muscle of the fishes after an acid digestion using a microwave. The determinations of the analytes were performed by Inductively Coupled Plasma Optic Emission Spectrometry (ICP-OES). The accumulated mass in the devices using restrictive gels was higher than using diffusive gel, indicating that there’s probably a contribution of the moderately labile fractions to the accumulated mass of these devices. Results from DGT indicated the presence of very low concentrations of organic species of Al, Fe, Mn and Zn in all the sampling points. The highest labile fraction of Al, Fe, Mn and Zn were observed at points 014, 023, 023 e 041 respectively. The proposed method was satisfactory in determining the concentration of Al, Fe, Mn e Zn in all the tissue samples of O. niloticus. A significant increase of the Mn and Zn concentrations was observed in the gills of the transplanted specimens when comparing to the not transplanted ones. The labile concentrations were more satisfactory predicting the spatial variability of the bioavailable Al, Fe, Mn and Zn concentrations than the dissolved concentrations.
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Mananoligossacarídeo e β-glucano na suplementação dietária para juvenis de tilápia-do-nilo mantidos em tanques-rede

Sousa, Andressa Daniela Liranço de [UNESP] 04 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-04Bitstream added on 2014-06-13T20:40:29Z : No. of bitstreams: 1 sousa_adl_dr_jabo.pdf: 988790 bytes, checksum: 16a6c08389c72bdf340f861f5412e6be (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Este experimento foi conduzido em um empreendimento aquícola, tendo como objetivo a utilização de mananoligossacarídeo (MOS) e ß-glucano, na suplementação dietária do lote experimental, com o intuito de acompanhar o desempenho zootécnico e relacioná-lo aos parâmetros hematológicos, alterações morfológicas do intestino e atividade enzimática (protease, lípase e amilase) de 3000 juvenis de tilápias-do-nilo, mantidos em tanques-rede, com peso médio inicial de 24g ± 0,26. Utilizaram-se nove tanques-rede (6,0 m3) constituindo-se de três tratamentos e três repetições: Tratamento 1: ração comercial sem suplementação (controle); Tratamento 2: 0,1% por tonelada de MOS; Tratamento 3: 0,03% por tonelada de beta glucano purificados. A ração continha 36 % de proteína bruta (PB), incorporados no premix MOS e β-glucano purificado (BIORIGIN®). Os exemplares foram alimentados três vezes ao dia de acordo com a sua biomassa, e, mensalmente, os ajustes foram determinados de acordo com as biometrias. Os parâmetros analisados, físicos e químicos da água (temperatura, °C, oxigênio dissolvido, mg L-1, pH e condutividade elétrica, us cm-1); zootécnicos (peso inicial e final - Pti e Ptf, comprimento total inicial e final - Cti e Ctf, relação Pi x Ct,, fator de condição - K, conversão alimentar aparente -CAA, ganho de peso diário - GPD, taxa de crescimento específico - TCE, taxa de eficiência protéica - TEP e sobrevivência – S); hematológicos (hematócrito, hemoglobina, proteína total, contagem diferencial de leucócitos - CDL, contagem de eritrócitos - Er, contagem total de leucócitos - CTL, contagem total de trombócitos - CTT, volume corpuscular médio e concentração -VCM e hemoglobina corpuscular média – CHCM); morfologia da parte anterior do intestino (altura, altura da parede e espessura do epitélio das vilosidades) e atividade enzimática... / This experiment was conducted at an aquicolous enterprise with the objective of evaluating the use of mannanoligosaccharide (MOS) and ß-glucan as dietary supplements in an experimental lot in order to follow the zootechnical performance, establishing a relationship with the hematological parameters, the morphological alterations of the intestine, and the enzymatic activity (protease, lipase and amylase) of 3000 Nile tilapia juveniles kept in cages, with initial mean weight of 24g ± 0.26. Nine net tanks (6.0 m3) were used, with three treatments and three replications: Treatment 1: commercial feed without supplementation (control); Treatment 2: 0.1% per ton of MOS; Treatment 3: 0.03% per ton of purified beta glucan. The feed contained 36 % of crude protein (CP) incorporated into the premix MOS and purified beta glucan (BIORIGIN®). The fishes were fed three times a day according to their biomass, where the adjustments were determined monthly according to the biometry. The analysed parameters were: physical and chemical parameters of the water (temperature, °C, dissolved oxygen, mg L-1, pH and electrical conductivity, us cm-1); zootechnical (initial and final weight - Wti and Wtf, initial and final total length - Lti and Ltf, relationship Wi x Lt, condition factor - K, apparent feed-conversion - AFC, daily weight gain - DWG, specific growth rate - SGR, protein efficiency ratio - PER and survival rate - S); hematological; (hematocrit, hemoglobin, total protein, leucocyte differential count - LDC, red blood cell count - RBC, total leucocyte count - TLC, total thrombocyte count - TTC, mean corpuscular volume - MCV, and mean corpuscular hemoglobin concentration – MCHC); morphology of the front part of the intestine (height, height of the wall and thickness of the epithelium of the villi) and enzymatic activity (protease, lipase e amylase). The nile tilápia that had received the diet... (Complete abstract click electronic access below)
90

Toxicidade aguda e crônica do permanganato de potássio em Orechromis niloticus, Ceriodaphnia dubia e Pseudokirchneriella subcapitata

França, Jakeline Galvão de [UNESP] 29 July 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-29Bitstream added on 2014-06-13T20:21:11Z : No. of bitstreams: 1 franca_jg_dr_jabo.pdf: 2251025 bytes, checksum: 4391181f6db61217e2ad4bea2e7f55fd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O objetivo deste estudo foi avaliar o potencial tóxico do permanganato de potássio (KMnO4) através da avaliação da toxicidade aguda (CL50;96 h) e crônica para a tilápia, Oreochromis niloticus e a ecotoxicidade desse composto através de ensaios com o microcrustáceo Ceriodaphnia dubia e com a microalga Pseudokirchneriella subcapitata. Para o teste de toxicidade aguda foram utilizados alevinos de tilápia (0,52 + 0,10g e 3,35 + 0,36 cm), expostos a seguintes concentrações: 0; 0,5; 1,0; 2,0; 4,0 e 6,0 mg.L-1 KMnO4. Os efeitos subletais do KMnO4 foram avaliados pelo do teste de toxicidade crônica, com um grupo controle e duas concentraçõesteste, utilizadas na aqüicultura para o manejo e controle de doenças (1,0 e 4,0 mg.L-1 KMnO4). Para este teste foram utilizadas tilápias (40 g) jovens, expostas por 30 dias, com amostragem de 10 indivíduos por tratamento, nos intervalos de 0, 7, 15 e 30 dias. Os biomarcadores avaliados no presente estudo foram: análises hematológicas, da atividade fagocítica, determinações da concentração de GSH, da atividade enzimática da GST, catalase e peroxidação lipídica e genótoxicas. No teste de toxicidade aguda, o baixo valor de CL50;96h (1,81 mg.L-1), sugere que esta espécie de peixe, nesta fase de desenvolvimento, apresenta grande sensibilidade ao composto. No teste de toxicidade crônica, os peixes expostos na concentração de 1 mg.L-1 de KMnO4 não apresentaram variações significativas nos parâmetros sanguíneos analisados quando comparados ao grupo controle. Na concentração de 4 mg.L-1, as alterações no quadro hematológico indicaram processo de hemólise e redução da atividade fagocítica em consequência da ação oxidante do KMnO4. Nas concentrações de 1 e 4 mg.L-1 KMnO4 houve redução significativa da capacidade fagocítica de macrófagos. Na análise bioquímica, somente a enzima GSH apresentou aumento significativo... / This study aimed know the toxic potential of the potassium permanganate (KMnO4) through the evaluation of the acute (LC50;96h) and cronic toxicity to tilapia, Oreochromis niloticus and the ecotoxicity of this compound through the assays with the microcrustacean Ceriodaphnia dubia and with microalgae Pseudokirchneriella subcapitata. For the acute toxicity test were used tilapia fingerlings (0.52 + 0.10g and 3.35 + 0.36 cm), exposed to concentrations: 0; 0.5; 1.0; 2.0; 4.0 and 6.0 mg.L-1 KMnO4. The sublethal effects of the KMnO4 were evaluated through cronic toxicity test, with a control group and two test concentrations, used in the aquaculture to management and control fishes diseases (1.0 and 4.0 mg.L-1 KMnO4). To this experiment were used with juvenile tilapia (40 g), exposed for 30 days, with samples of 10 individuals from each treatment at intervals of 0, 7, 15 and 30- days. The biomarkers evaluated in this present study were: hematological analysis, phagocytic activity, determination of GSH concentration, of enzymatic activity of GST, catalase, lipid peroxidation and genotoxities. In the acute toxicity test, the low value of LC50;96h (1.81 mg.L- 1), suggests that this species of fish, in this phase of development, it presents the great sensitivity to the KMnO4. In the cronic toxicity test, the fishes exposed in the concentrations of 1 mg.L-1 de KMnO4 did not present significant variations in the analyzed sanguineous parameters when compared with the control group. In concentration of 4 mg.L-1 the hematological alterations indicated process of hemolysis and immunosuppression in consequence of the oxidant action of KMnO4. In the immunologicals analysis, the concentrations of 1 and 4 mg.L-1 KMnO4 had significant reduction of the fagocitic capacity of the fishes suggesting suppression of the immune system. In the analysis biochemical, only the enzyme GSH presented significant increase... (Complete abstract click electronic access below)

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