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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.
51

Consequências das condições de escolha no crescimento e interações agonísticas da tilápia-do Nilo, Oreochromis niloticus

Silva, Fernanda Pereira Corbeira da [UNESP] 22 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-22Bitstream added on 2014-06-13T18:40:08Z : No. of bitstreams: 1 silva_fpc_me_botib.pdf: 1084579 bytes, checksum: 1fb89febed5a599309115db07175a010 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Not available
52

Salga, prensagem da tilapia do Nilo(Sarotherodon niloticus)

Henao Cuellar, Jose Duban 16 September 1988 (has links)
Orientadores : Jose Luis Vasconcellos Rocha, Emilio Contreras Guzman / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-07-15T08:00:23Z (GMT). No. of bitstreams: 1 HenaoCuellar_JoseDuban_M.pdf: 5324029 bytes, checksum: e23c213a8262a9076f5cb726ba83625d (MD5) Previous issue date: 1988 / Mestrado / Agua e Solo / Mestre em Engenharia Agrícola
53

An investigation into the dietary requirements of Oreochromis Mossambicus fry and the formulation and preparation of a dry food for use in aquaculture

Thorpe, Peter Stuart January 1989 (has links)
The need for developing a dry feed which satisfied the nutrient requirements of Oreochromis mossambicus fry was identified. The spawning and grading techniques which resulted in a higher fecundity and ensured uniformity within and between samples of fry are discussed. Preparation techniques were developed which met the physical requirements of fry feeds. An analysis of the flesh and yolk sac fry for amino acid composition was undertaken. The initial test diet was based on these results, as well as on the natural feeding ecology of the species. Feeding trials were undertaken and growth responses monitored to determine the optimum levels of the various dietary components. A feed was developed which gave superior growth to that obtained with natural food organisms. This feed consisted of Torula yeast (47%), Weider Super Protein (44.39%), Vitamin supplement (0.45% - multivitamin), additional vitamin C supplement (0.16%), Spirulina (5%), and methionine supplement (3%). An optimum particle size range for O. mossambicus fry (between 5 & 25mm) was established at 125-200um. The fry should be fed the following feed ratios depending on age: 30.4% body weight/day up to day 5, 30.6% body weight/day up to day 10 and 25.1% body weight/day up to day 15. An optimum feeding frequency of 8/10hr day was recommended. A feed conversion ratio of 1.24:1 and a protein efficiency ratio of 0.682:1 was obtained. Digestable energy of the feed was determined at 16.1 kj/g feed. The established dry feed is suitable for use in commercial hatcheries, and as a formulation for further research on the intensive rearing of O. mossambicus fry.
54

The effect of the pesticide, endosulfan, on hepatic cytochrome P-450, liver and gill ultrastructure, and selected haematological parameters of Oreochromis Mossambicus (Peters, 1852) (Pisces : Cichlidae)

Quick, Arthur Joseph Rex January 1986 (has links)
Two possible ways in which fish may acclimate to prolonged exposure· to sublethal levels of endosulfan were investigated: induction of the hepatic monooxygenase system and changes in haematology. These studies also involved an examination of the ultrastructure of liver and gill tissue. Endosulfan caused none of the characteristic phenobarbital-type inductive effects on the liver of Oreochromis mossambicus. There was no increase in cytochrome P-450 levels, microsomal protein or hepatosomatic index. The reasons for the lack of induction are discussed. The effect of endosulfan on the following haematological parameters was determined: haemoglobin, erythrocyte count, microhaematocrit, mean erythrocyte volume and mean erythrocyte haemoglobin concentration. The only effect was an increase in erythrocyte count. The value of changes in haematological parameters as indicators of pollutioninduced anemia in the field is discussed. No changes in gill ultrastructure were noted although electron micrographs of liver tissue showed lesions in hepatocytes. The diagnostic value of pollution-induced pathological changes on cell ultrastructure are discussed. Recommendations are made with regard to future large scale application of pesticides on or near large water bodies
55

Sampling Techniques for Research and Management of Cichlid Species in Lentic Systems

Bies, Jason Matthew 03 May 2019 (has links)
Introduced cichlid species are increasingly more common in tropical freshwater systems and expanding in range, often with negative consequences to receiving systems. To better understand, monitor, and manage these populations, improved cichlid sampling protocols are required. The goal of this study was to (1) evaluate diel electrofishing and gill netting sampling catch efficiency, and (2) compare two non-lethal methods for extracting stomach contents from Butterfly Peacock Bass Cichla ocellaris. This study suggests that electrofishing, particularly at night, may be a more appropriate gear for sampling cichlid species in the littoral zone of reservoirs, as gill nets were more time intensive, had more variable catch rates, and exhibited considerable selectivity. Pulsed gastric lavage was more effective than acrylic stomach tubes for extracting stomach contents from Butterfly Peacock Bass and was less injurious, with bruising of the stomach wall the most common injury being observed.
56

The effect of population density on the rate of growth of the cichlid fish, Tilapia mossambica : an experimental tank study

Schneider, Laurence H. January 1978 (has links)
No description available.
57

Níveis de proteína e energia digestíveis para tilápia-do-nilo criada em tanques-rede na fase de terminação

Koch, João Fernando Albers [UNESP] 31 July 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-07-31Bitstream added on 2014-06-13T20:24:28Z : No. of bitstreams: 1 koch_jfa_dr_botfmvz.pdf: 1044806 bytes, checksum: 6c658ab3747f48e3c863103461d1768f (MD5) / A exigência de proteína e energia digestíveis não foram determinados para tilápia-do-Nilo em sistema intensivo (tanques-rede). Este estudo avaliou os parâmetros hematológicos antes e após estresse por transporte, composição da carcaça e filé e desempenho de tilápia-do-Nilo alimentadas com níveis de proteína digestível (PD) e energia digestível (ED). Tilápias-do-Nilo (450,96 ± 9,12g) foram distribuídas em 50 tanques-rede (1m3), na densidade de 100 peixes tanque-1 e alimentadas com dietas contendo 20,0; 23,0; 26,0; 29,0 ou 32,0% de PD, 3.000 ou 3.300 kcal de ED kg-1 em delineamento em blocos casualizados (n=5) e arranjo fatorial 5x2. Após 60 dias os peixes foram pesados e as dietas quantificadas para determinar o desempenho produtivo [biomassa final (BF), ganho de biomassa (GB), conversão alimentar aparente (CAA), peso final médio (PFM), sobrevivência (SOB), taxa de eficiência protéica (TEP), rendimentos de filé (RF) e carcaça (RC) e, os índices hepatosomático (IHS) e de gordura visceral (IGV). Os teores de umidade, proteína, extrato etéreo e matéria mineral dos filés e da carcaça foram quantificados. As análises hematológicas (eritrócitos, hemoglobina, hematócrito, volume corpuscular médio, concentração de hemoglobina corpuscular média e diferenciação de leucócitos) foram realizadas e posteriormente 40 peixes foram transferidos e submetidos à estresse por transporte (5 horas de duração), sendo os mesmos parâmetros hematológicos analisados novamente. Os níveis de PD influenciaram a BF, GB, CAA, PFM e TEP. Houve interação PD x ED para RF, IHS, além da umidade, proteína bruta e extrato etéreo da carcaça. Não houve influência da ED para as variáveis de desempenho produtivo e composição do filé e carcaça. O nível de... / Digestible protein and energy have not been determined for Nile tilapia (Oreochromis niloticus) in intensive system (cages). This study evaluates hematological parameters before and after transportation stress, fillet and carcass composition and growth of Nile tilapia fed increasing levels of digestible protein (DP) and energy (DE). Nile tilapia (450.96 ± 5.12 g) were distributed into 50 1m3 cages (100 fish tank-1) and fed diets containing 20.0; 23.0; 26.0; 29.0 or 32.0% DP, 3000 or 3300 kcal DE kg-1 in a completely randomized block design (n=5) and 5x2 factorial arrangement. After 60 days the fish were weighed and the diet was quantified to determine the growth performance [final biomass (FB), biomass gain (BG), feed conversion ratio (FCR), average final weight (AFW), survival (S), protein efficiency ratio (PER) , fillet yield (FY), carcass yield (CY), hepatosomatic index (HSI) and visceral fat index (VFI)]. Moisture, protein, lipid and mineral content of the fillets and carcass were quantified. Haematological analyses (red blood cell count, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin concentration and differential counting of leucocytes) were carried out and then 40 fish were transferred and subjected to transportation stress (4 hours), after which the haematological parameters were analysed again. FB, BG, FCR, AFW and PER were influenced by DP levels. FY and HIS, as well as moisture, crude protein and ether extract of the carcass were influenced by DP x DE interaction. There was no influence of DE on the productive performance and fillet and carcass composition. 3300 kcal DE kg-1 improved animal health. Fishes presented lymphocytopenia and neutrophilia after stress, regardless of feed consumed. Considering health and growth performance it is recommended... (Complete abstract click electronic access below)
58

Níveis de proteína e energia digestíveis para tilápia-do-nilo criada em tanques-rede na fase de terminação /

Koch, João Fernando Albers, 1982- January 2013 (has links)
Orientador: Luiz Edivaldo Pezzato / Coorientador : Margarida Maria Barros / Coorientador : Maura Seiko Tsutsui Esperancini / Banca: Wilson Massamitu Furuya / Banca: Priscila Vieira Rosa / Banca: Ricardo Oliveira Orsi / Banca: José Roberto Sartori / Resumo: A exigência de proteína e energia digestíveis não foram determinados para tilápia-do-Nilo em sistema intensivo (tanques-rede). Este estudo avaliou os parâmetros hematológicos antes e após estresse por transporte, composição da carcaça e filé e desempenho de tilápia-do-Nilo alimentadas com níveis de proteína digestível (PD) e energia digestível (ED). Tilápias-do-Nilo (450,96 ± 9,12g) foram distribuídas em 50 tanques-rede (1m3), na densidade de 100 peixes tanque-1 e alimentadas com dietas contendo 20,0; 23,0; 26,0; 29,0 ou 32,0% de PD, 3.000 ou 3.300 kcal de ED kg-1 em delineamento em blocos casualizados (n=5) e arranjo fatorial 5x2. Após 60 dias os peixes foram pesados e as dietas quantificadas para determinar o desempenho produtivo [biomassa final (BF), ganho de biomassa (GB), conversão alimentar aparente (CAA), peso final médio (PFM), sobrevivência (SOB), taxa de eficiência protéica (TEP), rendimentos de filé (RF) e carcaça (RC) e, os índices hepatosomático (IHS) e de gordura visceral (IGV). Os teores de umidade, proteína, extrato etéreo e matéria mineral dos filés e da carcaça foram quantificados. As análises hematológicas (eritrócitos, hemoglobina, hematócrito, volume corpuscular médio, concentração de hemoglobina corpuscular média e diferenciação de leucócitos) foram realizadas e posteriormente 40 peixes foram transferidos e submetidos à estresse por transporte (5 horas de duração), sendo os mesmos parâmetros hematológicos analisados novamente. Os níveis de PD influenciaram a BF, GB, CAA, PFM e TEP. Houve interação PD x ED para RF, IHS, além da umidade, proteína bruta e extrato etéreo da carcaça. Não houve influência da ED para as variáveis de desempenho produtivo e composição do filé e carcaça. O nível de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Abstract: Digestible protein and energy have not been determined for Nile tilapia (Oreochromis niloticus) in intensive system (cages). This study evaluates hematological parameters before and after transportation stress, fillet and carcass composition and growth of Nile tilapia fed increasing levels of digestible protein (DP) and energy (DE). Nile tilapia (450.96 ± 5.12 g) were distributed into 50 1m3 cages (100 fish tank-1) and fed diets containing 20.0; 23.0; 26.0; 29.0 or 32.0% DP, 3000 or 3300 kcal DE kg-1 in a completely randomized block design (n=5) and 5x2 factorial arrangement. After 60 days the fish were weighed and the diet was quantified to determine the growth performance [final biomass (FB), biomass gain (BG), feed conversion ratio (FCR), average final weight (AFW), survival (S), protein efficiency ratio (PER) , fillet yield (FY), carcass yield (CY), hepatosomatic index (HSI) and visceral fat index (VFI)]. Moisture, protein, lipid and mineral content of the fillets and carcass were quantified. Haematological analyses (red blood cell count, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin concentration and differential counting of leucocytes) were carried out and then 40 fish were transferred and subjected to transportation stress (4 hours), after which the haematological parameters were analysed again. FB, BG, FCR, AFW and PER were influenced by DP levels. FY and HIS, as well as moisture, crude protein and ether extract of the carcass were influenced by DP x DE interaction. There was no influence of DE on the productive performance and fillet and carcass composition. 3300 kcal DE kg-1 improved animal health. Fishes presented lymphocytopenia and neutrophilia after stress, regardless of feed consumed. Considering health and growth performance it is recommended... (Complete abstract click electronic access below) / Doutor
59

Produção de fitases e proteases fúngicas, aplicação em rações e valores digestíveis pela tilápia-do-nilo /

Novelli, Paula Kern, 1978. January 2015 (has links)
Orientador: Luciana Francisco Fleuri / Coorientador: Margarida Maria Barros / Banca: Pedro de Magalhães Padilha / Banca: Ruann Janser Soares de Castro / Banca: Fernanda Mani / Banca: Gabriela Alves Macedo / Resumo: Este estudo foi realizado para o rastreio da produção de fitase utilizando resíduos agroindustriais como substrato para fermentação em estado sólido (SSF) e várias cepas fúngicas. A alta produção de fitase foi observada para a maioria dos microrganismos estudados, bem como características muito diferentes actividades bioquímicas, incluindo a valores de pH específicos. As fitases mostrou um comportamento muito distinto de óptimo e estabilidade do pH, os valores ideais de temperatura e estabilidade. A. niger mostrou os maiores valores de atividade enzimática. Enzima liofilizada produzida por A. niger atingiu 8,575 U / g e rendimento de 826,096.50 U / Kg de substrato quando fermentado em farelo de trigo. Portanto, o substrato, bem como a estirpe de microorganismo pode alterar as características bioquímicas da enzima produzida. A alta atividade de fitase e características muito distintas estabelecidas, além do baixo custo de substratos, fazer estes fungos fitases alternativas potenciais para a indústria biotecnológica. / Abstract: This study was carried out for screening the phytase production using agroindustrial residues as substrate for solid state fermentation (SSF) and several fungal strains. High phytase production was observed for most of the microorganisms studied, as well as very different biochemical characteristics, including activities at specific pH values. The phytases showed very distinct behavior of optimum and stability pH, optimal values of temperature and stability. A. niger showed the higher values of enzyme activity. Lyophilized enzyme produced by A. niger reached 8,575 U/g and yield of 826,096.50 U/Kg of substrate when fermented in wheat bran. Therefore, the substrate as well as the microorganism strain can affect the biochemical character of the enzyme produced. The high phytase activity and very distinct characteristics established, plus the low cost of substrates, make these fungal phytases potential alternatives for biotechnological industry. / Doutor
60

Plasma sanguíneo desidratado na alimentação da Tilápia-do- Nilo /

Araujo, Eric Portilho, 1989. January 2015 (has links)
Orientador: Margarida Maria Barros / Banca: Luiz Edivaldo Pezzato / Banca: Hamilton Hisano / Resumo: Este estudo avaliou a inclusão de plasma sanguíneo desidratado (PD) na dieta da tilápia-do-Nilo por meio de uma pesquisa dividida em duas fases: na Fase I, com duração de 60 dias, avaliou-se o desempenho produtivo e parâmetros histológicos dos peixes alimentados com cinco dietas: PD0 (controle); PD 1,66; PD 3,32; PD 4,97; PD 6,63% de inclusão de PD. Para isto distribuiu-se 440 peixes em 40 aquários de 250 L dotados de filtro físico e biológico com controle de temperatura (26 ±1°C). Na Fase II avaliou-se os parâmetros hematológicos de juvenis de tilápia-do- Nilo, antes e após o estresse por baixa temperatura (16°C) durante sete dias, utilizandose de 60 peixes distribuídos aleatoriamente em 30 aquários de 40 L, dotados de biofiltros e aeração individuais. A inclusão de PD determinou maior ganho de peso e peso final e melhora da integridade intestinal. Manutenção e/ou estímulo à eritropoiese foi observado com a inclusão de PD inferindo melhor higidez e resistência orgânica aos peixes expostos ao estresse por baixa temperatura. Aumento na produção de neutrófilos e manutenção de monócitos demonstrou o efeito estimulatório do PD sobre o sistema imune inato. Os dados foram submetidos à análise de variância (P<0,05), complementado pelo teste de comparações múltiplas de Tukey. Foram realizadas análises de regressão nos casos em que o modelo foi significativo (R2 >0,70). Para dados fora da curva de normalidade, aplicou-se o teste não paramétrico de Kruskal- Wallis (P<0,05), complementados com o teste de comparações de Mann-Whitney. A inclusão de PD à dieta de Oreochromis niloticus melhora o desempenho produtivo, a saúde intestinal, perfil hematológico e resistência orgânica ao estresse por baixa temperatura. Com base nos resultados de desempenho e histologia, recomenda-se o nível de inclusão de 4,97% à dieta, pois traz mais benefícios quando comparado ao ... / Abstract: This study evaluated the inclusion of dehydrated blood plasma (PD) on Nile tilapia diet by a research divided in two stages: 1° Stage, after 60 days, was measured the productive performance and histological parameters of fish, whose received five diets: PD0 (control); PD 1,66; PD 3,32; PD 4,97; PD 6,63% of dehydrated blood plasma inclusion. 440 fish was randomized into 40 aquariums (250 L) with physic-biological filter and automatic system water control (26 ±1°C) on the 1°st. On the second stage, was evaluated hematological parameters of Nile tilapia juveniles, before and after the cold stress (16°C). During seven days, 60 fish were allocated in 30 aquariums (40 L), with individual aeration and filters, provided by a division in each, that assure individuals spaces. PD inclusion results presented greater weight gain, final weight and improves the intestinal integrity. Maintenance and/or stimulation of erythropoiesis was observed with the addition of PD, inferring better health and fish organic resistance exposed to stress by low temperature. Increased production of neutrophils and monocytes maintenance, demonstrated the stimulatory effect of PD on the innate immune system . The data was submitted to the analysis technique variance (P<0.05), complemented by the multiple comparison Tukey test. Regression analyzes were performed when the model was significant (R2>0.70). For outresults of the normal curve, was applied the nonparametric Kruskal-Wallis analysis (P<0,05), complemented by Mann-Whitney test comparisons. The inclusion of PD for Oreochromis niloticus on diet, improves growth performance, gut health, blood profile and organic resistance to stress by low temperature. Based on the results of growth performance and histology, is recommended the PD inclusion of 4.97 % on the diet, because it brings more benefits when compared to PD treatment without inclusion / Mestre

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