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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.
1

The Economics of Partial Artemia Replacement Using Two Commercially Available Feeds in the Diets of Litopenaeus vannamei from Z3/M1 – PL10

Giguere, Monique A 01 December 2011 (has links)
The purpose of this study was twofold: 1) to identify commercially available feeds that could serve as suitable replacements for newly hatched Artemia in the diets of L. vannamei from Z3/M1 to PL10 without significantly affecting survival, final length and weight, and quality of the larvae and 2) to identify an ideal substitution rate between live Artemia and a replacement feed that maximizes feed and labor costs savings, survival, and PL quality. In Experiment 1, two commercially available Artemia replacement feeds, Zeigler EZ Artemia and Bernaqua Vitellus, were administered according to manufacturer’s guidelines in order to identify which feed served as a more suitable replacement diet. In Experiment 2, the more successful feed from Experiment 1 was administered in three different co-feeding strategies, in which the inert feed replaced a certain percentage of live Artemia. Mean percent survival was not significantly different between the Control, EZ Artemia, and Vitellus treatment groups in Experiment 1 (P<0.05). Both the EZ Artemia and Vitellus treatments yielded significantly different final mean lengths (mm) and weights (mg) from the Control group. The Vitellus feed results for all performance factors (mean percent survival, final length (mm), final weight (mg), and percent stress test mortality) were not significantly different than those of the EZ Artemia treatment, despite receiving no Artemia during the culture period, while the EZ Artemia treatment received 75% Artemia from PL5-PL10. For these reasons, the Vitellus feed was selected as the more successful feed in Experiment 1. In Experiment 2, there was no significant difference between the four treatment groups (Control, V50, V100/50, and V100/75) for mean percent survival and percent stress test mortality (P<0.05). The V100/50 and V100/75 treatments’ mean final lengths (mm) and weights (mg) were significantly different than those of the Control treatment. There were no significant differences between the V50, V100/50, and V100/75 treatments for any of the observed performance factors. These results indicate that the maximum substitution rate of Vitellus for Artemia in this experiment (the V100/75 treatment) was successful in replacing 84.33% of newly hatched Artemia in the larval culture of L. vannamei from Z3/M1-PL10 without resulting in significantly different survival and stress test mortalities compared to the Control group. Feeding schedules such as V100/75 treatment help streamline production efforts in commercial operations and result in increased production cost savings when compared to other replacement feeding schedules that begin in the early mysis stages. The V100/75 feeding schedule influences variable feed and labor costs the greatest because farmers are able to delay the culturing of Artemia an additional 7 days (until PL5) from what is typically performed in larviculture facilities.
2

Digestibilidade aparente de ingredientes por alevinos de tilápia do nilo (Oreochromis Niloticus) /

Nakagome , Fernando Kojima, 1980- January 2009 (has links)
Resumo: A formulação de ração específica para as fases iniciais de desenvolvimento dos peixes só pode ser obtida pelo conhecimento do valor nutritivo dos alimentos que a compõem e estes dependem de seu conteúdo em nutrientes e da capacidade do animal em ingerí-los e absorvê-los. Os coeficientes de digestibilidade aparente (CDA) da matéria seca, proteína bruta e energia bruta de alguns ingredientes energéticos foram avaliados para alevinos de tilápia do Nilo com pesos iniciais de 0,60; 1,14 e 2,37 g. Os ingredientes estudados foram: milho, quirera de arroz, sorgo e farelo de trigo. O óxido de crômio-III foi utilizado como marcador externo e a coleta de fezes foi feita pelo método de Guelph modificado. Os melhores resultados de digestibilidade aparente foram obtidos pelo milho e quirera de arroz para os três tamanhos de alevinos, sendo que o sorgo se igualou a estes dois ingredientes quando ofertado aos alevinos de tamanho intermediário. O farelo de trigo apresentou os piores CDA para a matéria seca e energia bruta. Conclui-se o milho e a quirera de arroz são excelentes ingredientes energéticos para rações de alevinos de tilápia do Nilo. / Abstract: Formulation of a specific diet for fish in initial development stage can only be made after knowing the nutritional values of feedstuffs which depends on nutrient contents and the fish capacity to digest and absorb it. The apparent digestibility coefficients (ADC) of dry matter, crude protein and crude energy of energetic ingredients were evaluated to Nile tilapia post larvae with initial body weights of 0.60; 1.14 e 2.37 g. The evaluated ingredients were: corn, rice, sorghum and wheat bran. Chromic oxide was the external digestibility marker and feces collection followed modified Guelph method. Corn and rice showed the best ADCs for the three fish size. However, sorghum had equivalent ADCs when intermediate fish size were fed. Wheat bran showed the worse ADCs for dry matter and crude energy. Nile tilapia post larvae are capable of using energy and protein from corn and rice, thus they can be considered excellent energetic feed ingredients. / Orientador: Antonio Celso Pezzato / Coorientador: Margarida Maria Barros / Banca: Dirlei Antonio Berto / Banca: Wilson Massamitu Furuya / Mestre
3

Digestibilidade aparente de ingredientes por alevinos de tilápia do nilo (Oreochromis Niloticus)

Nakagome , Fernando Kojima [UNESP] 30 March 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-30Bitstream added on 2014-06-13T20:16:55Z : No. of bitstreams: 1 nakagome_fk_me_botfmvz.pdf: 413782 bytes, checksum: 3ab9336fae68bb9f65f99a7f3508f624 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / A formulação de ração específica para as fases iniciais de desenvolvimento dos peixes só pode ser obtida pelo conhecimento do valor nutritivo dos alimentos que a compõem e estes dependem de seu conteúdo em nutrientes e da capacidade do animal em ingerí-los e absorvê-los. Os coeficientes de digestibilidade aparente (CDA) da matéria seca, proteína bruta e energia bruta de alguns ingredientes energéticos foram avaliados para alevinos de tilápia do Nilo com pesos iniciais de 0,60; 1,14 e 2,37 g. Os ingredientes estudados foram: milho, quirera de arroz, sorgo e farelo de trigo. O óxido de crômio-III foi utilizado como marcador externo e a coleta de fezes foi feita pelo método de Guelph modificado. Os melhores resultados de digestibilidade aparente foram obtidos pelo milho e quirera de arroz para os três tamanhos de alevinos, sendo que o sorgo se igualou a estes dois ingredientes quando ofertado aos alevinos de tamanho intermediário. O farelo de trigo apresentou os piores CDA para a matéria seca e energia bruta. Conclui-se o milho e a quirera de arroz são excelentes ingredientes energéticos para rações de alevinos de tilápia do Nilo. / Formulation of a specific diet for fish in initial development stage can only be made after knowing the nutritional values of feedstuffs which depends on nutrient contents and the fish capacity to digest and absorb it. The apparent digestibility coefficients (ADC) of dry matter, crude protein and crude energy of energetic ingredients were evaluated to Nile tilapia post larvae with initial body weights of 0.60; 1.14 e 2.37 g. The evaluated ingredients were: corn, rice, sorghum and wheat bran. Chromic oxide was the external digestibility marker and feces collection followed modified Guelph method. Corn and rice showed the best ADCs for the three fish size. However, sorghum had equivalent ADCs when intermediate fish size were fed. Wheat bran showed the worse ADCs for dry matter and crude energy. Nile tilapia post larvae are capable of using energy and protein from corn and rice, thus they can be considered excellent energetic feed ingredients.
4

Índices zootécnicos, reprodutivos e parâmetros bioquímicos de fêmeas de jundiá Rhamdia quelen alimentadas com diferentes níveis de proteína e lipídio / Zootechnics, reproductive indexes and biochemical s parameters of catfishes Rhamdia quelen female fed with different lipids and proteins levels

Coldebella, Ivanir José 16 December 2010 (has links)
In this study were evaluated the zootechnics, reproductive aspects and biochemical s parameters aspects of female catfishes fed with three lipids and proteins levels on diets. Two experiments were conducted, the first being held between July 15th and October 15th, 2008, followed by a period of 14 days to create the post-larvae. We used 66 females with 14 months old (weight between 465,1 and 690,3g). 18 females were slaughtered for evaluation of biochemical s and histological parameters and 54 were distributed on six 1m³-net cage, fed at 9 a.m. and 4 p.m., at ease, during 90 days, with pelletized rations containing 28, 34 and 40% of PB and 14% of total lipids. Twelve females were induced to spawn to reproductive evaluation (fertilization rate, egg s number, eggs and larvae s biometrics and prost-larvae s growth). At experiment I, the results indicated that the increase of protein s level at diet didn t influence the zootechnics, reproductive and biochemical s parameters, however the 28% of PB level was superior for the post-larvae s growth on the variables weight, length and weight versus survival in 14 days. The second experiment was performed between July 15th and October 15th, 2009, and we used the best diet of first experiment (28% of PB and 14% of lipids), settling the 8, 14 and 20% of lipids and 28% of PB levels. In this experiment was selected 93 females with 14 months old and weighting between 596,28 and 640,4g and 66 of which was distributed on six net cages and 27 was slaughtered for evaluation of biochemical s and histological parameters and the gonad's lipid profile. For both experiments were followed the same procedure, just adding, at the second, the evaluation of ovaries and muscles lipids profile. The results of experiment II also didn t show difference to the zootechnics and biochemical s parameters, but there was a linear increase in visceral fat index with the increased level of lipid in the diets. The fatty acids profile didn t differ between the treatments, but there was variation in concentration. The egg s diameter and area were significantly smaller to the 20% of lipids level, damaging the post-larvae s growth, survival and weight versus survival. The best reproductive s answers to catfishe s females were obtained with diets containing 28% of PB and between 8 and 14% of total lipids. / Neste estudo avaliaram-se os aspectos zootécnicos, reprodutivos e parâmetros bioquímicos de fêmeas de jundiá alimentadas com três níveis protéicos e lipídicos nas dietas. Foram conduzidos dois experimentos, sendo o primeiro realizado entre 15 de julho e 15 de outubro de 2008, seguindo-se um período de mais 14 dias para a criação das pós-larvas. Utilizou-se 66 fêmeas com 14 meses de idade (peso entre 465,1 e 690,3 g). Foram abatidas 18 fêmeas para avaliação dos parâmetros bioquímicos e histológicos e 54 foram distribuídas em seis tanques-rede de 1m3, alimentadas às 9 e 16 h, a vontade, durante 90 dias, com rações peletizadas contendo 28, 34 e 40 % de PB e 14 % de lipídio total. Doze fêmeas foram induzidas à desova para avaliação da reprodução (taxa de fecundação, número de ovos, biometria dos ovos e larvas e crescimento das pós-larvas). No experimento I, os resultados indicaram que o aumento do nível de proteína nas dietas não influenciou os parâmetros zootécnicos, bioquímicos e reprodutivos, no entanto o nível de 28 % de PB mostrou-se superior para o crescimento das pós-larvas nas variáveis peso médio, comprimento total e peso versus sobrevivência aos 14 dias (P>0,05). O segundo experimento foi realizado no período entre 15 de julho e 15 de outubro de 2009 e utilizou-se a melhor dieta do experimento I (28 % PB e 14 % de lipídio), fixando-se os níveis em 8, 14 e 20 % de lipídio e 28 % de PB. Neste experimento foram selecionadas 93 fêmeas com 14 meses de idade e peso entre 596,28 e 640,4 g e 66 foram distribuídas em seis tanques-rede e 27 foram abatidas para avaliação dos parâmetros bioquímicos, histológicos e perfil lipídico das gônadas. Para os dois experimentos seguiram-se os mesmos procedimentos, apenas acrescido, no segundo, da avaliação do perfil lipídico dos ovários e músculos. Os resultados do experimento II igualmente não se mostraram diferentes para os parâmetros zootécnicos e bioquímicos, porém houve aumento linear do índice de gordura visceral com o aumento do nível de lipídio nas dietas. O perfil de ácidos graxos não diferiu entre os tratamentos. O diâmetro e a área do ovo foram significativamente menores para o nível de 20 % de lipídio, prejudicando o crescimento, sobrevivência e peso versus sobrevivência das pós-larvas (P>0,05). As melhores respostas reprodutivas para fêmeas de jundiá foram obtidas com as dietas contendo 28 % de PB e entre 8 e 14 % de lipídio total.
5

Sex reversal of Nile tilapia, Oreochromis niloticus (vr. Chitralada) at different salinities in the presence of microalgae Spirulina platensis (Cyanophyta) / ReversÃo sexual da tilÃpia do Nilo, Oreochromis niloticus (vr. Chitralada), em diferentes salinidades na presenÃa da microalgas Spirulina platensis (Cyanophyta)

Ricardo Lafaiete Moreira 16 June 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A larva da tilÃpia do Nilo, Oreochromis niloticus, durante os primeiros dias de vida, supre suas necessidades nutricionais com a reserva vitelÃnica, pois nem a cavidade bucal encontra-se aberta nem o trato intestinal completamente formado. ApÃs o consumo do vitelo, o peixe jà à uma pÃs-larva e sua alimentaÃÃo passa a ser exÃgena e à composta, principalmente, por microalgas e zooplÃncton. O objetivo desse trabalho foi avaliar a influÃncia da cianobactÃria Spirulina platensis, no desempenho de pÃs-larvas (plâs) da tilÃpia do Nilo, submetidas a diferentes salinidades durante o perÃodo de reversÃo sexual. Na primeira fase da pesquisa, alÃm da S. platensis, tambÃm foi ofertado ,em todos os tratamentos, raÃÃo microparticulada (50% PB) contendo o hormÃnio masculinizante 17-&#945;-metiltestosterona, com o intuito de realizar a reversÃo sexual dos peixes.O delineamento foi inteiramente casualizado e dividido em trÃs tratamentos com trÃs repetiÃÃes cada. Os peixes foram cultivados nas salinidades 0 ,15 e 25 ,apresentaram pesos e comprimentos mÃdios finais 1,547  0,145 g e 4,753  0,209 cm; 1,618  0,154 g e 4,957  0,131 cm e 1,580  0,090 g e 4,844  0,025 cm, respectivamente, apÃs 28 dias de cultivo, onde nÃo foi apresentada diferenÃa estatÃstica (&#945; = 0,05). ApÃs esse perÃodo os peixes da salinidade 15 e 25 foram aclimatados novamente a salinidade 0 e distribuÃdos em caixas de 1000 L na densidade de 0,05 peixes L -1 e cultivados por 35 dias, apÃs esse perÃodo foi avaliado a taxa de reversÃo sexual, o crescimento em peso e comprimento e a taxa de sobrevivÃncia dos animais, nessa fase foi oferecido apenas raÃÃo 35% PB sem hormÃnio. Ao final dessa fase, os peixes apresentaram pesos e comprimentos mÃdios de 11,923 g e 8,888 cm; 12,033 g e 9,716 cm e 12,604 g e 10,001 cm para os peixes oriundos das salinidades de 0 ,15 e 25 , respectivamente. ApÃs a anÃlise gonadal, os Ãndices de reversÃo sexual nÃo apresentaram diferenÃas significativas entre os tratamentos, com mÃdia de 97,3% de indivÃduos machos. Com a realizaÃÃo desse trabalho pudemos concluir que a salinidade da Ãgua nÃo interferiu no crescimento em peso e comprimento, Ãndice de reversÃo sexual e sobrevivÃncia da tilÃpia do Nilo (O. niloticus), durante a reversÃo sexual na presenÃa da microalga Spirulina platensis / The larva of the Nile tilapia, Oreochromis niloticus, during the first days of life meets its meets their nutrition needs with the vitelline reserve, because neither the buccal cavity is open nor the intestinal tract is completely formed. After the consumption of the vitellus, the fish is already a post-larva and it s feeding becomes exogenous and mainly composed of microalgae and zooplankton. The objective of this work was to evaluate the influence of the cyanobacterium Spirulina platensis, in the performance of post-larvae (pl's) of the Nile tilapia submitted to different salinity levels during the period of sex reversal. In the first phase of the research, besides S. platensis , we also supplied, in all of the treatments, a microparticulate feed (50% of crude protein) containing the masculinizing hormone 17-&#945;-metiltestost erone, with the intention of conducting the sex reversal of the fish. The experimental design was completely randomized and divided into three treatments with three replications per treatment. The fish were farmed in the salinity levels of 0, 15 and 25, and presented weights and final medium lengths of 1,547  0,145 g and 4,753  0,209 cm; 1,618  0,154 g and 4,957  0,131 cm and 1,580  0,090 g and 4,844  0,0 25 cm, respectively, after 28 days of farming, in which there was no statistical difference (&#945; = 0,05). After that period, the fish of the salinity levels of 15 and 25 were acclimatized to 0 (zero) salinity level again and distributed into boxes of 1000 L in the density of 0,05 fish L-1 and farmed for 35 days. After that period, the rate of sex reversal, the growth in weight and length and the survival rate of the animals were evaluated. In that phase, we supplied only a feed of 35% of crude protein without hormone. At the end of that phase, the fish presented average weights and lengths of 11.923 g and 8.888 cm; 12.033 g and 9.716 cm and 12.604 g and 10.001 cm for the fish coming from the salinity levels of 0, 15 and 25, respectively. After the gonadal analysis, the rates of ix sex reversal did not present significant differences among the treatments, with an average of 97.3% of male individuals. The conduction of this work enabled us to conclude that the water salinity did not interfere with the growth in weight and length, the rate of sex reversal and the survival of the Nile tilapia (O. niloticus), during the sex reversal in the presence of the microseaweed Spirulina platensis.
6

Reversão sexual da tilápia do Nilo, Oreochromis niloticus (vr. Chitralada), em diferentes salinidades na presença da microalgas Spirulina platensis (Cyanophyta) / Sex reversal of Nile tilapia, Oreochromis niloticus (vr. Chitralada) at different salinities in the presence of microalgae Spirulina platensis (Cyanophyta)

Moreira, Ricardo Lafaiete January 2008 (has links)
MOREIRA, Ricardo Lafaiete. Reversão sexual da tilápia do Nilo, Oreochromis niloticus (vr. Chitralada), em diferentes salinidades na presença da microalgas Spirulina platensis (Cyanophyta). 2008. 47 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 2016-07-21T14:22:36Z No. of bitstreams: 1 2008_dis_rlmoreira.pdf: 413193 bytes, checksum: a96f56cb63d867a172085001d6980a78 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-21T14:24:36Z (GMT) No. of bitstreams: 1 2008_dis_rlmoreira.pdf: 413193 bytes, checksum: a96f56cb63d867a172085001d6980a78 (MD5) / Made available in DSpace on 2016-07-21T14:24:36Z (GMT). No. of bitstreams: 1 2008_dis_rlmoreira.pdf: 413193 bytes, checksum: a96f56cb63d867a172085001d6980a78 (MD5) Previous issue date: 2008 / The larva of the Nile tilapia, Oreochromis niloticus, during the first days of life meets its meets their nutrition needs with the vitelline reserve, because neither the buccal cavity is open nor the intestinal tract is completely formed. After the consumption of the vitellus, the fish is already a post-larva and it s feeding becomes exogenous and mainly composed of microalgae and zooplankton. The objective of this work was to evaluate the influence of the cyanobacterium Spirulina platensis, in the performance of post-larvae (pl's) of the Nile tilapia submitted to different salinity levels during the period of sex reversal. In the first phase of the research, besides S. platensis , we also supplied, in all of the treatments, a microparticulate feed (50% of crude protein) containing the masculinizing hormone 17-α-metiltestost erone, with the intention of conducting the sex reversal of the fish. The experimental design was completely randomized and divided into three treatments with three replications per treatment. The fish were farmed in the salinity levels of 0, 15 and 25, and presented weights and final medium lengths of 1,547 ± 0,145 g and 4,753 ± 0,209 cm; 1,618 ± 0,154 g and 4,957 ± 0,131 cm and 1,580 ± 0,090 g and 4,844 ± 0,0 25 cm, respectively, after 28 days of farming, in which there was no statistical difference (α = 0,05). After that period, the fish of the salinity levels of 15 and 25 were acclimatized to 0 (zero) salinity level again and distributed into boxes of 1000 L in the density of 0,05 fish L-1 and farmed for 35 days. After that period, the rate of sex reversal, the growth in weight and length and the survival rate of the animals were evaluated. In that phase, we supplied only a feed of 35% of crude protein without hormone. At the end of that phase, the fish presented average weights and lengths of 11.923 g and 8.888 cm; 12.033 g and 9.716 cm and 12.604 g and 10.001 cm for the fish coming from the salinity levels of 0, 15 and 25, respectively. After the gonadal analysis, the rates of ix sex reversal did not present significant differences among the treatments, with an average of 97.3% of male individuals. The conduction of this work enabled us to conclude that the water salinity did not interfere with the growth in weight and length, the rate of sex reversal and the survival of the Nile tilapia (O. niloticus), during the sex reversal in the presence of the microseaweed Spirulina platensis. / A larva da tilápia do Nilo, Oreochromis niloticus, durante os primeiros dias de vida, supre suas necessidades nutricionais com a reserva vitelínica, pois nem a cavidade bucal encontra-se aberta nem o trato intestinal completamente formado. Após o consumo do vitelo, o peixe já é uma pós-larva e sua alimentação passa a ser exógena e é composta, principalmente, por microalgas e zooplâncton. O objetivo desse trabalho foi avaliar a influência da cianobactéria Spirulina platensis, no desempenho de pós-larvas (pl’s) da tilápia do Nilo, submetidas a diferentes salinidades durante o período de reversão sexual. Na primeira fase da pesquisa, além da S. platensis, também foi ofertado ,em todos os tratamentos, ração microparticulada (50% PB) contendo o hormônio masculinizante 17-α-metiltestosterona, com o intuito de realizar a reversão sexual dos peixes.O delineamento foi inteiramente casualizado e dividido em três tratamentos com três repetições cada. Os peixes foram cultivados nas salinidades 0 ,15 e 25 ,apresentaram pesos e comprimentos médios finais 1,547 ± 0,145 g e 4,753 ± 0,209 cm; 1,618 ± 0,154 g e 4,957 ± 0,131 cm e 1,580 ± 0,090 g e 4,844 ± 0,025 cm, respectivamente, após 28 dias de cultivo, onde não foi apresentada diferença estatística (α = 0,05). Após esse período os peixes da salinidade 15 e 25 foram aclimatados novamente a salinidade 0 e distribuídos em caixas de 1000 L na densidade de 0,05 peixes L -1 e cultivados por 35 dias, após esse período foi avaliado a taxa de reversão sexual, o crescimento em peso e comprimento e a taxa de sobrevivência dos animais, nessa fase foi oferecido apenas ração 35% PB sem hormônio. Ao final dessa fase, os peixes apresentaram pesos e comprimentos médios de 11,923 g e 8,888 cm; 12,033 g e 9,716 cm e 12,604 g e 10,001 cm para os peixes oriundos das salinidades de 0 ,15 e 25 , respectivamente. Após a análise gonadal, os índices de reversão sexual não apresentaram diferenças significativas entre os tratamentos, com média de 97,3% de indivíduos machos. Com a realização desse trabalho pudemos concluir que a salinidade da água não interferiu no crescimento em peso e comprimento, índice de reversão sexual e sobrevivência da tilápia do Nilo (O. niloticus), durante a reversão sexual na presença da microalga Spirulina platensis

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