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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.
351

The lethal and sublethal effects of aldicarb on the estuarine grass shrimp, Palaemonetes pugio

Dvorak-Grantz, Andrea Lynn 18 November 2008 (has links)
Estuaries, an important facet of coastal regions, are highly productive natural systems, frequently acting as drainage basins for various pollutants such as agricultural runoff. The estuarine grass shrimp, Palaemonetes pugio, has been shown to be a sensitive indicator of pesticide exposure. In this study, emphasis was placed on the quantification of the lethal and sublethal effects of aldicarb on three different life stages of P. pugio. Acute 96-h toxicity tests were conducted with newly hatched larvae, 22-d old larvae and adult grass shrimp to determine lethal toxicant ranges. LC₅₀ values were 85.0 ug/L for newly hatched larvae, 70.7 ug/L for 22-d old larvae and 125.4 ug/L for adults. The impact of aldicarb on specific neurological functions in the grass shrimp was examined using an acetylcholinesterase assay. Acetylcholinesterase (AChE) activity was reduced in the larvae after exposure to acute concentrations of aldicarb. Mean whole-body AChE activity for the newly hatched and 22-d larvae was significantly lower from the controls (P=0.009). Conversely, mean whole body AChE activity in the adult shrimp was not significantly different from the controls at any concentration (P=0.401), although there was a trend towards reduced activity at 50 and 100 ug/L exposures. A behavioral study was conducted to examine the ability of adult grass shrimp to detect and avoid aldicarb-treated seawater. Behavioral responses were measured in a modified steep gradient chamber. A partition divided the chamber, creating three distinct areas: 1) seawater 2) aldicarb-treated seawater and 3) mixing. There were significant differences between the control and exposed adult shrimp in the amount of time spent in the mixing area (P<0.05). Aldicarb exposed shrimp spent, on the average, 20% more time in the mixing area than the controls. Additionally, exposed shrimp spent significantly more time facing downstream, away from the toxicant source (P<0.05). Exposed shrimp displayed increasing hyperactivity and attempted to jump out of the chamber. / Master of Science
352

Assessment of Current Guidelines for Culinary Preparation Methods of Fish and Shellfish

Kostal, Jeri Elizabeth 17 December 2012 (has links)
Consumers regularly decide to consume fish and shellfish raw or undercooked, which can cause foodborne illness due to product contamination or unsafe handling by the consumer.  In order to be considered safe for consumption, intact fish and shellfish should be prepared to an internal temperature of 63"C, according to the 2009 FDA Food Code, with Salmonella spp. as the target organism.  Focus groups (5 groups, 32 participants) were conducted to determine consumer beliefs and concerns regarding fish and shellfish safety and preparation.  Transcripts of focus groups where coded for themes, which were then grouped into categories.  Nine categories emerged including:  experience, trust, confidence, quality of product, motivation, concerns, cooking procedures, cooking instructions, and knowledge.  Emerging themes were used to help develop educational materials to increase consumer ability to properly prepare fish and shellfish.  In a separate experiment, participants (n=6) cooked salmon (baked, broiled), tilapia (baked, broiled), and shrimp (broiled, boiled) according to cookbook-based directions.    Internal temperatures of products were recorded, with 33.3% of products cooked to a temperature less than 63"C.  A group training session was held, during which participants received additional visual and non-oral cues to determine when products were prepared to 63"C and safe food handling practices.  After training, participants prepared the same products.  Participants demonstrated improved food safety behaviors and were more successful at cooking products to temperatures "63"C (94.4% of products).  Improved cooking instruction and educational materials may reduce the risk of foodborne illness from undercooked fish and shellfish. / Master of Science in Life Sciences
353

A Survey of the Agronomic and End Use Characteristics of Low Phytic Acid Soybeans

Averitt, Benjamin James 10 June 2016 (has links)
Phytic acid (PA) accounts for up to 75% of the P in soybean (Glycine max L. Merr.) seeds, but it is indigestible by mono- and agastric animals resulting in economic and environmental detriment. Soybean lines with genetically reduced PA contents have been developed using three distinct mutant alleles at the MIPS1, LPA1, and LPA2 genes resulting in up to a 75% reduction in PA. Low PA (LPA) soymeal-based feeds have been tested on several agricultural species and shown to reduce the P in the animal effluent, but they have not been tested on any aquacultural species. However, LPA soybean lines often exhibit low field emergence making them commercially inviable. The cause of this phenomenon is widely debated with possibilities ranging from increased disease pressure to decreased seedling vigor. The objectives of this research were to 1) enhance field emergence of LPA soybean varieties through pre-planting seed treatments, 2) study the impact of the LPA mutant alleles on agronomic, quality, and seed composition traits, and 3) design a low-error method for studying the effect of LPA soymeal-based feeds on aquatic animals using Pacific White Shrimp (Litoenaeus vannamei). These results describe a variety of agronomic and genetic strategies with which the low field emergence of LPA soybeans can be addressed, reveal a heretofore not reported interaction between the mips1 and lpa2 alleles to further increase the digestibility of soymeal, and a possible method for studying LPA soymeal based feed on aquacultural animals. / Master of Science
354

Use of Direct-Fed Microbes To Enhance Shrimp Resistance to a Vibrio Parahaemolyticus Strain Causing Early Mortality Syndrome

Taylor, Zachary William 20 June 2019 (has links)
Early Mortality Syndrome (EMS) is a widespread bacterial infection of shrimp, attributed to pathogenic Vibrio parahaemolyticus strains (VP-EMS). This disease threatens aquaculture production and global food security. A valuable and alternative approach to using antibiotics for pathogen control, is the practice of incorporating direct-fed microbes (DFM) or probiotics. In order to evaluate the hypothesis that probiotics (specific strains of Bacillus subtilis spores) are able to provide shrimp, Litopenaeus vannamei, protection to the EMS disease, a pathogen growth model, disease challenge model, and probiotic feed coating methodologies were developed and refined, allowing independent shrimp probiotic trials to be piloted. A single probiotic strain of Bacillus subtilis: O14VRQ and a blend of Bacillus subtilis strains: Plus10, were evaluated as feed additives or as water additions, for their efficacy. Accordingly, two independent trials were conducted in which shrimp were fed daily with a probiotic-coated feed for seven days, before a challenge with VP-EMS. Each trial consisted of a negative control (no VP-EMS exposure, no probiotic) and positive control (VP-EMS exposure, no probiotic), with five additional probiotic treatment groups, which were fed and exposed to VP-EMS in the same manner as the positive control. Shrimp were observed for clinical signs of disease after the initial exposure and were continuously exposed every 24 hours until 50% of the population remained in the positive control treatment. Both probiotics studied were shown to significantly (p < 0.05) improve shrimp survival. Overall the data presented in this work demonstrates that probiotic prophylaxis is reliant upon probiotic dose, regardless of application. / Master of Science in Life Sciences / Aquaculture is one of the fastest growing agricultural sectors in the world allowing it to greatly contribute to global food security. Seafood products are known for their excellent health benefits, providing good sources of protein, fatty acids, and vitamins. However, the animals raised in this industry, like in many facets of animal agriculture, are susceptible to disease. Diseases can be costly to treat and if no treatment exists, can be detrimental to farms, especially to highly valued species such as shrimp. Traditionally, many diseases have been treated with antibiotics, however this can promote the growth of antibiotic resistant bacteria, which is a public health concern especially when involving animals fit for human consumption. An alternative to this approach is administering probiotics or beneficial bacteria to these animals. When incorporated with feed or applied to water, these beneficial bacteria can prevent diseases and help promote the growth of healthy animals. Two novel probiotics were fed to shrimp, before exposing them to the bacteria, Vibrio parahaemolyticus, which causes Early Mortality Syndrome, and is responsible for annual shrimp losses of more than $1 billion USD. Signs of this disease and survival were observed to assess if this probiotic could provide protection against this bacterium. Results from these studies show that these probiotics were capable of offering protection to shrimp when they were fed or introduced into tank water in high concentrations. Such probiotic applications could have beneficial effects on intensive shrimp aquaculture and help prevent this disease.
355

Petrologia e geocronologia do stock granodiorítico Lagoa do Roçado, domínio Mucururé, faixa sergipana-SE

Silva, Cleverton Correia 27 February 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Lagoa do Roçado Granodioritic Stock is a body with approximately 12 km2, elongated intrusive in metasediments Macururé Domain, located in central region of Sergipana Belt. The rocks that make up this stock are gray color, predominantly equigranular, occurring sometimes inequigranular. In the central part of the body occurs frequently, the presence of microgranular mafic enclaves. Petrographic studies allowed to identify that this stock is essentially composed of granodiorite with biotite, hornblende and diopside, with the accessories, titanite, allanite, pistacita, zircon, apatite and opaque minerals. Geochemical data show that its rocks are calc-alkaline high potassium microgranular mafic enclaves with showing affinity with the shoshonitic suite. The good linear correlation identified in Harker diagrams between felsic and mafic types is suggestive that the process of magma mixing is responsible for the chemical variation found . The spectra of the rocks have REE fractionation of light REE relative to heavy REE and a weak negative anomaly in Eu, indicating fractionation of plagioclase. These rocks thrown when the tectonic affinity diagrams of Pearce (1996), positioned in the post-tectonic granites field. Isotopic analyzes for zircon sample of biotite-hornblende-granodiorite (187A), were obtained by SHRIMP IIe at Geochronology Laboratory of the Universidade de São Paulo . The zircon crystals are exhibited as elongated prisms with length versus width proportions 3:1. Cathodoluminescence images reveal that these crystals show up clear or oscillatory zoning, typical of magmatic zircon. Data U/Pb zircon ages reveal a concordant age of 618 ± 4 Ma (MSWD = 0.7). This is similar to the age old crystallization obtained by Long et al. 2005 for Coronel João Sá Massif (626 ± 2 Ma) located in the western part of the Macururé Domain, which presents petrographic and geochemical characteristics similar to the Lagoa do Roçado Granodioritic Stock. The age obtained for these rocks suggests that the Lagoa do Roçado Granodioritic Stock is positioned as the late to posttectonic in relation to the Brasiliano Orogeny. / O Stock Granodiorítico Lagoa do Roçado é um corpo com aproximadamente 12 km2, forma alongada, intrusivo nos metassedimentos do Domínio Macururé, localizado na região central da Faixa Sergipana. As rochas que compõe esse stock são de cor cinza, predominantemente equigranulares, ocorrendo por vezes inequigranulares. Na parte central do corpo, ocorre com frequência, a presença de enclaves máficos microgranulares. Os estudos petrográficos permitiram identificar que esse stock é essencialmente constituído por granodioritos com biotita, hornblenda e diopsídio, tendo como acessórios, titanita, allanita, pistacita, zircão, apatita e minerais opacos. Os dados geoquímicos revelam que suas rochas são cálcio-alcalinas de alto potássio com os enclaves máficos microgranulares exibindo afinidade com a suíte shoshonítica. A boa correlação linear identificada nos diagramas de Harker entre os tipos félsicos e máficos é sugestiva de que o processo de mistura de magmas seja o responsável pela variação química encontrada. Os espectros dos ETR das rochas apresentam fracionamento dos ETR leves em relação aos ETR pesados e uma fraca anomalia negativa em Eu, indicando fracionamento de plagioclásio. Essas rochas quando lançadas nos diagramas de afinidade tectônica de Pearce (1996), posicionam-se no campo dos granitos póstectônicos. As análises isotópicas em zircão para a amostra de biotita-hornblendagranodiorito (187A), foram obtidas por SHRIMP IIe no Laboratório de Geocronologia da Universidade de São Paulo. Os cristais de zircão exibem-se como prismas alongados, com proporções comprimento versus largura 3:1. Imagens de catodoluminescência revelam que esses cristais mostram-se límpidos ou com zonação oscilatória, característica típica de zircão magmático. Os dados U/Pb em zircão revelam uma idade concordante de 618 ± 4 Ma (MSWD = 0,7). Esta idade é similar à idade de cristalização obtida por Long et al. 2005, para o Maciço Coronel João Sá (626 ± 2 Ma) localizado na parte oeste do Domínio Macururé, o qual apresenta características petrográficas e geoquímicas similares às do Stock Granodiorítico Lagoa do Roçado. A idade obtida para estas rochas, sugere que o Stock Granodiorítico Lagoa do Roçado posiciona-se como tardio a pós-tectônico em relação à Orogênese Brasiliana.
356

Macrobenthic faunal assemblages of a traditional tidal shrimp pond at Mai Po Marshes Nature Reserve, Hong Kong

Lui, Tak-hang., 呂德恒. January 1999 (has links)
published_or_final_version / abstract / toc / Ecology and Biodiversity / Master / Master of Philosophy
357

Magmatic response to the evolving New Zealand Margin of Gondwana during the Mid-Late Cretaceous

Tappenden, Vanessa Elizabeth January 2003 (has links)
The Mount Somers Volcanic Group (MSVG) and Mandamus Igneous Complex (MIC) are the magmatic manifestations of the transition from convergence to extension at the Gondwana margin, which culminated in the separation of New Zealand from Australia and Antarctica. The MIC has been correlated both geochemically and temporally with the Central Marlborough Igneous Province (CMIP). The MSVG and CMIP are located in the Eastern Province of New Zealand. The MSVG is restricted to the Rakaia terrane, whereas the CMIP is restricted to the Pahau terrane. The Rakaia and Pahau terranes are thick accretionary complexes, which were strongly deformed as a result of prolonged subduction at the Gondwana margin. The Pahau terrane is the younger of the two and continued to be deposited and deformed until the abrupt cessation of subduction, which in the Marlborough sedimentary record occurred in the Motuan (100 - 105 Ma). Following the cessation of subduction, after an interval of 2-7 Ma of relative quiescence and subsidence of the Pahau terrane, the MSVG and MIC were erupted/emplaced. The production of MSVG and MIC magmas occurred simultaneously and the activity was of short-lived duration. SHRIMP geochronology yielded crystallisation ages of 97.0 ± 1.5 Ma to 98.0 ± 1.2 Ma from zircons separated from MSVG rhyolites. The SHRIMP ages are within error of the previously published Rb-Sr age for the MIC. The SHRIMP geochronology also confirmed the presence of inherited zircons which yielded ages consistent with their derivation from the Rakaia terrane. Ar-Ar geochronology confirmed the coeval nature of the MSVG and MIC magmatism, but yielded consistently younger ages (94.5 ± 3 Ma for the MSVG and 94.2 ± 1.7 Ma for the MIC). The systematic differences in ages obtained by SHRIMP and Ar-Ar are believed to be method-dependent. The MSVG comprises a calc-alkaline volcanic assemblage, which ranges in composition from basaltic-andesite lavas (SiO₂ = 54.5%) to high-silica rhyolites and ignimbrites (SiO₂ ≤ 78.1%). The MSVG had an original extent of at least 18 000 km². The magmas from the MSVG had high LILE/HFSE, high LILE/REE and moderately high LREE/HFSE which are characteristic of subduction derived magmas. Geochemical modelling suggests that the MSVG magmas were formed from partial melting of a subduction-modified mantle wedge, with high degrees of crustal assimilation. The assimilant had an isotopic composition similar to that of the Rakaia terrane, which is consistent with the geological setting of the MSVG. The MSVG has ⁸⁷Sr/⁸⁶Sri from 0.7055 to 0.7100 and ¹⁴³Nd/¹⁴⁴Ndi from 0.51254 to 0.51230 (ɛNd +0.5 to -4.2), which reflects varying degrees of contamination by Rakaia terrane. Radiogenic isotope modelling suggests that the MSVG end-members were derived from the same parent magma, which evolved through AFC processes from basaltic-andesite to rhyolite. The modelling strongly suggests that assimilation played a lesser role in the petrogenesis of the Malvern Hills magmas than in the petrogenesis of the other units. AFC modelling requires the degree of assimilation to increase as the magmas evolved. Oxygen isotope data are consistent with high degrees of crustal assimilation, and may indicate that the assimilant had higher ¹⁸O characteristics than the Rakaia terrane samples analysed. The MIC is an alkaline suite which ranges in composition from basalt and gabbro to syenite, trachyte and phono-tephrite. The MIC is interpreted to have formed from enriched asthenospheric mantle, with a composition similar to HIMU (²⁰⁶Pb/²⁰⁴Pbi ranges from 19.2 to 20.3). The samples range in isotopic composition from ⁸⁷Sr/⁸⁶Sri = 0.7030 to 0.7036, ¹⁴³Nd/¹⁴⁴Ndi = 0.51275 to 0.51268 (ɛNd +4.6 to +3.3). The range in isotopic composition is due to varying degrees of contamination by Pahau terrane, which reaches a maximum of 25% but in most samples is < 10%. The MIC is contaminated to a much lesser extent than the MSVG which is interpreted to be related to the thinner nature of the Pahau crust in the mid-Cretaceous. The latest phases of activity in the MIC were subjected to lower degrees of contamination which is interpreted to reflect the passage of magmas through pre-existing pathways. The onset of MSVG and CMIP magmatism coincided with the initiation of major rift-related depositional basins, and the eruption of the MSVG is demonstrably associated with normal faulting. The tectonic trigger responsible for the sudden onset of magmatism and rifting in the Eastern Province terranes was the detachment of the previously subducting slab following the cessation of subduction due to the arrival of the Hikurangi Plateau at the margin and the subsequent stalling of the Pacific spreading centre. The capture of the Gondwana margin led to the propogation of extension into the margin by the divergent Pacific plate. The ensuing extension aided the detachment of the subducting slab beneath the Eastern Province terranes. The slab-detachment promoted decompression melting of the sub-lithospheric mantle wedge to produce the MSVG magmas and triggered the ascent of asthenospheric mantle through the slab window, which melted through decompression to produce the CMIP magmatism. The asthenospheric mantle tapped by the slab detachment episode was highly enriched relative to N-MORB and is akin to the similar age HIMU-OIB affinity melts documented from Antarctica and Australia. The short-lived duration of activity is typical of slab-detachment related magmatism which occurs as a passive response to plate reconfiguration. The similarity in geochemistry of the MIC with OIB-affinity igneous centres in Australia and Antarctica implies an enriched mantle domain of large geographical extent. The distribution of relatively small volumes of OIB magmatism is suggestive of a fossil plume component, which was tapped in response to lithospheric extension producing relatively short-lived HIMU magmatism. The same fossil plume component has previously been implicated in the formation of the Cenozoic West Antarctic Rift System and may be responsible for the late Cretaceous magmatism in the Chatham Islands and Tertiary volcanics of the South Island of New Zealand.
358

Avaliação da influência do meio ambiente do sistema de berçário na imunidade inata de Camarões Litopenaeus vannamei (Boone, 1931). / Evaluation of the influence of the environment of the nursery system in innate immunity of shrimps, Litopenaeus vannamei (Boone, 1931).

Iunes, Renata Stecca 25 March 2013 (has links)
A aquicultura sofre diferentes pressões por um lado o impacto que as doenças causam na produção, e por outro a pressão por parte de grupos ambientalistas e do governo devido ao impacto ambiental. Diferentes soluções foram propostas para esses problemas como probióticos e imunoestimulantes para prevenir e controlar doenças com nenhum ou algum sucesso. Outra opção seria o biofloco para minimizar o impacto ambiental, com excelentes resultados zootécnicos. Porém não sabemos se o sistema de biofloco estimula ou inibe o sistema imune de camarões (Litopenaeus vannamei). Esse é o objetivo desse estudo, saber se o sistema de biofloco altera a contagem total e diferencial de hemócitos, os índices fagocíticos, utilizando ensaio de fagocitose in vitro com Sacaromises cerevisae e a produção de ânion superóxido pelo ensaio de Nitroblue tetrazolium (NBT). Na contagem total de hemócitos nos 2 primeiros meses os animais criados em água clara possuem uma contagem maior que os criados em biofloco enquanto que no 4° mês os animais de biofloco possuem uma contagem maior. Na contagem diferencial no 4°mês as células hialinas estão em maior porcentagem nos animais criados em biofloco enquanto que as granulares e simi-granulares estão em menor porcentagem nesses animais, quando comparamos com os animais criados em água clara. Os índices fagocíticos e a produção de ânion superóxido não apresentam diferença entre os animais criados em água clara e os criados em biofloco. / The aquaculture production suffers different pressure in one hand disease, and in the other its environment impact. Different solutions are offered to solve this problems such as probiotics and immunostimulant to prevent and control the diseases with some or no success. Another option is the biofloc to minimize its environmental impact, with excellent results to zootechincal characteristics. But it is not known whether biofloc stimulate or inhibits the shrimp (Litopenaeus vannamei) immune system. That is what our study aim to answer if the biofloc system affects or not the total and differential hemocytes count, the phagocityc indexes of in vitro phagocytosis with Sacaromises cerevisae and the production of superoxide anion with the Nitroblue Tetrazolium (NBT) assay. At the first 2 month the animal rare in clear water had a higher total hemocyte count, while it was higher in the animals rare in the biofloc at the 4th month. At the 4th month the hyalines cells had a higher concentration in animals rare at biofloc system, while the granular and semi-granular cells had a lower concentration in this animals when compared with the ones rare at the clear water system. The phagocityc indexes and the production of superoxide anion did not have any difference between animals rare at clear water system and biofloc system.
359

Inferência bayesiana em modelos de dinâmica de populações biológicas com termo de perturbação assimétrico / Bayesian inference in biological population dynamic models with skewed and heavy tailed perturbation terms

Silva, Carlos Patricio Montenegro 20 January 2016 (has links)
Neste trabalho de tese, estudamos o modelo de crescimento logístico de populações biológicas utilizando a abordagem de espaço de estados. Os estados não observados são as biomassas anuais, a equação de observação é linear e a equação de estado é não linear. As distribuições de probabilidade utilizadas para os termos de erro de observação aditivos são: Normal, t-student, Skew-normal e Skew-t. As distribuições Log-normal, Log-t, Log-skew-normal e Log-skew-t são consideradas para os erros de observação multiplicativos. A inferência nos modelos é realizada considerando-se métodos Bayesianos e as distribuições a posterior de interesse são aproximadas utilizando-se algoritmos MCMC e a aproximação de Laplace. Apresentamos duas aplicações, a primeira referente a pesca de camarão marinho na costa do Chile, na qual a variável observável é o rendimento médio anual de pesca (captura por unidade de esforço média). Na segunda é considerada a pesca de lagostim vermelho na costa de Chile, na qual além do rendimento médio anual da pesca, observa-se as estimativas anuais de biomassa vulnerável, obtidas através de estudos de área varrida. Para o primeiro conjunto de dados, os modelos com erros de observação multiplicativos têm melhor performance, particularmente os modelos Log-skew-normal e Log-skew-t. Considerando estes resultados, no segundo caso utilizamos somente erros multiplicativos e a distribuição a posteriori preditiva mostra que cada variável observável parece ter sua própria família de distribuição de probabilidades. Além disso, os resultados também revelam uma crescente complexidade do modelo ao incorporar a classe mais geral de distribuições assimétricas. / We study the logistic population growth model using a state-space approach. The non observable states are the annual biomass of the population with a linear observation equation and a non-linear state equation. The probability distribution used for the additives observation error terms are Normal, Student-t, Skew-normal and Skew-t, and Log-normal, Log-t, Log-skew-normal and Log-skew-t for multiplicative observation errors terms. The inference about the parameters of the models is performed using Bayesian methods, with MCMC algorithms and Laplace approximations. We present two applications to real data sets. The first in marine shrimp population off the coast of Chile, where observable variable is the average annual fishing yield. The second application is for the population of the red squat lobster off Chile, where in addition to the average annual fishing yield, a second observable variable was included. In the first case, the multiplicative observational errors models presented the best results. Particularly the Log-skew-normal and Log-skew-t models has the better performances. Considering these results, in the second application we use only multiplicative observation errors models.
360

Utilização de hidrolisado protéico de camarão em rações para tilápia do Nilo (Oreochromis niloticus, L.)

LEAL, Albino Luciani Gonçalves 15 February 2007 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-06T16:53:46Z No. of bitstreams: 1 Albino Luciani Goncalves Leal.pdf: 575820 bytes, checksum: 4cc0fd6d3bf7fe9198563d35eae04f53 (MD5) / Made available in DSpace on 2017-02-06T16:53:46Z (GMT). No. of bitstreams: 1 Albino Luciani Goncalves Leal.pdf: 575820 bytes, checksum: 4cc0fd6d3bf7fe9198563d35eae04f53 (MD5) Previous issue date: 2007-02-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Aquaculture requires high-quality feeds with high protein content. So, the determination of less-expensive sources of protein which provides good growth is advantageous. Shrimp wastes have been identified as an animal protein source with great potential. Shrimp protein hydrolysate (SPH), a derived product obtained from shrimp wastes, was considered an excellent alimentary source and may serve as an useful source of protein and flavorants in food formulations. This work aimed to evaluate the nutritional quality of SPH through growth performance of juvenile Nile tilapia and its protein utilization. SPH was included in isonitrogenous diets at levels of 0, 5, 10 and 20% of fish meal protein replacement (SPH0, SPH5, SPH10 and SPH20) and offered to juvenile Nile tilapia (1.7±0.4 g) stocked in 40-L glass aquaria in a 45-day feeding trial. The inclusion of SPH did not produce statistical differences (P≥0.05) on final weight (27.18, 29.46, 26.02 and 25.19 g), survival (100%), relative weight gain (1,571, 1,624, 1,388 and 1,301%), average daily gain, ADG (0.57, 0.62, 0.54 and 0.52 g day-1), specific growth rate, SGR (7.15, 7.38, 6.85 and 6.73 % day-feed conversion ratio, FCR (1.15, 1.09, 1.13 and 1.17) and protein efficiency ratio, PER (2.26, 2.33, 2.20 and 2.14), respectively. The inclusion of SPH in diets for Nile tilapia statistically affected (P<0.05) the final fish body composition. Protein and ash contents decreased and fat content increased with SPH inclusion levels. This study clearly demonstrates that SPH could be included in diets for Nile tilapia without adverse effects on growth and protein utilization. / A produção aqüícola requer rações de alta qualidade, com alto conteúdo protéico. Assim, a determinação de fontes protéicas de menor custo e que promovam bom crescimento é benéfica. Resíduos de camarão têm sido identificados como uma fonte de proteína animal de grande potencial. Hidrolisado protéico de camarão (HPC) foi considerado como uma excelente fonte alimentar e pode servir como uma adequada fonte de proteína e flavorizante em formulações alimentares. Este trabalho objetivou avaliar a qualidade nutricional do HPC através do desempenho em crescimento de juvenis da tilápia do Nilo e sua utilização protéica. SPH foi incluído em dietas isoprotéicas em níveis de 0, 5, 10 e 20% de substituição da proteína advinda da farinha de peixe (HPC0, HPC5, HPC10 e HPC20) e ofertadas aos peixes (1,7±0,4 g) estocados em aquários de 40 L, por um período experimental de 45 dias. A inclusão do HPC não produziu diferenças estatísticas (P≥0,05) no peso final (27,18, 29,46, 26,02 e 25,19 g), sobrevivência (100%), ganho de peso relativo (1.571, 1.624, 1.388 e 1.301%), ganho de peso diário, GPD (0,57, 0,62, 0,54 e 0,52g dia-1), taxa de crescimento específico, TCE (7,15, 7,38, 6,85 e 6,73 % dia-conversão alimentar, CA (1,15, 1,09, 1,13 e 1,17) e eficiência protéica, EP (2,26, 2,33, 2,20 e 2,14), respectivamente. A inclusão do HPC nas dietas para a tilápia do Nilo afetou estatisticamente (P<0,05) a composição final dos peixes. Os teores de proteína e cinzas diminuíram e o teor de gordura aumentou com os níveis de inclusão do HPC. Este estudo claramente demonstra que o hidrolisado protéico de camarão pode ser incluído em dietas para a tilápia do Nilo sem efeitos adversos em crescimento e utilização protéica.

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