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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.
121

Colorectal polyp outcomes after participation in the seAFOod polyp prevention trial: Evidence of rebound elevated colorectal polyp risk after short-term aspirin use

05 October 2023 (has links)
Yes / The seAFOod polyp prevention trial was a randomised, placebo-controlled, 2 × 2 factorial trial of aspirin 300 mg and eicosapentaenoic acid (EPA) 2000 mg daily in individuals who had a screening colonoscopy in the English Bowel Cancer Screening Programme (BCSP). Aspirin treatment was associated with a 20% reduction in colorectal polyp number at BCSP surveillance colonoscopy 12 months later. It is unclear what happens to colorectal polyp risk after short-term aspirin use. To investigate colorectal polyp risk according to the original trial treatment allocation, up to 6 years after trial participation. All seAFOod trial participants were scheduled for further BCSP surveillance and provided informed consent for the collection of colonoscopy outcomes. We linked BCSP colonoscopy data to trial outcomes data. In total, 507 individuals underwent one or more colonoscopies after trial participation. Individuals grouped by treatment allocation were well matched for clinical characteristics, follow-up duration and number of surveillance colonoscopies. The polyp detection rate (PDR; the number of individuals who had ≥1 colorectal polyp detected) after randomization to placebo aspirin was 71.1%. The PDR was 80.1% for individuals who had received aspirin (odds ratio [OR] 1.13 [95% confidence interval 1.02, 1.24]; p = 0.02). There was no difference in colorectal polyp outcomes between individuals who had been allocated to EPA compared with its placebo (OR for PDR 1.00 [0.91, 1.10]; p = 0.92). Individuals who received aspirin in the seAFOod trial demonstrated increased colorectal polyp risk during post-trial surveillance. Rebound elevated neoplastic risk after short-term aspirin use has important implications for aspirin cessation driven by age-related bleeding risk. ISRCTN05926847. / Efficacy and Mechanism Evaluation Programme. Grant Number: NIHR128210.
122

Polymorphisms in Cyclooxygenase, Lipoxygenase and TP53 genes predict colorectal polyp risk reduction by aspirin in the seAFOod polyp prevention trial

02 November 2023 (has links)
Yes / Aspirin and eicosapentaenoic acid (EPA) reduce colorectal adenomatous polyp risk and affect synthesis of oxylipins including prostaglandin E2. We investigated whether 35 single nucleotide polymorphisms (SNPs) in oxylipin metabolism genes such as cyclooxygenase [PTGS] and lipoxygenase [ALOX], as well as 7 SNPs already associated with colorectal cancer (CRC) risk reduction by aspirin (eg. TP53; rs104522), modified the effects of aspirin and EPA on colorectal polyp recurrence in the randomised 2x2 factorial seAFOod trial. Treatment effects were reported as the incidence rate ratio (IRR) and 95% confidence interval (CI) by stratifying negative binomial and Poisson regression analyses of colorectal polyp risk on SNP genotype. Statistical significance was reported with adjustment for the false discovery rate as the P and q value. Five hundred and forty-two (of 707) trial participants had both genotype and colonoscopy outcome data. Reduction in colorectal polyp risk in aspirin users compared with non-aspirin users was restricted to rs4837960 (PTGS1) common homozygotes (IRR 0.69 [95%CI 0.53,0.90]; q=0.06), rs2745557 (PTGS2) compound heterozygote-rare homozygotes (IRR 0.60 [0.41,0.88]; q=0.06), rs7090328 (ALOX5) rare homozygotes (IRR 0.27 [0.11,0.64]; q=0.05), rs2073438 (ALOX12) common homozygotes (IRR 0.57 [0.41,0.80]; q=0.05), and rs104522 (TP53) rare homozygotes (IRR 0.37 [0.17,0.79]; q=0.06). No modification of colorectal polyp risk in EPA users was observed. In conclusion, genetic variants relevant to the proposed mechanism of action on oxylipins are associated with differential colorectal polyp risk reduction by aspirin in individuals who develop multiple colorectal polyps. SNP genotypes should be considered during development of personalised, predictive models of CRC chemoprevention by aspirin. / Funder(s): Efficacy and Mechanism Evaluation Programme (EME) Award Id(s): NIHR128210. Funder(s): NIHR Senior Investigator grant. Funder(s): Cancer Research UK (CRUK) Award Id(s): C23434/A24939. Funder(s): European Union-BBSRC (UK) Award Id(s): BB/P028233/1.
123

Characteristics of United States Seafood Consumers

Almojel, Suliman 01 January 2016 (has links)
In this thesis, I conducted an analysis of the consumption patterns associated with demographic and socio-economic characteristics, using Tobit and double-hurdle models. Data were collected for 11,574 households from the US Bureau of Labor Statistics for the year of 2014. Specific determinants included household size, age, income, gender, education, race, region, marital status, and whether the household lived in a coastal state. The results reveal that seafood expenditures are sequential decisions. Asian racial groups, households headed by married couples, a large number of members in households, higher income households, and households residing in the Atlantic and Gulf Coasts were variables that significantly impacted seafood expenditures.
124

Small-scale Fisheries and the Global Economy: Understanding Common-pool Resource Governance in the Context of Market Pressures, Neoliberal Policies, and Transnational Institutions

Bennett, Abigail January 2016 (has links)
<p>The purpose of this dissertation is to contribute to a better understanding of how global seafood trade interacts with the governance of small-scale fisheries (SSFs). As global seafood trade expands, SSFs have the potential to experience significant economic, social, and political benefits from participation in export markets. At the same time, market connections that place increasing pressures on resources pose risks to both the ecological and social integrity of SSFs. This dissertation seeks to explore the factors that mediate between the potential benefits and risks of global seafood markets for SSFs, with the goal of developing hypotheses regarding these relationships. </p><p>The empirical investigation consists of a series of case studies from the Yucatan Peninsula, Mexico. This is a particularly rich context in which to study global market connections with SSFs because the SSFs in this region engage in a variety of market-oriented harvests, most notably for octopus, groupers and snappers, lobster, and sea cucumber. Variation in market forms and the institutional diversity of local-level governance arrangements allows the dissertation to explore a number of examples. </p><p>The analysis is guided primarily by common-pool resource (CPR) theory because of the insights it provides regarding the conditions that facilitate collective action and the factors that promote long-lasting resource governance arrangements. Theory from institutional economics and political ecology contribute to the elaboration of a multi-faceted conceptualization of markets for CPR theory, with the aim of facilitating the identification of mechanisms through which markets and CPR governance actually interact. This dissertation conceptualizes markets as sets of institutions that structure the exchange of property rights over fisheries resources, affect the material incentives to harvest resources, and transmit ideas and values about fisheries resources and governance.</p><p> The case studies explore four different mechanisms through which markets potentially influence resource governance: 1) Markets can contribute to costly resource governance activities by offsetting costs through profits, 2) markets can undermine resource governance by generating incentives for noncompliance and lead to overharvesting resources, 3) markets can increase the costs of resource governance, for example by augmenting monitoring and enforcement burdens, and 4) markets can alter values and norms underpinning resource governance by transmitting ideas between local resource users and a variety of market actors. </p><p>Data collected using participant observation, survey, informal and structured interviews contributed to the elaboration of the following hypotheses relevant to interactions between global seafood trade and SSFs governance. 1) Roll-back neoliberalization of fisheries policies has undermined cooperatives’ ability to achieve financial success through engagement with markets and thus their potential role as key actors in resource governance (chapter two). 2) Different relations of production influence whether local governance institutions will erode or strengthen when faced with market pressures. In particular, relations of production in which fishers own their own means of production and share the collective costs of governance are more likely to strengthen resource governance while relations of production in which a single entrepreneur controls capital and access to the fishery are more likely to contribute to the erosion of resource governance institutions in the face of market pressures (chapter three). 3) By serving as a new discursive framework within which to conceive of and talk about fisheries resources, markets can influence norms and values that shape and constitute governance arrangements.</p><p>In sum, the dissertation demonstrates that global seafood trade manifests in a diversity of local forms and effects. Whether SSFs moderate risks and take advantage of benefits depends on a variety of factors, and resource users themselves have the potential to influence the outcomes of seafood market connections through local forms of collective action.</p> / Dissertation
125

Spéciation du mercure dans les produits de la pêche par double dilution isotopique et chromatographie en phase gazeuse couplée à un spectromètre de masse à plasma induit (GC-ICP-MS) / Mercury speciation in seafood by double isotope dilution and gas chromatography inductively coupled plasma mass spectrometry (GC-ICP-MS)

Da fonseca Clemens, Stéphanie 15 September 2011 (has links)
Le mercure est un contaminant présent dans l'ensemble des compartiments de l'environnement et l'homme y est directement exposé via l'alimentation. Actuellement, les organismes gouvernementaux évaluent la sécurité des produits alimentaires en se basant essentiellement sur la concentration totale de cet élément. Cependant, la toxicité du mercure dépend, entre autre, de l'espèce absorbée (dont le méthylmercure, sa forme la plus toxique). Par conséquent, l'analyse de spéciation, c'est à dire la détection et quantification des différentes formes chimiques de cet élément, présente un intérêt croissant. Le principal objectif de ce projet a donc été de développer et de valider, sous assurance qualité, une méthode sensible et d'une grande exactitude, basée sur l'utilisation de la dilution isotopique. Elle sera par la suite appliquée comme méthode de référence par l'agence pour l'analyse en spéciation du mercure dans les produits de la pêche afin de permettre une meilleure évaluation des risques encourus par le consommateur. La première partie de ce travail a porté sur l'étude du cycle biogéochimique du mercure et de l'état de l'art des diverses méthodes de préparation de l'échantillon, de séparation et de quantification du Hg dans les matrices biologiques, afin d'émettre des choix analytiques. Ainsi, les principaux composés mercuriels susceptibles d'être retrouvés dans les produits de la pêche (le méthylmercure et le mercure inorganique) ont été déterminés par couplage GC-ICP-MS et une quantification par dilution isotopique. La seconde partie des travaux a été consacrée à l'optimisation de la méthode de préparation des échantillons et de la technique de quantification. Ces travaux sur différents matériaux de référence certifiés ont montré que des modifications de la distribution naturelle de l'échantillon pouvaient survenir dès l'étape d'extraction, préconisant un marquage isotopique avant extraction solide-liquide par digiPREP des espèces mercurielles et dérivation par propylation par le tétrapropylborate de sodium et agitation rotative. Les résultats expérimentaux ont été traités par dilution isotopique simple et multiple. Les teneurs obtenues ont été similaires, pour l'ensemble des matrices analysées, montrant que peu ou pas de transformation inter-espèces surviennent au cours de la procédure analytique. Une quantification par double marquage isotopique et dilution isotopique simple a donc été conservée. L'évaluation des critères analytique a démontré que la méthode est validée pour la spéciation du mercure dans les produits de la pêche, selon les normes françaises AFNOR NF V03-110 de 1998 et de 2010. La dernière partie des travaux a porté sur l'application de la méthode validée à la spéciation du mercure dans des échantillons biologiques réels, ainsi qu'à la participation à plusieurs essais interlaboratoires d'aptitudes organisés par le CSL-FAPAS sur un échantillon de thon en conserve et par l'IRMM sur le matériau IMEP-109 de homard. / Mercury is a contaminant which is found in all compartments of the environment and to which human beings are directly exposed when eating food. Government agencies assess the safety of food products by using total mercury concentrations. However, its toxicity depends on the species absorbed (among which methylmercury is its most toxic form). Therefore, the analysis of speciation, i.e. detection and quantification of different chemical forms of this element, is of high interest. The main objective of this project was to develop and validate, under quality assurance, a sensitive and highly accurate method, based on the use of isotope dilution. This method will then be applied as a reference method by the agency for speciation analysis of mercury in seafood, in order to better assess risks to the consumer. The first part of this work focused on the biogeochemical cycle of mercury and the state of art of the various methods of sample preparation, separation and quantification of Hg in biological matrices in order to make analytical choices. Thus, mercury compounds (methyl mercury and inorganic mercury) were determined by gas chromatography (GC) coupled with an inductively coupled plasma mass spectrometer (ICP-MS) and quantified by isotope dilution. The second part of the work was dedicated to the optimization of the method of sample preparation and the quantification technique. The work was made on different certified reference materials and showed that changes of the natural distribution of the sample could occur during the extraction step. Therefore, isotopic tracers had been added to the sample before this step. Mercury species were extracted by a solid-liquid extraction by using a digiPREP and derivated by propylation using tétrapropylborate the sodium and a rotary agitation. Data were treated by simple and multiple isotope dilution. Achieved concentrations were similar for all analyzed matrices. Results showed that inter-species transformation hardly occurred during the analytical procedure. This was the reason why the use of two isotopic tracers for quantification by simple isotope dilution was kept. To end, the method was validated for the speciation of mercury in seafood, in respect with the French norms AFNOR NF V03-110 of 1998 and 2010. Finally, the work ended with the applicability of the validated method for mercury speciation analysis in real biological samples and our participation in several inter-laboratory proficiency tests organized by the CSL-FAPAS on a sample of tuna and by the IRMM on the material IMEP-109 (lobster).
126

Les microplastiques et leurs additifs dans les produits de la pêche : développements méthodologiques et prévalence / Microplastics and their additives in seafood products : methodological developments and prevalence

Hermabessiere, Ludovic 12 November 2018 (has links)
L'augmentation de la production de matière plastique depuis les années 1950 combinée à une mauvaise gestion des déchets plastiques ainsi qu'aux mauvais comportements des citoyens conduit à la contamination des écosystèmes terrestres comme marins. L'ingestion par des organismes marins de particules plastiques mesurant moins de 5 mm, appelées microplastiques, a été décrite. L'objectif de ces travaux de thèse était d'évaluer le danger "microplastique" pour le consommateur de produits de la pêche. Afin de répondre à cet objectif, la sélection et la caractérisation d'une méthode permettant de digérer les tissus des produits de la pêche a été. En parallèle, une méthode de Pyrolyse-GC/MS a été optimisée afin d'identifier les microplastiques les plus petits possibles. Ses limites d'applications ont été calculées puis la méthode a été appliquée sur des microplastiques provenant de différents produits de la pêche. Ces deux méthodes ont été appliquées dans la recherche de microplastiques dans deux espèces de bivalves et trois espèces de poissons. Pour les bivalves, la contamination aux microplastiques était comprise entre 0.15 et 0.74 MP/g de chair humide alors que pour les poissons la contamination était assez faible : 0,01 MP/g de tractus gastro-intestinal et 0,001 MP/g de filet. Pour finir, une étude exploratoire de la lixiviation d'un additif plastique en utilisant un modèle de digestion in vitro a été entreprise. Globalement, ces travaux de thèse permettent de proposer des voies d'harmonisation des méthodes pour l'étude des microplastiques dans les produits de la pêche pour, in fine, évaluer le danger pour le consommateur. / Increase in plastic production since the 1950's in combination with plastic waste mismanagement lead to the presence of plastic particle in terrestrial and marine environment. Plastic particles measuring less than 5 mm, called microplastics, are ingested by a wide range of organisms. The goal of this PhD thesis was to evaluate the microplastic hazard for seafood consumers. firstly, method for digesting seafood tissue without degrading plastic polymer was selected and applications limits were determined for digestion of fish digestive tracts. Concurrently, a Pyrolysis-GC/MS method was optimized, limit of detection were determined and this method was applied on environmental samples. Both methods were used to study microplastics contamination in bivalve and fish species used for human consumption. Bivalve contamination was between 0.15 and 0.74 MP/g of tissue wet weight whereas contaminations in fish were low. Indeed, digestive tracts were contaminated by in mean 0.01 MP/g of tissue wet weight and muscles were contaminated by in mean 0.001 MP/g of tissue wet weight. Lately, leaching of a plastic additive was studied using an in vitro enzymatic model of digestion. However, such phenomenon was not highlighted. Overall, these results will help to standardize the study of microplastics in seafood products.
127

台灣傳統市場之水產舖經營分析與管理策略─以北投市場為例 / Operation of seafood booth in traditional market—BeiTou market as the model

陳怡誠, Chen, Casey Yi-Chen Unknown Date (has links)
No description available.
128

Managing sea cucumber fisheries and aquaculture : Studies of social-ecological systems in the Western Indian Ocean

Eriksson, Hampus January 2012 (has links)
Collecting sea cucumbers to supply the high value Chinese dried seafood market is a livelihood activity available to many people in the Western Indian Ocean (WIO), making it an important part of local economies. These fisheries are generally not successfully managed and tropical sea cucumber fisheries show continuing signs of decline. This thesis takes a social-ecological systems approach to guide better management of sea cucumber fisheries and aquaculture in the WIO. Papers 1 and 2 analyse the fishery situation in Zanzibar and find that in the absence of effective management institutions and income alternatives among fishers, leading to dependence, there are unsustainable expanding processes. Paper 3 compares the unmanaged fishery in Zanzibar to the highly controlled situation in Mayotte. In Mayotte, a protection effect is evident and the commercial value of stocks is significantly higher than in Zanzibar. The analysis of the situation in Mayotte demonstrates the importance of matching the fishery – management temporal scales through prepared and adaptive management to avoid processes that reinforce unsustainable expansion. Paper 4 analyses sea cucumber community spatial distribution patterns at a coastal seascape-scale in Mayotte establishing baseline patterns of habitat utilization and abundance, which can be used as reference in management. Paper 5 reviews the potential for sea cucumber aquaculture in the WIO. The review illustrates that this activity, which is currently gaining momentum, does so based on inflated promises and with significant social-ecological risks. Emphasis for improvements is, in this thesis, placed on the importance of prepared and adaptive institutions to govern and control expanding processes of the fishery. These institutional features may be achieved by increasing the level of knowledge and participation in governance and by integration of sea cucumber resources management into higher-level policy initiatives. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.</p>
129

Efeito antimicrobiano do ozônio no processamento da tilápia do nilo, Oreochromis niloticus (Linnaeus, 1758) / Antimicrobial effect of ozone in the Nile tilapia, Oreochromis niloticus (Linnaeus, 1758) processing

Silva, Andressa Medeiros de Mendonça 28 August 2015 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-09-01T20:41:50Z No. of bitstreams: 1 AndressaMMS_DISSERT.pdf: 1954199 bytes, checksum: e72c0bd0dda36d90e31b5cf4a2e9fbc3 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-09-06T15:19:56Z (GMT) No. of bitstreams: 1 AndressaMMS_DISSERT.pdf: 1954199 bytes, checksum: e72c0bd0dda36d90e31b5cf4a2e9fbc3 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-09-06T15:20:09Z (GMT) No. of bitstreams: 1 AndressaMMS_DISSERT.pdf: 1954199 bytes, checksum: e72c0bd0dda36d90e31b5cf4a2e9fbc3 (MD5) / Made available in DSpace on 2017-09-06T15:20:29Z (GMT). No. of bitstreams: 1 AndressaMMS_DISSERT.pdf: 1954199 bytes, checksum: e72c0bd0dda36d90e31b5cf4a2e9fbc3 (MD5) Previous issue date: 2015-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to evaluate the efficiency of ozonated water as an antimicrobial agent in the Nile tilapia (O. niloticus) processing. Samples of whole tilapia and fillets were washed with cold water (11 ° C), without ozone (0 ppm - control) and with ozone (0.5; 1.0; 1.5 ppm) for 0; 5; 10; and 15 minutes. Microbiological parameters (total count of mesophilic, Staphylococcus aureus positive coagulase counts, fecal coliforms and the presence of Salmonella sp.) and physicochemical parameters (pH, color, TBA) were evaluated in order to check the microbiological load reduction and possible changes on pH, color and lipid oxidation (TBA) of fillets. The most effective ozone concentration on reducing the microbial load of the surface of tilapia was 1.5 ppm, reducing the initial populations of mesophilic bacteria in 91.78%. At this concentration (1.5 ppm), it was effective within the first 5 min., reducing the microbial load of 71.23%. In fillet washing, 1.5 ppm ozone concentration also showed the greatest reduction of mesophilic bacteria 70.19%. The treatment with ozonated water of fillets showed no influence on the pH and color of the fillets, however, there was an increase in the TBA value (1.5 ppm of O3 for 15 min.), showing that lipid oxidation occurred, but below the thresholds that make them unfit for consumption. The results showed that the ozonated water has been effective in reducing the microbial load of the fish during processing. The cost of electricity consumption used for ozone generation demonstrated its feasibility of use / O objetivo com o presente trabalho foi avaliar a eficiência da água ozonizada como agente antimicrobiano no processamento da tilápia do Nilo (O. niloticus). Amostras de tilápia inteira e filés foram imersas em água gelada (11°C) sem ozônio (0 ppm - controle) e com ozônio (0,5; 1,0; 1,5 ppm) durante 0; 5; 10; e 15 minutos. Parâmetros microbiológicos (contagem total de mesófilos, contagem de Staphylococcus aureus coagulase positivo, coliformes termotolerantes e presença de Salmonella sp.) e físico-químicos (pH, cor, TBA) foram avaliados a fim de verificar diminuição da carga microbiológica e possíveis alterações de pH, cor do filé, e oxidação lipídica (TBA). A concentração de ozônio mais efetiva sobre a diminuição da carga microbiana da superfície da tilápia foi a de 1,5 ppm, reduzindo as populações inicias de bactérias mesófilas em 91,78%. Nesta concentração (1,5 ppm), a eficácia foi nos primeiros 5 min., reduzindo a carga microbiana em 71,23%. Na imersão do filé, a concentração de ozônio de 1,5 ppm também apresentou a maior redução de bactérias mesófilas 70,19%. O tratamento dos filés com água ozonizada não demonstrou influência sobre o pH e cor dos filés, no entanto, observou-se um aumento dos valores de TBA (1,5 ppm de O3 por 15 min.), demonstrando que ocorreu oxidação lipídica, mas inferior aos limites que os deixam impróprios para o consumo. Os resultados demonstraram que a água ozonizada foi eficiente na redução da carga microbiana do pescado durante o processamento. O custo do consumo de energia elétrica utilizada para geração do ozônio demostrou sua viabilidade de uso / 2017-09-01
130

Fontes de fósforo em rações orgânicas para alevinos e juvenis de tilápia do nilo (Oreochromis niloticus) / Phosphorus sources in organic feed for the nile tilapia fingerlings and juveniles (Oreochromis niloticus)

Dieterich, Fabiana 23 February 2010 (has links)
Made available in DSpace on 2017-07-10T17:48:21Z (GMT). No. of bitstreams: 1 Fabiana_Dieterich.pdf: 548442 bytes, checksum: a6ddac63b91985f11bbd5ff7b79a725e (MD5) Previous issue date: 2010-02-23 / Fundação Araucária / Two experiments were conducted in the Aquaculture Laboratory of the Group of Studies on Aquaculture Handling (GEMAq, in the Portuguese acronyms), which, by the way, belong to the State University of the West of Paraná, in Toledo. In experiment 1, we utilized 270 Nile tilapia fingerlings (Oreochromis niloticus) with 0.88±0.33g average weight, assigned into 18 500-liter tanks, in a total random fashion, indoor system. Each experiment dealt with three treatments and six repetitions, with a daily renewal of water equivalent to 10%, done through siphonage in order to eliminate feces and occasional feed rests. The fingerlings and the juveniles was feed organic, coming from corn, wheat and soybean meal, containing 32% and 28% of gross protein (GP), for the first and the second experiment, respectively. The diets were supplemented with industrial waste seafood flour (SF), bicalcium phosphate (BF), or their combination (SF + BF), in which case both the sources contributed with 50% of phosphorus amount. Physico-chemical parameters were evaluated (OD, pH, conductivity and temperature), as well as water analyses, one in the beginning, another after 30 days and a last one in 60 days of the experiment, aiming to check the values of ammonia, nitrite, phosphrus and nitrate. At the end of the experiment, then, the evaluations focused on livestock performance data and on the fish s carcasses chemical composition. Water physico-chemical parameters fit the recommendation for the species in both the experiments. Evaluated phosphorus sources didn t influence (P<0.05) livestock performance, or the carcass centesimal composition and the water quality for the raising of Nile tilapia fingerlings. For the juveniles of Nile tilapia fingerlings, the evaluated treatments did not bring a significant difference (p>0.05) as to the survival rate. However, there was a significant difference (p<0.05) for the final weight, the weight gain and the food conversion, what indicates that the fish feds with diets supplemented with bicalcium phosphate obtained low final weight and weight gain when compared to the fish fed with the diets supplemented with phosphorus coming from seafood flour and with phosphorus supplementation equally divided, 50% BF, 50% SF and a worse food conversion when compared with the treatment based on phosphorus coming only from SF, but it didn t differ (p>0.05) from the treatment SF and BF. The values obtained for phosphorus in water in experiments 1 and 2 were above the accepted by the resolution 357/2005 of CONAMA, what indicates the necessity of improvement in relation to the food handling and/or alternate treatment of the generated effluent. For fingerlings, it is either possible to use the bicalcium phosphate, seafood flour, or their combination as source of phosphorus. However, for Nile tilapia juveniles it is recommended to use the seafood waste meal as for the phosphorus supplementation, or also the combination of SF and BF (it is important to note that each source must supplement 50% of the phosphorus demands) / Foram realizados dois experimentos com objetivo de avaliar duas fontes de fósforo, farinha de peixe e fosfato bicálcico, e sua combinação em rações orgânicas para alevinos e juvenis de tilápia do Nilo (Oreochromis niloticus). Foram utilizados 270 alevinos com peso inicial de cerca de 0,88±0,33g distribuídos em 18 tanques experimentais com capacidade para 250L e 180 juvenis de tilápia do Nilo com peso inicial de 13,63±1,05g distribuídos em 18 tanques experimentais com capacidade para 500L, em um delineamento inteiramente casualizado em um sistema indoor . Cada experimento constou de três tratamentos e seis repetições, com uma taxa de renovação diária de água equivalente a 10%, realizada através de sifonagem para eliminar as fezes e eventuais sobras de ração. Os alevinos e juvenis foram alimentados com rações de origem orgânica a base de milho, trigo e farelo de soja contendo 32% e 28% de proteína bruta (PB), para o primeiro e segundo experimento, respectivamente. As rações foram suplementadas com farinha de resíduos da industrialização de pescado de origem marinha (FP), fosfato bicálcico (FB) ou sua combinação (FP+FB), neste caso com 50% de cada fonte como fonte suplementar de fósforo. Foram monitorados parâmetros físico-químicos (OD, pH, condutividade e temperatura) e realizadas análises da água no início, aos 30 dias e 60 dias do experimento para avaliação de amônia, nitrito, fósforo e nitrato. Ao final do experimento foram avaliados índices zootécnicos e de composição química da carcaça dos peixes. Os parâmetros físico-químicos da água enquadraram-se no recomendado para a espécie nos dois experimentos. As fontes de fósforo avaliadas não influenciaram (P<0,05) os parâmetros zootécnicos como composição centesimal da carcaça e qualidade da água de cultivo dos alevinos de tilápia. Para juvenis de tilápia do Nilo os tratamentos avaliados não proporcionaram diferença significativa (p>0,05) quanto a sobrevivência, entretanto houve diferença significativa (p>0,05) para peso final, ganho de peso e conversão alimentar, indicando que os peixes alimentados com a dieta suplementada com fosfato bicálcico obtiveram menor peso final e ganho de peso quando comparados aos peixes alimentado com as dietas com suplementação de fósforo a base de farinha de peixe e com suplementação de fósforo a base de 50% de FB e 50% de FP e pior conversão alimentar que o tratamento com suplementação de fósforo a base de FP, mas não diferindo (p>0,05) do tratamento FP + FB. Os valores obtidos para fósforo na água nos experimentos 1 e 2 ficaram acima do preconizado pela Resolução 357/2005 do CONAMA, indicando a necessidade de melhorias quanto ao manejo alimentar e/ou tratamento alternativo do efluente gerado. Para alevinos é possível utilizar fosfato bicálcico, farinha de peixe ou sua combinação como fonte de fósforo, no entanto, para juvenis de tilápia do Nilo recomenda-se como suplementação de fósforo em rações orgânicas a farinha de resíduos de peixes ou a combinação de FP e FB, sendo que cada fonte deve suplementar 50% da demanda de fósforo

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