Made available in DSpace on 2015-04-22T22:17:22Z (GMT). No. of bitstreams: 1 monica.pdf: 608033 bytes, checksum: 3fa66bc7ae8660b874f2062bab1562d2 (MD5) Previous issue date: 2010-11-04 / Tambaqui (Colossoma macropomum) is a naturally occurring fish in the Amazon basin, stands out for its remarkable potential to contribute to the regional economy and its wide acceptance in the consumer market. However, one of the contributory factors to reduce the potential for consumption and export is due, in many cases, lack of infrastructure, improper handling since harvest until storage and the inadequate storage directly influencing the raw material quality, resulting the lifetime decreasing for its consumption and marketing. This study aimed to determine the proximate composition and cuts yield of in natura cultivated tambaqui; to determine the influence of frozen storage time on the cuts (rib, tenderloin and flitch) quality through sensory, physicochemical and microbiological analyses during 180 days of frozen storage at -25°C in plastic polyethylene; and the cut type x shelf-life relation. The sensory evaluation of the physical characteristics showed that the quality of analyzed tambaqui cuts remained excellent throughout the experiment. The pH determination, the Total Volatile Basic Nitrogen (TVB-N) and the Thiobarbituric Acid Reactive Substances (TBARS), as well as the microbiological analyses have proved as good indices for freshness evaluation along storage time. Thus, the results allowed concluding that the cut rib was more susceptible to oxidation due to its high fat content, which limits its shelf-life. However, the tambaqui cuts remained appropriate for consumption during 180 days of frozen storage at -25°C in plastic polyethylene, in conditions of correct handling and using good hygiene practices between harvest and storage. / O tambaqui (Colossoma macropomum), peixe de ocorrência natural da bacia amazônica, destaca-se pelo seu notável potencial de contribuição para economia regional e grande aceitação no mercado consumidor. No entanto, um dos fatores contribuintes para redução de seu potencial para consumo e exportação se deve, em muitos casos, a ausência de infraestrutura, manipulação incorreta entre a colheita e armazenamento e estocagem inadequada influenciando diretamente na qualidade da matéria-prima, acarretando diminuição do tempo de vida útil para o seu consumo e comercialização. O objetivo do presente trabalho é determinar a composição centesimal e rendimento dos cortes de tambaqui de cultivo in natura; determinar a influência do tempo de congelamento na qualidade dos cortes (costela, lombinho e posta) por meio de análises sensoriais, físico-químicas e microbiológicas, estocadas durante 180 dias a -25oC e a relação tipo de corte x vida útil. A avaliação sensorial mostrou que os cortes de tambaqui analisados permaneceram com qualidade excelente durante todo o experimento. A determinação do pH, do Nitrogênio das Bases Voláteis Totais (N-BVT) e Substâncias Reativas ao Ácido Tiobarbitúrico (TBARS), assim como os resultados das análises microbiológicas se revelaram como bons índices de avaliação do frescor ao longo do tempo de estocagem. Deste modo, os resultados obtidos permitiram concluir que o corte de costela mostrou-se mais susceptível a oxidação decorrente de seu alto teor lipídico, o que limita o seu tempo de vida útil. No entanto, os cortes de tambaqui mantiveram-se adequados para o consumo durante o período analisado em embalagem plástica de polietileno, em condições de manipulação correta e com uso de boas práticas de higiene entre a colheita e o armazenamento.

Made available in DSpace on 2016-04-28T20:15:31Z (GMT). No. of bitstreams: 1 2006-Rodney Kozlowiski de Azevedo.pdf: 3055958 bytes, checksum: 2e496a089e21831ca514683a7278eb94 (MD5) Previous issue date: 2006-03-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Between December 2004 to November 2005, were collected 50 specimens of Geophagus brasiliensis (Quoy e Gaimard, 1824) and 35 specimens of Astronotus ocellatus (Cope, 1872) from the River Guandu, near to the Station of Treatment of water (ETA) (22?48'32"S, 43?37'35"W), State of Rio de Janeiro, for the study of their communities of metazoan parasites. In G. brasiliensis, nine species of metazoan parasites were collected: 3 digeneans, 1 nematode, 2 hirudineans, 2 acantocephalans and 1 gloquidian. Most of parasite specimens collected were digeneans (95.9 %), being Posthodiplostomum macrocotyle Dubois, 1937 (metacercariae) founded in the eyes the more prevalent species (88.0%) and with highest mean intensity value (12.4), followed for the metacercariae of Austrodiplostomum compactum (Lutz, 1928) (metacercariae) and the hirudinean of family Glossiphoniidae showed prevalence of 14.0% and 10.0% respectively. In A. ocellatus, six species of metazoan parasites were collected: 1 monogenean, 1 nematode, 1 hirudinean, 1 acantocephalan, 1 crustacean, and 1 gloquidian. Most of parasite specimens collected were monogenetic (91.9 %), being Gussevia sp. founded in the gills the more prevalent species (71.4%) and with highest mean intensity value (17.6), followed for the acanthochepalan Polymorphus sp. showed prevalence of 17.1%. The parasite species of G. brasiliensis and A. ocellatus showed the typical aggregated pattern of distribution. / Entre os meses de dezembro de 2004 ? novembro de 2005 foram coletados 50 esp?cimes de Geophagus brasiliensis (Quoy e Gaimard, 1824) e 35 esp?cimes de Astronotus ocellatus (Cope, 1872) provenientes do Rio Guandu, pr?ximo ? barragem da Esta??o de tratamento de ?gua (ETA) (22?48 32 S, 43?37 35 O), Estado do Rio de Janeiro, para o estudo de suas comunidades de metazo?rios parasitos. Em G. brasiliensis foram encontradas nove esp?cies de metazo?rios parasitos: 3 digen?ticos, 1 nemat?ide, 2 hirud?neos, 2 acantoc?falos e 1 larva gloqu?dia. A maioria dos esp?cimes de parasitos coletados foram digen?ticos (95,9%), sendo Posthodiplostomum macrocotyle Dubois, 1937 (metacerc?ria) a esp?cie mais prevalente (88,0%) e com a maior intensidade m?dia (12,4) sendo a maioria dos esp?cimes encontrados parasitando os olhos, seguido pelo digen?tico Austrodiplostomum compactum (Lutz, 1928) (metacerc?ria) e pelo hirud?neo da fam?lia Glossiphoniidae, que apresentaram preval?ncias de 14,0% e 10,0% respectivamente. Em A. ocellatus foram encontradas seis esp?cies de metazo?rios parasitos: 1 monogen?tico, 1 nemat?ide, 1 hirud?neo, 1 acantoc?falo, 1 crust?ceo e 1 larva gloqu?dia. A maioria dos esp?cimes de parasitos coletados foram monogen?ticos (91.9%), sendo Gussevia sp. a esp?cie mais prevalente (71,4%) e com a maior intensidade m?dia (17,6) sendo todos os esp?cimes encontrados parasitando as br?nquias, seguido pelo acantoc?falo Polymorphus sp. que apresentou uma preval?ncia de 17,1%. Os parasitos encontrados em G. brasiliensis e A. ocellatus apresentaram o t?pico padr?o de distribui??o agregado.

The Murray cod (Maccullochella peelii peelii Mitchell 1838) is Australia�s largest freshwater fish. Once highly abundant in the Murray-Darling river system, populations have drastically declined in recent decades. Many causes for this decline have been proposed, including over-fishing, habitat loss and altered river flow regimes. This study hypothesised that elevated salinities have led to selective mortality in some developmental stages, which have in turn depleted stock recruitment and adult populations. The objectives of this study were to determine the optimal, threshold, upper sublethal and lethal salinities for development of eggs, yolk-sac larvae, fry and fingerlings of M. peelii peelii. Investigation the impact of salinity on fertilisation utilised gametes of trout cod (M. macquariensis, Cuvier 1829) instead of M. peelii peelii. Studies were carried out in a controlled laboratory environment using test media prepared from commercial sea salt. The results showed that the eggs of the trout cod hatched only when fertilised and incubated in freshwater, and only larvae hatched in freshwater survived through the yolk absorption period of 12 days. Yolk utilisation efficiencies were not significantly different among the salinities of 0-0.30 g/L. There was no effect of pre- or post- fertilising processes on the salinity tolerances of yolk-sac larvae. No larvae survived at salinities higher than 0.30 g/L during the yolk utilisation period. Lethal salinity concentration in Trout cod and Murray cod larvae was exposure time dependent. The 1 day LC50 of the larvae was 1.97 and 2.33 g/L respectively, compared with the 12 day LC50 values of 0.50 and 0.35 g/L respectively. The threshold (no effect level) salinities of larvae of Trout cod and Murray cod were 0.46 and 0.34 g/L respectively at 12 days exposure. The salinity sensitivities of fry of Murray cod were moderated by increasing pH between pH 6.2 and 8.8, and stimulated by increasing temperatures from 15 to 30°C. The optimal salinity was only slightly affected by temperature. The threshold and upper sublethal salinities varied slightly depending on feeding regime. The salinity sensitivities of fingerlings of Murray cod were: LC50 = 13.7 g/L; optimal salinity from 4.6 to 5.0 g/L ; threshold salinity from 5.9 to 7.4 g/L, and upper sub-lethal salinity from 9.2 to 9.9 g/L � with the range in all cases affected by acclimation period salinity. The blood osmolality at LC50 of the fingerlings was 444 mOsmol/kgH2O or equivalent to 14.2 g/L, and the dehydration rate was 4.8%. The osmolality increased significantly in salinities higher than 9.0 and 6.0 g/L when fish were exposed for a period of 1 day and 41 days respectively. The oxygen consumption increased significantly in salinities higher than 8.0 g/L. Distortion of the notochord and corrosive skin syndrome were major symptoms describing sub-lethal effects found in the embryos, and fry and fingerlings of Murray cod respectively. Noting the risks of extrapolating directly from laboratory to field conditions, it is predicted that when salinity in natural habitats increases above 0.34 g/L a significant impact on Murray cod recruitment will result.

Invasions of non-native species cause problems in ecosystems worldwide, and despite the extensive effort that has been put into research about invasions, we still lack a good understanding for why some, but not other, communities resist these invasions. In this doctoral thesis I test hypotheses on biotic resistance using a large dataset of more than 1000 both failed and successful introductions of freshwater fish into Swedish lakes. We have found that the classic species richness hypothesis is a poor descriptor of introduction success because it fails to acknowledge that resident species contribute to the resistance in different ways. We developed a new measure of biotic resistance, the weighted species richness, which takes into account that the resident species contributes to the resistance with different strength and sign. Further, we correlated performance traits of species in their role as an invader and as a resident species to predict how the biotic resistance of these communities would develop over time. We found a positive correlation between performance traits: Some species have high introduction success, they make a large contribution to the resistance, and they cause extinctions when introduced but do not go extinct themselves when other species establishes, whereas other species are weak performers in these respects. Thus, the biotic resistance of these communities should grow stronger as non-native species accumulates. These results give us clues about what type of communities that should be most sensitive to further invasions, i.e., communities harboring species weak performers.  My results show that the biotic resistance of communities is an important factor in determining invasibility of a community. They also show that methods for quantifying resistance must take into account how interactions are structured in nature. What determine the biotic resistance of a community is the type of interactions that the resident species have with the invader and not the species richness of the community.

Made available in DSpace on 2016-06-02T20:21:25Z (GMT). No. of bitstreams: 1 3396.pdf: 1502102 bytes, checksum: fd6d26f7010be2711e731c2e16e98353 (MD5) Previous issue date: 2010-11-26 / Financiadora de Estudos e Projetos / The São Francisco river comprises one of the largest and most important river basins of Brazil and one of its main characteristics is the variety of fish species. The genus Salminus (Characiformes: Characidae) constitutes a group of migratory fish with great economic importance in fishing and gastronomy. Within this genus, Salminus hilarii (tabarana), due to its high degree of selectivity for the environment and to occupy the top of the food chain, of great importance to the ecosystem and a good indicator of environmental impacts. Many studies on conservation and population genetics have been conducted using molecular markers such as microsatellites, which can provide data on the genetic processes that are acting in a given population. These markers have relatively conserved flanking sequences, which allows the use of primers that were originally designed for other phylogenetically related species. In this study, nine polymorphic microsatellite loci isolated from Salminus franciscanus were used to assess the genetic variation of S. hilarii collected in three localities in the upper São Francisco river basin, aiming to evaluate the level of genetic variation and identify evidence of population structure, providing support for conservation of this group of fish and contributing effectively to maintain the biodiversity of this ecosystem. The cross amplification results were efficient and were able to identify a relatively high level of genetic variation. Moreover, it was possible to observe the absence of genetic structure between populations, suggesting the occurrence of gene flow between them enough to maintenance of the genetic homogeneity of this populations. These results are important tools, since they can provide information for understanding the behavior and biology of these fish to fisheries management and conservation programs. / O Rio São Francisco compõe uma das maiores e mais importantes bacias hidrográficas do território brasileiro e uma de suas principais características é a variedade da ictiofauna. O gênero Salminus (Characiformes: Characidae), constitui um grupo de peixes migradores com grande importância econômica, na pesca esportiva e na gastronomia. Dentro desse gênero, destaca-se Salminus hilarii (tabarana), devido ao seu alto grau de seletividade pelo ambiente e por ocupar o topo da cadeia alimentar. Isso confere à espécie uma grande importância para o ecossistema e a coloca na posição de uma boa indicadora de impactos ambientais. Muitos estudos sobre genética da conservação e de populações têm sido realizados utilizando marcadores moleculares, tais como os microssatélites, capazes de fornecer dados sobre os processos genéticos que estão atuando em uma determinada população. Esses marcadores possuem sequências flanqueadoras relativamente conservadas, o que permite a utilização de primers que foram desenhados originalmente para outra espécie em espécies filogeneticamente próximas. Assim, utilizando nove locos polimórficos de microssatélites isolados de Salminus franciscanus, o objetivo do presente estudo foi analisar a variação genética de S. hilarii coletados em três localidades na bacia do alto São Francisco e identificar evidências de estruturação populacional, produzindo conhecimentos genéticos aos estudos de conservação deste grupo de peixes e contribuindo de maneira efetiva para a manutenção da biodiversidade desse ecossistema. Os resultados obtidos evidenciaram que a amplificação heteróloga foi eficiente e permitiu identificar uma variação genética relativamente alta na espécie em estudo. Além disso, foi possível observar a ausência de estrutura genética entre as populações, indicando a ocorrência de fluxo gênico entre as populações suficiente para manter a homogeneidade genética entre elas. Esses resultados constituem ferramentas importantes, uma vez que contribuem para o entendimento do comportamento e biologia desses peixes, e para programas de manejo de pesca e conservação da tabarana.

Submitted by Ligia Roma Stephan null (ligia.roma@terra.com.br) on 2017-12-03T17:29:12Z No. of bitstreams: 1 Tese Doutorado Ligia R. Stephan.pdf: 1678102 bytes, checksum: 963311d73c5a4e54a01169c577b6df61 (MD5) / Approved for entry into archive by Elza Mitiko Sato null (elzasato@ibilce.unesp.br) on 2017-12-04T14:10:00Z (GMT) No. of bitstreams: 1 stephan_lr_dr_sjrp.pdf: 1678102 bytes, checksum: 963311d73c5a4e54a01169c577b6df61 (MD5) / Made available in DSpace on 2017-12-04T14:10:00Z (GMT). No. of bitstreams: 1 stephan_lr_dr_sjrp.pdf: 1678102 bytes, checksum: 963311d73c5a4e54a01169c577b6df61 (MD5) Previous issue date: 2017-10-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Neste estudo foi avaliada a importância das características limnológicas locais e da predação por peixes na estrutura das comunidades zooplanctônicas, sendo os objetivos e resultados apresentados em dois capítulos distintos: Capítulo 1. Tem por objetivo avaliar a influência dos pulsos de inundação na estrutura funcional e taxonômica das comunidades de microcrustáceos em lagoas marginais. Para atingir o objetivo proposto, foram determinadas a estrutura funcional e taxonômica das assembleias de microcrustáceos coletadas em lagoas marginais ao Rio Turvo em três estações distintas: seca, intermediária e chuvosa. Os resultados encontrados foram comparados entre lagoas e entre estações; também foram comparadas a estrutura das asssembléias das lagoas marginais com amostras de microcrustáceos provenientes de ambientes lênticos com diferentes regimes hidrológicos. Neste estudo também foi avaliado se um período longo de estiagem pode influenciar as dinâmicas sazonais dos microcrustáceos. A estrutura das assembleias dos microcrustáceos com base na classificação funcional e taxonômica apresentaram variações entre lagoas e estações, assim como ambientes aquáticos que não sofrem influência dos pulsos de inundação apresentam uma maior uniformidade funcional. A dinâmica sazonal das assembleias foi afetada pelo período prolongado de estiagem, onde as variações na estrutura das comunidades que existem entre estações foram menos intensas no período de estiagem quando comparado ao ano chuvoso. Os resultados mostram que as características limnológicas das lagoas são influenciadas pelos pulsos de inundação e pelo regime hidrológico, bem como um período prolongado de estiagem é capaz de influenciar a dinâmica sazonal das assembléias de microcrustáceos em lagoas marginais. O estudo também mostra que há uma grande heterogeneidade funcional entre as lagoas, sugerindo que o padrão encontrado para a comunidade zooplanctônica revela mais a importância das características locais associadas ao pulso de inundação do que os efeitos deste sobre a comunidade de toda a planície. Capítulo 2. O segundo capítulo tem por objetivo avaliar se a predação por 6 peixes pode influenciar a estrutura funcional das assembleias de microcrustáceos. A influência da predação sobre a comunidade de microcrustáceos foi avaliada por meio de um experimento de mesocosmo e pela avaliação do conteúdo estomacal dos peixes provenientes das lagoas marginais ao Rio Turvo. A abundância e a estrutura funcional dos microcrustáceos foram influenciadas pela presença dos peixes e das macrófitas aquáticas no experimento, entretanto, para as análises realizadas nas lagoas marginais os resultados mostram que a predação não possui um efeito capaz de influenciar a estrutura das assembleias. Como conclusão, podemos inferir que a presença dos peixes pode ser um fator estruturador das comunidades, mas que em ambientes dinâmicos tais como as lagoas marginais, a influência exercida por alterações nas características locais pode ser um fator mais intenso na estruturação das assembleias de microcrustáceos do que a predação por peixes. / In this study, the importance of local characteristics and predation by fish in the zooplankton community structure was evaluated. The objectives and results were separated in two distinct chapters: Chapter 1. Its objective is to evaluate the influence of flood pulses on the functional and taxonomic structure of microcrustacean communities in oxbow lakes. For the proposed objective, the functional and taxonomic structure of the microcrustacean assemblages from oxbow lakes to the Rio Turvo was determined in three seasons: dry, intermediate and rainy. The results were compared between oxbow lakes and between seasons, as well as between samples from environments with different hydrological regimes. In this study, it was also evaluated if a long period of drought can influence the seasonal dynamics of microcrustaceans. The structure of the microcrustacean assemblages based on the functional and taxonomic classification showed variations between oxbow lakes and seasons; a greater functional uniformity was found on the aquatic environments not influenced by the flood pulses. The seasonal dynamics of the assemblages was affected by the prolonged period of drought, where the variations in the structure of communities between seasons were less intense in the drought year when compared to the rainy year. Our results show the influence of flood pulses on limnological characteristics and on the functional and taxonomic assemblages of microcrustaceans in the oxbow lakes; we also observed that a prolonged period of drought is able to influence the seasonal dynamics of microcrustacean assemblages in oxbow lakes. Chapter 2. The second chapter aims to assess the influence of fish predation on the functional structure of microcrustacean assemblages. The influence of fish predation was evaluated through an mesocosm experiment, and through an evaluation of fish stomach contents sampled in the marginal lakes from Turvo River. In the experiment, the abundance and functional structure of the microcrustaceans were influenced by the presence of fish and aquatic macrophytes, however, results from the oxbow lakes show that predation does not have an effect capable to incluence the structure of the microcrustaceans assemblages. As conclusion, fish predation should have a role in the 8 structure of the communities, although in dynamic environments such as oxbow lakes, the influence of the local characteristics may be a more important factor in the structuring of the microcrustacean assemblages then the fish predation.

HACCP and good manufacturing practices are tools to the safeguard of food safety. Technologic process of fish processing begins by receiving of live fish and ending with stock and expedition of fish products. Stocking is the operation, whereat is able to get to consumer{\crq}s health hazard. Wrong temperature regulation causes multiplication of microorganisms. Stocking proceed at temperature 0 {--} 2 °C, which is stopping increasing of microorganisms. Practically were tracked difference course temperatures during hours and days. During monitoring was average temperature at 10 AM 2.33 {$\pm$} 1.25°C and average temperature at 10 PM was 2.11 {$\pm$} 1.19°C. During monitoring was average temperature 2.10 {$\pm$} 1.03°C. Maximum temperature was monitored in the morning. The temperature raised trough storage of new products. This short - period increasing is able to influence quality of products.

Made available in DSpace on 2015-04-11T13:56:27Z (GMT). No. of bitstreams: 1 Adriana Pontes.pdf: 1647563 bytes, checksum: d9d96e4402b6a1b5ee7e660f48b9a438 (MD5) Previous issue date: 2013-05-03 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The Amazon region population has a habit of acquiring preferably fish "in natura" and / or chilled than in seasons between harvests demand increases in retail outlets consisting of public markets, fairs and supermarkets. To prolong the life business is the development of fundamental techniques associated with maintenance, so the food to keep up their nutritional and organoleptic as well as its consumer security, so the use of Modified Atmosphere Packaging can be efficient to keep these parameters. The aim of this study was to evaluate the influence of modified atmosphere associated with refrigeration technique as prolong the storage matrinxã (Brycon amazonicus) maintained at 2 ± 1 ° C. The fish were processed and washed with sodium hypochlorite solution to 5 ppm, then with saturated sodium chloride solution at 5% for 10 minutes and analyzed for chemical composition, physical-chemical, microbiological and sensory evaluation for Product quality during the time of storage of modified atmosphere packaging (vacuum, CO2 and 100% CO2/N2 60/40%). The results showed higher microbial growth in control samples (untreated) and vacuum, which maintained good quality for about 21 days of storage, when they reached the limits set by law for Staphylococcus coagulase positive, however, showed considerable reduction in bacterial treatments EAM with CO2/N2-60/40% and 100% CO2-good quality that extended for approximately 35 days of storage. Mesophilic bacteria and psychrotrophs not reached the limits of 6.5 log CFU g-1 in all treatments and storage times. The pH shown not to be a good index for evaluating the quality of the product. No changes were detected in lipid oxidation treatments over time. The vacuum treatment was the only one where the TVB-N values reached 29.65 mg 100g-1 at 21 days of storage. The sensory analysis of fish, through the method of quality score did not indicate rejection limits during storage, however, the acceptability test of packaged samples CO2-100% not achieved good results, possibly due to high concentration of carbon dioxide in the samples. The modified atmosphere packaging when associated with chilling is a promising technique to extend the life of matrinxã longer, compared to the conventional methods (vacuum and air), thus supporting the transport over long distances and improving logistics produc. / A população da Região Amazônica tem o hábito de adquirir pescado preferencialmente in natura e/ou refrigerado tanto que nas épocas de entressafras a demanda aumenta nos pontos de venda que consistem em mercados públicos, feiras livres e supermercados. Para prolongar o tempo de vida comercial é fundamental o desenvolvimento de técnicas associadas à conservação, de modo que o alimento mantenha ao máximo suas qualidades nutritivas e organolépticas como também sua seguridade de consumo, portanto, o uso da Embalagem em Atmosfera Modificada poderá ser eficiente para manter esses parâmetros. O objetivo deste trabalho foi avaliar a influência da atmosfera modificada associada à refrigeração como técnica de prolongar o tempo de armazenamento do matrinxã (Brycon amazonicus) mantido a 2 ± 1°C. Os peixes foram processados e lavados em solução com hipoclorito de sódio a 5 ppm, em seguida, com solução de cloreto de sódio a 5% durante 10 minutos e analisados quanto a sua composição centesimal, características físico-químicas, microbiológicas e sensoriais para avaliação da qualidade do produto durante o tempo de armazenamento das embalagens com atmosfera modificada (vácuo, CO2 100% e CO2/N2 60/40%). Os resultados obtidos apresentaram maior crescimento microbiano nas amostras controle (sem tratamento) e vácuo, que mantiveram boa qualidade por acerca de 21 dias de conservação, quando atingiram os limites estipulados pela legislação para Staphylococcus coagulase positiva; no entanto, evidenciou considerável redução bacteriana nos tratamentos com EAM CO2/N2-60/40% e CO2-100% que estendeu a boa qualidade por, aproximadamente 35 dias de armazenamento. As bactérias mesófilos e psicrotrófilos não atingiram os limites estabelecidos de 6,5 log UFC.g-1 em todos os tratamentos e tempos de conservação. O pH mostrou não ser bom índice para avaliar a qualidade do produto. Não foram detectadas variações na oxidação lipídica nos tratamentos ao longo do tempo. O tratamento a vácuo foi o único onde o N-BVT atingiu valores de 29,65 mg.100g-1 aos 21 dias de conservação. A análise sensorial do pescado, através do método de índice de qualidade, não indicou limites de rejeição durante o armazenamento, entretanto, no teste de aceitabilidade das amostras embaladas com o CO2-100% não obteve bons resultados, possivelmente pela elevada concentração de dióxido de carbono nas amostras. As embalagens com atmosfera modificada quando associada à refrigeração é uma técnica promissora para estender a vida útil do matrinxã por mais tempo, comparando-se aos métodos convencionais (vácuo e ar), auxiliando desta forma, no transporte em longas distâncias e melhorando a logistíca do produto

Made available in DSpace on 2015-04-20T12:31:45Z (GMT). No. of bitstreams: 1 Ricardo do Amaral.pdf: 7789911 bytes, checksum: 0c6938c0a8498734d74cedfd87bd7459 (MD5) Previous issue date: 2008-12-09 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The pirarucu, Arapaima gigas is an Amazon native species with high market value and crescent interest by aquaculturists in its rears. As a carnivorous fish, it needs a high level protein diet. The goal of this study was to evaluate the growth performance of pirarucu, Arapaima gigas, juveniles fed with diets produced with ingredients available in the State of Acre-Brazil, notably; blood meal (BM), Brazil nut residue Bertholletia excelsa (BNR) and meat and bone meal (MBM) combined with two energetic sources (animal fat and soybean oil). The study was driven into three phases in a complete randomized design, using different juveniles batch, previously conditioned to feed training to accept dry ration. At the end of each phase, the fish were measured, and one or two were sacrificed in each experimental unit for carcass analysis (whole body), for: moisture, protein, lipid and ash content. During the experiment, fish were kept under a natural photoperiod (12 light: 12 dark). In the first experiment were tested using diets with (0, 3, 6, 9, 12, 15, 18 or 21%) spray-dried blood meal and animal fat as an energy source. A total of 192 pirarucu juveniles(8,5±0,4g) were randomly distributed into the 24 circular fiber glass tanks, supplied with 250 L water (8 fish/tank). Parameters monitored were water temperature (daily, 8:00/14:00h) and pH, dissolved oxygen, ammonia, nitrite, weekly. The fishes fed diets with 9% BM did not present a statistical difference (P>0,05) for evaluated body variables as compared with control diet (0% BM). At the second experiment five experimental rations were used to assess the Brazil nut residue performance at two levels (2 and 4%) as an ingredient able to allow up to 12% of the BM above, the 9% level indicated in the first experiment. One hundred twenty fish (13.10±1,9g) were stocked into 20 circular fiber glass tanks (6/tank) supplies with 300 L water. At this phase, soybean oil was used as energy source. Besides the control treatment with 0% BM and 0% BNR, four diets were tested: (9% xv BM - 2% BNR, 9% BM - 4% BNR) and (12% BM - 2% BNR, 12% BM - 4% BNR). No improvement at the fish performance was observed in animals feed with rations produced with 12% BM as a result of the addition of 2 or 4% BNR. A worse performance was detected in some variables compared with the control diet; even in animals feed with 9% BM diets. In the third set of experiments, three levels of MBM (6, 9 and 12%) were tested besides two energetic sources (animal fat and soybean oil). One hundred ninety two fish (9.21±1,7g) were stocked into 24 fiber glass tanks (8/tank) supplies with 300 L water. No significant statistical difference between treatments (P>0.05) on weight gain, survival and condition faction were detected. The voluntary fed intake showed significant difference among the two treatments with 12% and the 9% MBM + soybean oil compared with the others. The two diets with 6% MBM and the diet with 9% MBM + animal fat showed better protein efficiency rate performance compared to the others. It was concluded that is possible to include BM and MBM up to 9% when animal fat is used as energy source. The inclusion of BNR at 2% or even 4%, / O pirarucu, Arapaima gigas, é uma espécie nativa da Amazônia de alto valor comercial despertando grande interesse no seu cultivo em cativeiro. Por ser um peixe carnívoro, necessita de ração com alto teor protéico. O Objetivo deste trabalho foi avaliar o desempenho zootécnico de juvenis de pirarucu, Arapaima gigas, alimentados com dietas contendo ingredientes disponíveis no Estado do Acre, em particular a farinha de sangue spray-dried (FSSD), o resíduo de castanha-do-brasil Bertholletia excelsa (RC) e a farinha de carne e ossos (FCO) combinados com duas fontes energéticas (banha e óleo de soja). O trabalho de pesquisa foi realizado em três etapas, com delineamento inteiramente casualizado, utilizando três diferentes lotes de alevinos, sendo estes previamente submetidos a treinamento alimentar para aceitação de ração seca. No final de cada fase, os peixes foram submetidos à biometria sendo sacrificados um ou dois animais de cada unidade experimental para realização de análise de carcaça (peixes inteiros), sendo determinados: umidade, proteína bruta, lipídio e cinza. Durante todas as fases os peixes foram submetidos a um fotoperíodo de 12 h luz:12 h escuro. No primeiro experimento foram testadas dietas extrusadas com (0, 3, 6, 9, 12, 15, 18 e 21%) de farinha de sangue spray dried e banha de suíno como fonte de energia. Foram utilizados 192 alevinos 8,5±0,4g, distribuídos em 24 caixas em fibra de vidro abastecidas com 250 L (8 peixes/caixa) sendo monitorados os seguintes parâmetros: temperatura da água (8:00 e 14:00h) diariamente, além de oxigênio, amônia, nitrito e pH (semanalmente). Os peixes alimentados com dietas contendo até 9% de FSSD não apresentaram diferença significativa (P>0,05) em relação à testemunha (0% FSSD) nos parâmetros de desempenho zootécnico avaliados. Este grupo (3, 6 e 9%) de FSSD tiveram desempenho superior (P 0,05) às dietas com (12, 15, 18 e 21%) de FSSD. Na segunda etapa foram elaboradas cinco rações experimentais objetivando avaliar o desempenho do resíduo de castanha (RC) nos teores de (2 e 4%) como ingrediente capaz de viabilizar um incremento para 12% no teor de FSSD possível de ser utilizado, superior portanto aos 9% identificados na primeira etapa como o máximo admissível. Foram utilizadas 20 caixas em fibra de vidro, com capacidade de 500 litros e abastecidas com 300 litros de água cada. Estas foram povoadas com 120 alevinos (6 por caixa) oriundos de uma mesma ninhada com peso médio inicial de 13,10±1,9g. Nesta xiii etapa foi utilizado óleo de soja como fonte de energia. Além da testemunha com 0% de FSSD e 0% de RC, foram testadas quatro formulações: (9% FSSD - 2% RC, 9% FSSD- 4% RC) e (12% FSSD - 2% RC, 12% FSSD - 4% RC). Não foi observada melhora no desempenho dos peixes alimentados com ração contendo 12% de FSSD em função da adição de 2 ou 4% de RC. Ocorreu ainda, um pior desempenho em alguns parâmetros em relação à testemunha, mesmo nos animais arraçoados com dieta contendo 9% de FSSD. Na terceira etapa foram avaliados três níveis de inclusão de farinha de carne e ossos (FCO) (6, 9 e 12%) além de duas fontes de energia (banha de suíno e óleo de soja). Foram utilizados 192 alevinos (9,21±1,7g), distribuídos por 24 caixas em fibra de vidro, com capacidade de 500 litros e abastecidas com 300 litros de água cada. Não foi observada diferença estatística significativa no ganho de peso, sobrevivência e fator de condição entre os tratamentos (P>0,05). O consumo voluntário apresentou diferença significativa (P 0,05) nos dois tratamentos com 12% de FCO e com 9% de FCO com óleo de soja em relação aos demais. A eficiência protéica apresentou melhor desempenho nos dois tratamentos com 6% de FCO e no com 9% de FCO e banha em relação aos demais. Foi identificada a possibilidade de inclusão de até 9% de FSSD e 9% de FCO quando utilizada banha como fonte energética. A utilização do RC nos níveis de 2% e 4% não viabilizou o aumento no teor de FSSD na dieta de 9 para 12%.

Water is one of the most important resources in South Africa. The increased pressure on river systems in SA as a result of human activities and industrial development is evident from the systematic deterioration of the Olifants River (Mpumalanga). While the number of water users grows daily, the river is seen as a convenient disposal site. It is necessary to continually monitor the river to be aware of its status. Regular monitoring also supplements the existing data on water quality, biotic communities and possible points of pollution. The study had the following aims: Firstly to contribute to a larger project on the effect of pollutants on the physiology of fish populations in the Olifants River. This study concentrates on the bioaccumulation of certain metals (i.e. chromium, copper, iron, manganese, nickel, lead, strontium and zinc), in the gills, liver and muscle of Labeo congoro. Standard methods were used to prepare the organs and tissues for metal analysis using atomic absorption spectrophotometry. The following conclusions were reached subsequent to statistical analysis of the results: • The highest mean concentrations of all metals were recorded in the liver of Labeo congoro. • The lowest mean metal concentrations were calculated in the muscle, except for chromium, the concentrations of which were the lowest in the gills. • The highest mean concentration of each metal was recorded in organs / tissues of fish sampled at locality 2. • None of the three localities can be singled out to indicate the lowest mean concentration of each metal. Summary iii The second aim of this study was to determine the 96-hr LC50 (lethal concentration at which 50% of the test population dies) of nickel. Oreochromis mossambicus was used as test organisms for these laboratory studies. A flow through system was used to ensure that the organisms were exposed to the same concentration of nickel for 96 hours. Subsequent to the 96-hr LC50 determination, test organisms were subjected to sublethal exposure of nickel to determine the effects of the various concentrations of the haematology and blood coagulation processes of fish. The following conclusions were drawn from the statistical data processing: • The 96-hr LC50 of nickel for Oreochromis mossambicus is 50 μg.l-1. • The exposure to sublethal concentrations of nickel did effect certain haematological variables • No statistically significant differences in the blood coagulation variables at different sublethal concentrations of nickel were confirmed The results of this study can be used to supplement the database on the water quality and general status of the Olifants River (Mpumalanga). The LC50 of nickel can be used as one of the variables in water quality studies. / Prof. Johan van Vuren