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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.
91

Variation in wild stocks of the freshwater prawn Macrobrachium australiense (Holthuis, 1950): Environmental influence on external morphology.

Dimmock, Amanda January 2004 (has links)
Macrobrachium australiense is a common freshwater prawn found throughout most of eastern and inland Australia. Debate has been ongoing on the systematics of this species due to high morphological variation: past studies have relied on external morphology assessments to describe genetic relationships between populations. An individual's morphological phenotype results however, from an interplay of genetic factors, environmental, and interactions between genes and the environment. The current study examined the strength of genetic constraint on morphological traits in this species. Examination of over 1000 M. australiense museum specimens collected from across the species' extensive natural range, documented high phenotypic variation with no regional pattern of variation. Within regions, 88% of variation in morphological traits in mature males and juveniles was present between local rivers. Therefore, morphological variation is not structured at the regional level. If there is a strong genetic base to morphological variation then populations in a single river system must be evolving essentially in isolation. More intensive sampling within a single river system demonstrated high morphological variation in 600 M. australiense individuals from 18 populations within a geographically connected system. Populations separated by as little as 1km showed significant morphological differences in 50% of mature male traits. If morphological variation is primarily genetically based, then populations within a river system were evolving independently at a very fine spatial scale. This hypothesis was tested by breeding morphologically divergent populations of M. australiense in a controlled environment to isolate genetic influences on morphological variation. Low heritability for morphological traits in five divergent populations raised under identical environments established that there is no strict genetic control on morphological variation in these M. australiense populations. Morphologically homogenous offspring resulted from wild parents that had exhibited significant differences at 73% of traits examined. Therefore, the fundamental assumption that morphological variation in M. australiense is dictated by strict genetic control is not supported in these representative populations. Moreover, significant variation in 41% of morphological traits was produced by raising a single population at different environmental temperatures (28oC and 22 oC). A single homogenous stock of M. australiense should not produce morphologically divergent offspring if genetic factors are the major influence of phenotypic expression. Crossing of pure line divergent stocks resulted in hybrid offspring with significant differences in 50% of female morphological traits, whereas male offspring varied for only 31% of morphological traits. This result suggests that female morphological expression is affected more strongly by genetic factors than male offspring in this trial. The growth and maturation of external morphological traits during development in M. australiense is under limited genetic constraint, especially in the later phases of growth. Only 17% of traits varied between juvenile stocks in the last three months of development when individuals were exposed to identical environmental conditions. Maturation size was homogenous, except for females in the absence of maturing males in divergent stocks exposed to identical environmental conditions. Females were much larger in size and shape of morphological traits in the absence of mature males in the population. Thus environmental factors strongly influence phenotypic expression of external morphology in M. australiense. Past problems with the taxonomy of this species are therefore understandable as many important traits used in systematics appear to be under limited genetic control. Past evolutionary studies based on morphological diversity in this species therefore may be unreliable as the traits used to identify divergent forms may not provide a true reflection of genetic divergence.
92

Níveis de cálcio, fósforo, lipídeo e proteína na dieta inerte do camarão-da-malásia Macrobrachium rosenbergii, na fase larval /

Guerrero Alvarado, Camilo Ernesto. January 2009 (has links)
Orientador: Wagner Cotroni Valenti / Banca: Helenice Pereira de Barros / Banca: José Eurico Possebon Cyrino / Banca: Gilberto Moraes / Banca: Wilson Massamitu Furuya / Resumo: A formulação de uma dieta balanceada que atenda as exigências dos minerais cálcio e fósforo nas larvas de Macrobrachium rosenbergii, é importante para garantir maior produtividade na larvicultura. Assim, avaliou-se o efeito de diferentes níveis de cálcio e fósforo na dieta sobre as principais variáveis de produção. O delineamento experimental foi em blocos casualizados, em esquema fatorial 3x3, correspondente a três níveis de cálcio (0,35; 1,00 e 1,90%) e três de fósforo (0,70; 1,50 e 2,30%), com três repetições realizadas em blocos temporais. Dois dias após a eclosão, as larvas passaram a ser alimentadas com quantidades crescentes de náuplios de Artemia. A partir do 11º dia (zoea VII), iniciou-se a co-alimentação, fornecendo-se as dietas-teste juntamente com os náuplios de Artemia até o final do ciclo de larvicultura. No 27º dia de cultivo, quando aproximadamente 90% das larvas metamorfosearam-se em pós-larvas (PL), realizou-se a despesca. Foi calculada a taxa de sobrevivência, a biomassa final de PL, a porcentagem de larvas e a produtividade (PL L-1) em cada tratamento. Observou-se que as larvas de M. rosenbergii alimentadas com dieta inerte contendo 0,35 ou 1,07% de Ca total, e 1,50% de P total (1,15% de P disponível) melhoraram significativamente a sobrevivência e o número de pós-larvas produzidas por litro ao final da larvicultura. A inclusão de 1% de P na forma de NaH2PO4 e unicamente o Ca proveniente da dieta basal (0,35%) são adequados para melhorar o desempenho produtivo desta espécie. / Abstract: The formulation of a balanced diet, which provides the requirements of calcium and phosphorus minerals for Macrobrachium rosenbergii larvae is important to guarantee good productivity of post-larvae. Hence, the effect of different levels of calcium and phosphorus in the inert diet on the principal production variables was evaluated during the hatchery. It was used a randomized block experimental design, in a 3x3 factorial scheme, with three levels of calcium (0.35; 1.00 and 1.90 %) and three levels of phosphorus (0.70; 1.50 and 2.30 %), with three replicates. Two days after hatching, larvae started feeding on increasing quantities of Artemia nauplii. Co-feeding started at the 11th day (zoea VII), when test-diets plus Artemia nauplii were supplied up to the end of the rearing cycle. In the 27th day, when approximately 90% of the larvae turned into post larvae (PL), harvest was done. Survival rate, final biomass of PL, percentage of larvae and productivity (PL L-1) were calculated in all treatments M. rosenbergii larvae fed on inert diet containing 0.35 or 1.07 % of total Ca and 1.50 % of total P (1.15 % of P available) had significantly improved survival rate and productivity. Inclusion of 1.0 % of total P and only the dietary Ca from the basal diet (0.35%) are adequate to improve the productive performance on this specie. / Resumen: La formulación de una dieta balanceada que atienda las exigencias de los minerales calcio y fósforo en las larvas de Macrobrachium rosenbergii, es importante para garantizar mejor productividade en la larvicultura. Asi, se evaluó el efecto de diferentes niveles de calcio y fósforo en la dieta sobre las principales variables de producción. El diseño experimental fue en bloques completamente al azar, en esquema factorial 3x3, correspondiente a tres niveles de calcio (0,35; 1,00 e 1,90%) y tres de fósforo (0,70; 1,50 e 2,30%), con tres repeticiones realizadas en bloques temporales. Dos días después de la eclosión las larvas pasaron a ser alimentadas con cantidades crecientes de náuplios de Artemia. A partir del 11º día (zoea VII), se inició la alimentación conjunta, ofreciendo las dietas-teste acompañadas por los náuplios de Artemia hasta el final del ciclo de larvicultura. El 27º día del cultivo, cuando aproximadamente 90% de las larvas se metamorfosearon en postlarvas (PL), se realizó la cosecha. Fue calculada la tasa de sobrevivencia, biomasa final de PL, el porcentaje de larvas y la productividad (PL L-1) en cada tratamiento. Se observó que las larvas de M. rosenbergii alimentadas con dieta inerte conteniendo 0,35 ó 1,07% de Ca total, y 1,50% de P total (1,15% de P disponible) mejoraran significativamente la sobrevivencia y el número de postlarvas producidas por litro al final de la larvicultura. La inclusión de 1% de P en la forma de NaH2PO4 y únicamente el Ca proveniente de la dieta basal (0,35%) son adecuados para mejorar el desempeño productivo de esta especie. / Résumé: La formulation d'un régime alimentaire équilibré que puisse répondre aux besoins de calcium et de phosphore des larves de Macrobrachium rosenbergii est très important pour assurer des meilleures productivités à la fin de la larveculture. L'effet de différents niveaux de calcium et de phosphore sur le régime alimentaire a été evalué sur les principaux variables de production. Une délineation complétement au hasard en schème factoriel 3x3, a été utilisé, en correspondant à trois niveaux de calcium (0,35; 1,00 et 1,90%) et trois niveaux de phosphore (0,70; 1,50 et 2,30%). Chaque traitement a eu 3 répétitions. Deux jours après l'éclosion les larves ont été nourries avec des quantités croissantes de nauplii d'Artemia. A partir du onzième jour (zoea VII), la coalimentation a été introduite en fournissant les diètes-teste en plus des nauplii d' Artemia jusqu'à la fin du cycle de larveculture. Au 27ème jour du cycle où 90% des larves, à peu près, se sont déjà méthamorphosées en pos-larves (PL), la récolte de fin d'élevage a été faite. Le taux de survie, la biomasse finale de PL, la pourcentage de larves et la productivité (PL L-1) ont été calculés pour chaque traitement. On a pu observer que les larves de M. rosenbergii qu'ont été nourries par une diète inerte de 0,35 ou 1,07% de calcium total et 1,50% de P total (1,15% de P disponible) ont eu leurs taux le survie beaucoup ameliorés aussi bien que le numero de pos-larves qu'ont été produites par litre à la fin da la larveculture. L'inclusion de 1% de P sur la forme de NaH2PO4 et le Ca venu de la diète basal (0,35%) sont suffisants pour améliorer la production de cette espèce. / Doutor
93

Estudo da qualidade dos efluentes gerados em diferentes fases do cultivo do camarão-da-amazônia Macrobrachium amazonicum /

Nogueira, Mayra. January 2008 (has links)
Orientador: Luiz Augusto do Amaral / Banca: Ângela Cleusa de Fátima Banzatto do Carvalho / Banca: Lúcia Helena Sipaúba Tavares / Banca: Márcia Noelia Eler / Banca: Mônica de Andrade Morraye / Resumo: Nas últimas décadas, a carcinicultura de água doce é um dos setores que mais cresceu dentro da aqüicultura. Muitas pesquisas têm sido realizadas a fim de buscar metodologias para se ter uma produção sustentável, ou seja, lucrativa e com baixo impacto ambiental. Neste contexto, o presente estudo analisou a qualidade da água de abastecimento e efluente em todas as fases do cultivo do camarão-da-amazônia, Macrobrachium amazonicum. Nas fases de larvicultura e berçário o sistema de cultivo adotado foi com recirculação de água e densidade de estocagem de 80 larvas/L e 7 pós-larvas/L, respectivamente. Foram realizadas análises microbiológicas representada pelo Número Mais Provável de Escherichia coZi e análises fisicas e químicas para a verificação de pH, temperatura, sólidos totais suspensos, demanda bioquímica de oxigênio, nitrogênio total, nitrito, nitrato, da água de abastecimento e efluente de 5 tanques de cultivo, em cada uma dessas fases. Na fase de crescimento final, foram analisados 12 viveiros de fundo natural, com fluxo contínuo de água e densidade de estocagem de 40, 60, 80 e 100 juvenis/m2, cujo delineamento experimental utilizado foi blocos inteiramente casualizados com 4 tratamentos e 3 repetições. Foram realizadas as mesmas análises microbiológicas, fisicas e químicas citadas nas fases de larvicultura e berçário, com o acréscimo nesta da análise de demanda química de oxigênio. Nesta fase, ainda realizou-se o balanço dos nutrientes: nitrogênio total, sólidos totais suspensos e demanda bioquímica de oxigênio para a obtenção de mais infonnações sobre o comportamento dessas variáveis na dinâmica dos viveiros. Em todas as fases, os resultados obtidos revelaram que a qualidade da água do efluente estava de acordo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In recent decades, the freshwater carcinicultura is one of the sectors that more grew inside of the aquaculture. Many research have been carried out in order to develops methodologies for sustainable production, that is, lucrative and with low environrnent impact. In that context, the present study we analyzed the quality of the water of supply and effluent in alI the stages of the culture of the Macrobrachium amazonicum. In the stages of lavircultura and nursery the system of adopted culture was with recirculation of water and density of 80 stockage of larvae/L and 7 juveniles/L, respectively. Were conducted microbiological analysis represents for the number of Escherichia colí and physical and chemical analyses for the verification of pH, temperature, total suspended solids, biochemical oxygen demand, total nitrogen, nitrite and nitrate, of the water of supply and efluent of 5 tanks of culture, in each one of the stages. In the final stages of growth, 12 ponds of deep natural had been analyzed, with continuous flow of water and density of stockage of 40, 60, 80 and 100 juveniles/m 2, whose used experimental delineation was fulIy randomized blocks with 4 treatments and 3 repetitions. The same microbiological, physical and chemical analyses cited in the larvicultura and nursery had been carried out, with the addition in this of the analysis of chemical oxygen demando At this stage, was become balance of the nutrients: total nitrogen, suspended total solids and biochemical oxygen demand for the attainment of more information on the behavior of these variable in the dynamics of the ponds. At all stages, the results showed that water quality of the effiuent was in accordance with the current law and that did not have significant difference between the water and effluent... (Complete abstract click electronic access below) / Doutor
94

Estruturas do olho do Macrobrachium amazonicum (Heller, 1862) (Crustacea, Decapoda, Palaemonidae): estudo utilizando microscopia óptica e de varredura.

BOULHOSA, Silvio Márcio Pereira 19 January 2011 (has links)
Submitted by Ana Rosa Silva (arosa@ufpa.br) on 2012-07-25T13:10:02Z No. of bitstreams: 2 Dissertacao_EstruturasOlhoMacrobrachium.pdf: 8585266 bytes, checksum: 79f76f2af18563d9af67fef1b033d62d (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2012-07-25T13:10:39Z (GMT) No. of bitstreams: 2 Dissertacao_EstruturasOlhoMacrobrachium.pdf: 8585266 bytes, checksum: 79f76f2af18563d9af67fef1b033d62d (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2012-07-25T13:10:39Z (GMT). No. of bitstreams: 2 Dissertacao_EstruturasOlhoMacrobrachium.pdf: 8585266 bytes, checksum: 79f76f2af18563d9af67fef1b033d62d (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2011-12 / O gênero Macrobrachium contém mais de 120 espécies e ocorre nas regiões tropicais e subtropicais de todo o mundo (VALENTI, 1987). São camarões de água doce da família Palaemonidae e da ordem Decapoda (RAFINESQUE, 1815; LATREILLER, 1802). No Brasil existem 18 espécies, até agora classificadas, distribuídas ao longo da bacia amazônica (MELO 2003). Entre estas, o Macrobrachium amazonicum (HELLER, 1862) conhecido popularmente como camarão-sossego ou camarão-canela, amplamente empregados na carcinicultura. Os crustáceos dispõem de estruturas sensitivas localizadas no cefalotórax, que permitem receber estímulos do meio para localizar e capturar o alimento (BARNES, 1998). Os olhos compostos estão presentes em todas as classes de crustáceo. Assim, a hipótese levantada nessa pesquisa foi que no Macrobrachium amazonicum, estes olhos são do tipo de superposição reflexiva, onde o aparelho dióptrico e o rabdômero se estendem em camadas e está separado por uma zona clara não pigmentada. Neste trabalho temos como objetivos: Avaliar os aspectos morfológicos do olho do Macrobrachium amazonicum em microscopia eletrônica de varredura; Caracterizar a morfologia das células fotorreceptoras; Descrever as estruturas morfológicas do olho do M. amazonicum; Caracterizar as relações morfométricas entre o olho e as demais estruturas do M. amazonicum. Os animais foram adquiridos no distrito de Mosqueiro nos períodos de chuvas, março de 2009 e março de 2010, com pescadores no município de Santa Bárbara, área metropolitana de Belém, e transportados para o laboratório em caixas de isopor, sendo mantidos em quarentena em um recipiente contendo uma solução de permanganato de potássio a 1,3 mg/L (CARNEIRO et al., 005). Os animais foram fixados em Davidson e Karnovisky, em seguida os olhos de cada animal foram cuidadosamente seccionados e colocados em frascos plásticos. Nas relações biométricas foram realizadas a análise de variância com α = 0,05, foi realizada com Bio Estat 5.0 para os comprimentos do olho látero-lateral e ântero-posterior dos quatro morfotipos, e SigmaPlot 11.0 e regressão linear simples, para as variáveis olho total e cefalotórax. Observou-se que o tamanho médio do cefalotórax, do corpo, do olho é respectivamente: 21,03 mm; 70,62 mm e 4,52 mm, sendo que, o peso médio do camarão foi de 7,97 g. Os valores máximos registrados dessas estruturas foram de 31,95 mm para o cefalotórax; 100,10 mm para o tamanho do corpo; 6,80 mm para o tamanho do olho e de 20,54 g para o peso do camarão. Após análise histológica foram identificadas as seguintes estruturas (Figs. 13 e 14 A-B): córnea, cone cristalino, pigmento distal, haste do cone, zona clara, cutícula, retina, rabdoma, fibras do nervo óptico e lamina. Com relação à microscopia eletrônica de varredura, foram selecionadas para observação as principais estruturas e especialmente o arranjo em seção transversal quadrada dos omatídeos (Figs. 16 A-B). As análises morfométrica e morfológica (por histologia e microscopia eletrônica de varredura) apontaram características próprias de Macrobrachium amazonicum adultos oriundos da região metropolitana de Belém. Estes achados incluem uma óptica de superposição reflexiva com olhos adaptados a percepção de estímulos luminosos. / The genus Macrobrachium contains more than 120 species and occurs in tropical and subtropical regions worldwide (VALENT, 1987). They are freshwater shrimp family Palaemonidae and order Decapoda (RAFINESQUE, 1815; LATREILLE, 1802). In Brazil there are 18 species, classified until now distributed throughout the Amazon Basin (MELO 2003). Among these, Macrobrachium amazonicum (HELLER, 1862) popularly known as shrimp quiet or shrimp cinnamon, widely used in shrimp farming. Crustaceans have sensory structures located on the cephalothorax, which allow then to receive the stimulus means to locate and capture food (BARNES, 1998). The compound eyes are present in all classes of crustacean. Thus, this research hypothesis was that in Macrobrachium amazonicum, these eyes are kind of overlay reflective, where the dioptric apparatus and rhabdom extend in layers and are separated by a clear non-pigmented area. In this work we have the following objectives: To evaluate the morphological aspects of the eye of Macrobrachium amazonicum scanning electron microscopy; characterize the morphology of the photoreceptor cells; describe the morphological structures of the eye of M. amazonicum; characterize the morphometric relationships between the eye and other structures of M. amazonicum. The animals were acquired in the district of ‘Mosqueiro’ in the rainy season, in March 2009 and March 2010, with fishermen in Santa Barbara city, the metropolitan area of Belém, and transported to the laboratory in polystyrene boxes, being held in quarantine in a vessel containing a solution of potassium permanganate at 1.3 mg / L (CARNEIRO et al., 2005). The animals were fixed in Davidson Karnovisky then the eyes of each animal were carefully sectioned and placed in plastic. Relations were performed in biometric analysis of variance with α = 0.05, was performed with Bio Stats 5.0 for the lengths of the side of the eye and anterior-posterior of the four morphotypes, and SigmaPlot 11.0 and simple linear regression for the variables eye total and cephalothorax. It was observed that the average size of the cephalothorax, the body, the eye is respectively: 1.03 mm, 70.62 mm and 4.52 mm, and the average weight of shrimp was 7.97 g. The structures of these maximum values recorded were 31.95 mm for the cephalothorax; 100.10 mm body size, 6.80 mm for the size of the eye and 20.54 g for the weight of the shrimp. Histological analysis identified the following structures (Fig. 13:14 AB): cornea, crystalline cone, pigment distal shaft of the cone, clear zone, cuticle, retina, rabdoma, optic nerve fibers and laminates. With respect to scanning electron microscopy, were selected to observe the main structures and especially the arrangement of ommatidia square cross section (Figs. 16 AB). The morphological and morphometric analysis (by histology and scanning electron microscopy) showed characteristics of Macrobrachium amazonicum adults from the metropolitan region of Belém. These findings include a reflective optical superposition eyes fitted with the perception of light stimuli.
95

Dinâmica populacional do camarão cascudo Macrobrachium amazonicum (Heller, 1862) da Ilha de Combú – Belém-PA

SILVA, Márcia Cristina Nylander 28 April 2006 (has links)
Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-07-28T11:59:43Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_DinamicaPopulacionalCamarao.pdf: 1487593 bytes, checksum: 1448cba46f8b91ed66792fc19bd028cd (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-09-10T16:49:48Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_DinamicaPopulacionalCamarao.pdf: 1487593 bytes, checksum: 1448cba46f8b91ed66792fc19bd028cd (MD5) / Made available in DSpace on 2014-09-10T16:49:48Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_DinamicaPopulacionalCamarao.pdf: 1487593 bytes, checksum: 1448cba46f8b91ed66792fc19bd028cd (MD5) Previous issue date: 2006 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os camarões do gênero Macrobrachium, pertencentes à família Palaemonidae, são muito utilizados tanto na aqüicultura como explorados através da pesca comercial. Dentre as espécies do gênero, M. amazonicum destaca-se por ser largamente consumido, apresentar carne saborosa e possuir larga distribuição geográfica. Considerando a importância sócio-econômica deste recurso para o Estado do Pará, este trabalho tem o objetivo de descrever a dinâmica populacional e avaliar o estoque do camarão cascudo M. amazonicum da Ilha do Combú (Pará). A coleta de dados ocorreu entre os meses de março de 2002 a fevereiro de 2003 (exceto agosto) onde aproximadamente 500 gramas de camarão eram obtidos mensalmente. Em laboratório, os indivíduos eram medidos (comprimento total e comprimento da carapaça) e pesados (peso total). Para a determinação da fecundidade, depois de removida a massa ovígera, os ovos foram transferidos para uma solução com água na qual foram retiradas alíquotas para a contagem dos ovos sob um microscópio estereoscópio. Para a determinação dos parâmetros populacionais foi utilizado o Programa FISAT (Fish Stock Assessment Tools). As fêmeas alcançam comprimento máximo menor que os machos, porém seus comprimentos médios mensais foram superiores ao longo de todo o ano. Ocorreu uma proporção significativa favorável, às fêmeas nos meses de julho, setembro, janeiro e fevereiro e nas classes de comprimento 2,5-2,9 cm e 6,5 a 9,4 cm. A fecundidade mostrou uma relação linear com o comprimento total onde o número de ovos variou de 40 a 3.375 ovos/fêmea. Evidenciou-se 3 coortes para a espécie que nascem entre dezembro-janeiro/02, setembro-outubro/02 e abril-maio/03. Considerando diversas metodologias, os parâmetros de crescimento foram similares entre si, na qual o K para os machos foi maior e variou entre 0,7 a 1,36 cm/mês e nas fêmeas variou entre 0,66 a 0,91 cm/mês. O L∞ (para a maioria das metodologias) também foi superior para os machos (12,37 a 17,66 cm) quando comparado com as fêmeas (12,66 a 14,14 cm). Os valores estimados da mortalidade total Z pela curva de captura foram maiores nos machos (valores entre 3,15 e 6,13) quando comparado com as fêmeas (valores de 3,86 a 6,89) o mesmo ocorreu para o método de Beverton e Holt, para machos (valores entre 5,43 a 9,31) e fêmeas (valores de 4,43 a 4,92). O tamanho de primeira captura (Lc), foi maior nas fêmeas (5,88 cm) quando comparados com os machos (4,25 cm). A EMSY (taxa de exploração para a obtenção do rendimento máximo sustentável) de machos e fêmeas está abaixo de E (taxa de explotação atual) indicando uma sobrepesca dos estoques de M. amazonicum na Ilha do Combú. / Shrimps of genus Macrobrachium, family Palaemonidae, are largely utilized for aquaculture and also are explored by commercial fisheries. Amongst the species of this genus, M. amazonicum is largely consumed, shows valued meat and is largely distributed. Considering the social-economic importance of this resource in the State of Pará, this study has the objective of describing the population dynamics and assesses the stock of barky shrimp M. amazonicum in island of the Combú (Pará). Data was collect from March 2002 to February 2003 (except august) where approximately 500 grams of shrimp were monthly obtained. In laboratory, individuals were measured (total length and length of carapace) and weighted (total weight). For determining the fecundity, after removed the eggs mass, were transferred to a water solution were they were counted under a microscopy. For the determination of the population parameters, it was utilized the Program FISAT (Fish Stock Assessment Tools). Females showed smaller maximum length when compared to males, although their average mensal lengths through all year were superior to those of males. It was registered a significant positive sexual proportion to females in July, September, January and February and for the length classes 2.5-2.9 cm and 6.5 to 9.4 cm. The fecundity showed a positive linear relation with the total length and the number of eggs varied from 40 to 3375 eggs/female. It was registered 3 cohorts for the species which were born in December-January/02, September-October/02 and April-May/03. Considering the different methodologies, growth parameters were similar between them and K for males was superior when compared to females and varied from 0.7 to 1.35 cm/month. For females K varied from 0.66 to 0.91 cm/month. L∞ (for most methodologies) was also superior for males (12.37 to 17.66 cm) when compared to females (12.66 to 14.14 cm). Estimated values of total mortality Z for the capture curve had been bigger in the higher for males (values from 3.15 to 6.13) than for females (values from 3.86 to 6.89) the same occurred for method of Beverton and Holt, males (values between 5.43 to 9.31). The length at first capture (Lc) was superior for females (5.88 cm) than for males (4.25 cm). The EMSY (explotation rate for the maximum sustainable yield) for males and females is below the E (exploitation rate) indicating that M. amazonicum of island of the Combú is over-exploited.
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Evolution and function of cellulase genes in Australian freshwater crayfish

Crawford, Allison Clare January 2006 (has links)
The most abundant organic compound produced by plants is cellulose, however it has long been accepted that animals do not secrete the hydrolytic enzymes required for its degradation, but rely instead on cellulases produced by symbiotic microbes. The recent discovery of an endogenous cDNA transcript encoding a putative GHF9 endoglucanase in the parastacid crayfish Cherax quadricarinatus (Byrne et al., 1999) suggests that similar cellulase genes may have been inherited by a range of crustacean taxa. In this study, the evolutionary history of the C. quadricarinatus endoglucanase gene and the presence of additional GHF9 genes in other decapod species were investigated. The activity of endoglucanase and endoxylanase enzymes within several cultured decapod species were also compared. The evolutionary history of the C. quadricarinatus endoglucanase gene was assessed by comparing intron/exon structure with that of other invertebrate and plant GHF9 genes. The coding region of the gene was found to be interrupted by eleven introns ranging in size from 102-902 bp, the position of which was largely conserved in both termite and abalone GHF9 genes. These structural similarities suggest GHF9 genes in crustaceans and other invertebrate taxa share a common ancestry. In addition, two introns were observed to share similar positions in plant GHF9 genes, which indicates this enzyme class may have been present in ancient eukaryote organisms. The presence of GHF9 genes in C. quadricarinatus and various other decapod species was then explored via degenerate primer PCR. Two distinct GHF9 gene fragments were determined for C. quadricarinatus and several other Cherax and Euastacus parastacid freshwater crayfish species, and a single GHF9 gene fragment was also determined for the palaemonid freshwater prawn Macrobrachium lar. Phylogenetic analyses of these fragments confirmed the presence of two endoglucanase genes within the Parastacidae, termed EG-1 and EG-2. The duplication event that produced these two genes appears to have occurred prior to the evolution of freshwater crayfish. In addition, EG-2 genes appear to have duplicated more recently within the Cherax lineage. The presence of multiple GHF9 endoglucanase enzymes within the digestive tract of some decapod species may enable more efficient processing of cellulose substrates present in dietary plant material. Endoglucanase and endoxylanase enzyme activities were compared in several parastacid crayfish and penaeid prawn species using dye-linked substrates. Endoglucanase activity levels were higher in crayfish compared with prawn species, which corresponds with the known dietary preferences of these taxa. Endoglucanase temperature and pH profiles were found to be very similar for all species examined, with optimum activity occurring at 60°C and pH 5.0. These results suggest endoglucanase activity in penaeid prawns may also be derived from endogenous sources. Additional in vitro studies further demonstrated crayfish and prawn species liberate comparable amounts of glucose from carboxymethyl-cellulose, which indicates both taxa may utilise cellulose substrates as a source of energy. Endoxylanase temperature and pH profiles were also similar for all crayfish species examined, with optimal activity occurring at 50°C and pH 5.0. These results suggest xylanase activity in crayfish may originate from endogenous enzymes, although it is unclear whether this activity is derived from GHF9 enzymes or a different xylanase enzyme class. In contrast, no endoxylanase activity was detected in the three prawn species examined. Together, these findings suggest a wide range of decapod crustacean species may possess endogenous GHF9 endoglucanase genes and enzymes. Endoglucanases may be secreted by various decapod species in order to digest soluble or amorphous cellulose substrates present in consumed plant material. Further biochemical studies may confirm the presence and functional attributes of additional endoglucanase genes and enzymes in decapods, which may ultimately assist in the design of optimal plant based crustacean aquaculture feeds.
97

Ecologia, pesca e dinâmica populacional do camarão-da-Amazônia - Macrobrachium amazonicum (Heller, 1862) (Decapoda:Palaemonidae) – capturado na região das ilhas de Belém - Pará - Brasil

SILVA, Bianca Bentes da January 2011 (has links)
Submitted by Edisangela Bastos (edisangela@ufpa.br) on 2013-02-27T21:48:15Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_EcologiaPescaDinamica.pdf: 15774193 bytes, checksum: 84fbee848617191688380b75a37147d8 (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2013-03-04T16:45:31Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_EcologiaPescaDinamica.pdf: 15774193 bytes, checksum: 84fbee848617191688380b75a37147d8 (MD5) / Made available in DSpace on 2013-03-04T16:45:31Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Tese_EcologiaPescaDinamica.pdf: 15774193 bytes, checksum: 84fbee848617191688380b75a37147d8 (MD5) Previous issue date: 2011 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / FAPESPA - Fundação Amazônia de Amparo a Estudos e Pesquisas / DAAD - Serviço Alemão de Intercâmbio Acadêmico / Deutscher Akademischer Austauschdiens / A partir de coletas biológicas mensais na Baía do Guajará e Ilha do Mosqueiro, foram obtidas amostragens de Macrobrachium amazonicum para estudos de reprodução, densidade, relações morfométricas e dinâmica de populações. Adicionalmente, dois outros desenhos amostrais foram utilizados para estudo da capturabilidade da espécie sobre influência de dois tipos de iscas e três tamanhos de armadilhas e de sua distribuição espacial em dois canais perenes do mesmo estuário. Os resultados apontam para diferença na captura de M. amazonicum quando se utiliza isca de farelo de babaçu, porém a diferença é unicamente na abundância sendo que a estrutura populacional não é modificada. A espécie é mais abundante no período seco, corroborando a idéia de maior capturabilidade dos recursos pesqueiros. A ilha do Combu é o local onde os espécimes são mais encontrados e ainda com maiores tamanhos. As fêmeas são significativamente maiores e mais pesadas que os machos, denotando a diferenciação no metabolismo devido à reprodução. A proporção de machos é maior nas menores classes de comprimento, o que pode indicar um aumento na predação de machos de menores tamanhos devido ao seu comportamento mais agressivo que o das fêmeas ou simplesmente por que os machos que atingem comprimentos maiores que as fêmeas sejam mais intensamente predados pela pesca, havendo o recrutamento apenas dos machos menores. O tamanho de primeira maturação (comprimento da carapaça) para ambos os sexos resultou em 11,5mm (11,5 mm nos machos e 11,2mm nas fêmeas). A reprodução em M. amazonicum é do tipo contínua ou periódica com um aumento gradativo entre os meses de outubro a março. Os locais mais abrigados, como regiões mais internas de canais de maré ou furos (comuns no estuário amazônico) são locais preferencialmente procurados por fêmeas maduras para a desova e crescimento dos juvenis. Os parâmetros de crescimento da curva de von Bertalanffy obtidos, foram bastante similares entre os sexos, sendo L∞ = 44,8mm e K = 0,35 para os machos e L∞ = 46,5 e K = 0,31 para as fêmeas. As taxas de mortalidade e explotação obtidas apontam para um estado limítrofe de explotação do recurso, neste sentido, o manejo deverá ser tratado com bastante cuidado. A taxa atual de explotação encontra-se no seu limite máximo de sustentabilidade. Nesta situação, qualquer aumento do esforço poderá ocasionar um estado de sobre-explotação de crescimento. Aliado ao estado de quase comprometimento dos estoques de M. amazonicum, a situação sócio econômica dos pescadores também não é diferente dos demais sistemas pesqueiros do litoral do Pará: baixa escolaridade, atuação deficiente das entidades de classe, cadeia produtiva complexa e que desprivilegia os seus principais atores. Sugere-se o monitoramento estatístico da produção; a delimitação do tamanho mínimo de captura em 4,5cm de comprimeto total; a proibição da pesca com matapis em áreas de cabeceira de furos e canais de maré; um censo de usuários e a utilização de modelos bioeconômicos que contemplem os principais aspectos de sua cadeia biológica e produtiva. / In monthly biological samples of M. amazonicum in Guajará Bay and Mosqueiro island, were studied reproduction, density, morphometric relationships and population dynamics. Two other sample designs was realized in two perennial the same estuary. Results indicate differences in capture of this species using different bait of meal, but is solely on the abundance and population structure does not change. The species is most abundant in the dry season, supporting the idea higher catchability of fishery resources. In Combu island was found species with larger sizes. Females are significantly larger and heavier than males, indicating the differentiation in metabolism due to reproduction. Sex ratio of males is higher in smaller size classes, which may indicate an increase in predation on smaller sizes of males due to their behavior more aggressive than the females or males simply because they reach lengths larger than females are more heavily preyed upon by fishing, with the recruitment of only the smaller males. First maturation length for both sexes resulted in 11.5 mm – carapace length - (11.5 mm in males and 11.2 mm in females). Reproduction in M. amazonicum is continuous or periodic a gradual increase during the months from October to March. The most common sites housed, as inner regions of tidal channels or holes (common in Amazon estuary) sites are preferentially sought by mature females for spawning and juvenile growth. Von Bertalanffy growth parameters obtained were very similar between the sexes, where L ∞ = 44.8 mm and K = 0.35 for males and L ∞ = 46.5 and K = 0.31 for females. Mortality and exploitation obtained was in maximum sustainability and the management should be treated fairly care. In this situation, any increase in effort may result a state of over-exploitation of growth. Allied to near commitment of the stocks of M. amazonicum of the socio economic fishing is no different from other systems of coastal fishery Para: poor education, poor performance of professional associations, chain productive complex and that its main underprivileged. We suggest the statistical monitoring of production, the delineation of the minimum capture length in 4.5cm; suppression of fishing with matapis in headwater areas of creeks and tidal channels, a census of users and the use of models bioeconomic that include major aspects of its biological and productive chain.

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