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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.
21

Clonagem, caracterização e análise filogenética das subunidades alfa e beta do hormônio luteinizante de pirarucu (Arapaima gigas) / Cloning, characterization and phylogenetic analysis of the alpha and beta subunits of luteinizante hormone of pirarucu (Arapima gigas)

Thais Cristina dos Anjos Sevilhano 22 April 2015 (has links)
O Arapaima gigas, conhecido popularmente como pirarucu é uma espécie de peixe pertencente à ordem dos Osteoglossiformes, nativo da Bacia Amazônica e autóctone da Bacia de São Francisco e do Nordeste. É considerado um dos maiores peixes de água doce do mundo, chegando, na fase adulta, a três metros de comprimento e mais de 200 kg de peso, possuindo, portanto, uma grande importância para a alimentação e o comércio da região. Infelizmente esta espécie pertence à lista de animais sobre explorados do IBAMA, também em perigo de extinção, devido especialmente à pesca predatória e à sua dificuldade reprodutiva em cativeiro. Por estas razões, desenvolvemos o presente trabalho de clonagem e caracterização de um de seus hormônios da reprodução (gonadotrofinas), em particular o hormônio luteinizante (LH). Esta glicoproteína é constituída por duas subunidades ligadas de forma não covalente: a subunidade α (GTHα) comum também ao hormônio folículo estimulante (FSH) e a subunidade β, que confere a especificidade de sua ação biológica. Tanto o cDNA do ag-GTHα quanto aquele do ag-LHβ foram sintetizados pela reação de transcriptase reversa (RT) e pela reação de cadeia de polimerase (PCR) utilizando vários primers, a partir do RNA total obtido das glândulas hipofisárias de A.gigas. O cDNA de GTHα apresentou um comprimento total de 767 pb incluindo uma cadeia poli-A de 20 adeninas. Foi identificada uma região codificante (ORF) de 348 pb iniciando com o primeiro códon (ATG) na posição 58 e o códon de parada (stop) na posição 403. O sinal de poliadenilação (ATTAAA) foi localizado 18 pb antes da cauda poli-A. A região codificante traduz um peptídeo de 115 aminoácidos, com um sítio de clivagem do peptídeo sinalizador situado entre o aminoácido 24 e 25. A proteína apresenta portanto um suposto peptídeo sinal de 24 aminoácidos e um peptídeo maduro de 91 aminoácidos, que quando alinhado com outras espécies de peixes, mostra a conservação de 10 resíduos de cisteína, 3 prolinas e dois potenciais sítios de glicosilação entre os aminoáciodos 51-53 (NIT) e os aminoáciodos 77-79 (NHT). O cDNA de ag-LHβ apresenta um comprimento total de 711 pb, incluindo uma cadeia poli-A de 18 adeninas. Foi identificada uma região codificante (ORF) de 426 pb, iniciando com primeiro códon (ATG) na posição 47 e terminando na posição 469. O sinal de poliadenilação (AATAAA) foi localizado 18 pb antes da cadeia poli-A. A região codificante traduz um peptídeo sinalizador situado entre o aminoácido 24 e 25. Com isso, temos um peptídeo sinalizador de 24 e um peptídeo maduro de 117 aminoácidos que apresenta a conservação de 12 resíduos de cisteína, 6 prolinas e um sítio potencial de N-glicosilação identificado entre os aminoácidos 10-12 (NQT), enquanto um segundo possível sítio de N-glicosilação (alterado para QTT), entre os aminoácidos 27-29, foi perdido. Como na subunidade GTHα, a maior porcentagem de identidade de LHβ foi com os Cypriniformes (75.6%) enquanto a menor foi com os Gadiformes (53.8%). A análise filogenética realizada utilizando as sequências de FSHβ e LHβ de 41 espécies de peixes, incluido o A.gigas, confirmou os dados publicados relativos à subunidade GTHα, posicionando o A.gigas como grupo irmão dos Clupeocephala e os Elopomorpha (Anguilliformes) como grupo mais basal entre os teleósteos . / Arapaima gigas, popularly known as pirarucu, is a species of fish that belongs to the order of Osteoglossiformes, originating from the Amazon, São Francisco river basin and the North East of Brazil. It is considered one of the largest fresh water fishes in the world, reaching when adult three meters in length and more than 200 kg in weight. It is therefore very important for food and for the regional industry. Unfortunately, this species belongs to the list of overexploited animals from IBAMA and is in danger of disappearing due to fishing exploitation and to its reproductive difficulties, especially in captivity. For these reasons, we developed this project for the cloning and characterization of one of its hormones of reproduction (gonadotropins), namely luteinizing hormone (LH). This glycoprotein is formed by two subunits non-covalently bound: the α subunit (GTHα), in common with follicle-stimulating hormone (FSH) and the β subunit, that provides the specificity of its biological action. Both cDNAs of ag-GTHα and of ag-LHβ have been synthesized via reverse transcriptase (RT) and polymerase chain reaction (PCR) utilizing several primers, starting from total RNA extracted from A. gigas pituitary glands. The cDNA of ag-GTHα showed a total lenght of 767 bp, including a poli-A tail with 20 adenines. A coding reagion (ORF) of 348 bp, was also identified, starting from the first codon (ATG) at position 58, with the stop codon at position 403. The polyadenylation signal (ATTAAA) was identified 18 bp before the poly-A tail. This coding sequence translates a 115 amino acid peptide showing a signal-peptide cleavage site between amino acid 24 and 25. It has therefore a putative signal peptide with 24 and a mature peptide with 91 amino acids that, when aligned with other species of fish, presents 10 conserved residues of cysteine, 3 of proline and two potential glycosylation sites at amino acids 51-53 (NIT) and amino acids 77-79 (NHT). The cDNA of ag-LHβ has instead a total length of 711 bp, including a poly-A tail of 18 adenines. A coding region of 426 bp was identified, starting with the first codon (ATG) at position 47 and having the stop codon at position 469. The polyadenylation signal (AATAAA) was found 18 bp before the poly-A tail. The coding region translates a signal-peptide located between amino acid 24 and 25. It has a signal peptide with 24 and a mature peptide with 117 amino acids that presents 12 conserved residues of cysteine, 6 of proline and a potential N-glycosylation site at amino acid 10-12 (NQT), while a second possible N-glycosilation site at amino acid 27-29 (altered into QTT), was last due to the substitution of an asparagine with a glutamine. As for the case of ag-GTHα, the highest percent of identity was found with Cypriniformes (75.6%), while the lowest was with Gadiformes (53.8%). The phylogenetic analysis carried out with cDNA sequences of LHβ and FSHβ of 41 different fish species, confirmed previous published data concerning ag-GTHα, locating A.gigas as the sister group of Clupeocephala and the Elopomorpha (Anguilliformes) as the most basal group of all living teleosts.
22

Effets de l’exposition parentale au diuron sur le méthylome et transcriptome de l’huître du Pacifique Crassostrea gigas / Effects of parental exposure to diuron on methylome and transcriptome of the Pacific oyster Crassostrea gigas

Rondon Sallan, Rodolfo 11 December 2015 (has links)
L’huître du pacifique Crassostrea gigas est l'espèce marine la plus cultivée avec une production supérieure à 4 millions de tonnes pour l'année 2010. En France, C. gigas est cultivée depuis la fin des années 1970. Cependant, cette espèce souffre d’un syndrome de mortalité estivale depuis les années 1980, avec une amplification depuis 2008 qui touche jusqu'à 100 % des naissains. Ce syndrome de mortalité est un phénomène multifactoriel, basé sur l’interaction de nombreux facteurs: stress environnementaux, caractéristiques physiologiques et génétiques de l’huître, présence et virulence de pathogènes. L’huître du pacifique C. gigas est une espèce estuarienne qui est soumise aux pressions anthropiques comme la pollution du milieu côtier. Ces événements représentent des sources potentielles de stress en zones ostréicoles. Cependant, les connaissances sur les effets des polluants comme les pesticides sur C. gigas restent fragmentaires. Les périodes d’épandage d’herbicides coïncident parfois avec la période de reproduction des huîtres, raison pour laquelle nous considérons que ces produits chimiques pourraient affecter la génération suivante d'huîtres. Parmi les pesticides, le diuron est le plus fréquemment détecté sur les côtes françaises, avec une concentration maximale rapportée de 0,78 µgL-1. L'exposition directe aux herbicides affecte le transcriptome des huîtres qui est le premier niveau de réponse face à l'exposition du polluant. Il a été démontré que l'exposition parentale au diuron a des effets génotoxiques chez C. gigas au stade de naissain. Une variabilité phénotypique de trait d’ histoire de vie a été observée aussi pour ces naissains. Un autre effet possible des pesticides serait la modification de marques épigénétiques. Il est connu que les facteurs environnementaux telle que la pollution par des composés chimiques peuvent modifier l'épigénome et par conséquent le phénotype des individus et de leurs descendance en agissant au niveau trans-générationnel. Ces dernières observations nous permettent d’émettre l’hypothèse de l’implication de mécanismes épigénétiques suite à l’interaction avec des produits phytosanitaires. Ces mécanismes modifieraient le phénotype des huîtres au stade de naissains par l'exposition parental. Pour tester cette hypothèse nous avons étudié la méthylation globale de l'ADN (méthylome), qui est un de principal marques épigénétiques, et le transcriptome des naissains issus de géniteurs exposé au Diuron. Nous avons identifié des modifications du méthylome et du transcriptome qui ont un lien avec le phénotype de trait d'histoire de vie de ces naissains. Ces résultats démontreraient qu’une exposition indirecte ou parentale du diuron modifie la méthylation et l'expression de fonctions de gènes spécifiques, expliquant en partie la variabilité phénotypique observée. / The Pacific Oyster Crassostrea gigas is the most cultivated marine species in the world with a production superior to 4 millions of tons in 2010. In France, C. gigas is cultivated since the end of 1970s. However, this specie suffers from a syndrome of summer mortalities since the 1980s, with an amplification since 2008 affecting up to 100% of spats. This syndrome of mortality is a multifactorial phenomenon, based on the interaction of many factors: Environmental factors, genetic and physiologic features of the oysters, and the presence and virulence of pathogens. The Pacific Oyster C. gigas is an estuarine specie which is subjected to anthropogenic pressures such as pollution of the coastal environment. These events represent a potencial source of stress in oyster farm areas. However, the knowledge about the effects of pollutants such as pesticides on C. gigas remain fragmented. The herbicide application periods may coincide with the oyster breeding period, reason for which we consider that these chemicals could affect the next generation of oysters. Among pesticides, diuron is the most frequently detected on the French coast, with a maximum reported concentration of 0.78 µgL-1.The direct exposure to herbicides affects the transcriptome of oysters which is the first level of response to the exposure of pollutants. It was shown that parental exposure to diuron has genotoxic effects on C. gigas at the spat stage. A phenotypic variability of life history traits has also been observed for these spats. Another possible effect of pesticides would be the modification of epigenetic marks. It is known that environmental factors such as pollution by chemical compounds can alter the epigenome and consequently the phenotype of individuals and of their offspring acting at a transgenerational level. These last observations allow us to hypothesize the involvement of epigenetic mechanisms in response to interactions with herbicide products. These mechanisms could modify the phenotype of oysters spat state by parental exposure. To test this hypothesis we studied the genome-wide DNA methylation (methylome), which is a main epigenetic mark, and the transcriptome of the spat from diuron-exposed genitors. We identified methylome and transcriptome changes that are related to the phenotype of life history trait of these spats. These results show that an indirect or parental exposure to the diuron is able to modify the methylation and the expression of specific gene functions, partially explaining the phenotypic variability observed.
23

Identification de voies neuroendocriniennes du contrôle de la physiologie chez l'huître Crassostrea gigas par la caractérisation fonctionnelle de couples ligands/récepteurs / Identification of neuroendocrine pathways regulating physiological processes in the oyster Crassostrea gigas via the functional characterization of ligand / receptor couples

Schwartz, Julie 25 January 2019 (has links)
Les acteurs neuroendocriniens régulant la physiologie des Lophotrochozoaires, groupe frère des Ecdysozoaires parmi les Protostomiens, demeurent peu connus. Grâce à l’émergence récente de ressources génomiques, transcriptomiques et peptidomiques chez l’huître creuse Crassostrea gigas, l’étude des couples ligand(s)/récepteur(s) régulant les fonctions physiologiques est désormais facilitée. Ainsi, par une approche d’endocrinologie inverse consistant à éprouver l’activité d’un panel de ligands potentiels, plusieurs récepteurs couplés aux protéines G (RCPGs), jusqu’alors orphelins ont pu être caractérisés sur le plan fonctionnel. Trois voies de signalisation ont été étudiées : la voie de type cholécystokinine/sulfakinine (CCK/SK) la voie de type calcitonine (CT) et la voie de type dopamine (DA). Grâce à des tests fonctionnels, deux neuropeptides et deux récepteurs de type CCK/SK ont pu être caractérisés. Des tests d’activité biologique in vitro et des expériences de conditionnement alimentaire ont montré la potentielle implication de ces couples dans la régulation de la digestion et de la satiété chez l’huître. Par ailleurs, deux couples neuropeptide/récepteur de type CT ont été caractérisés montrant, à l’image de leurs homologues chez les vertébrés, leur possible rôle dans la régulation hydrique ou ionique. D’autre part, un récepteur activé de manière spécifique par la dopamine et la tyramine a été caractérisé. Ce système de signalisation semble être impliqué dans la médiation du stress et intervenir dans les processus régulateurs de la reproduction au niveau de la gonade. Ainsi, les différents résultats obtenus au cours de ces travaux ont permis d’identifier des couples ligands/récepteurs d’huître homologues de systèmes de signalisation présents chez les Ecdysozoaires et les vertébrés confirmant l’origine de ces systèmes neuroendocriniens depuis l’ancêtre commun des Bilatériens. Les résultats obtenus ont également permis de mieux comprendre comment l’huître intègre les paramètres du milieu et donc s’acclimate aux différentes contraintes environnementales. / The neuroendocrine regulators of the physiology of Lophotrochozoa, the sister clade of Ecdysozoa among Protostoma, remain poorly understood. Thanks to the recent emergence of genomic, transcriptomic and peptidomic resources in the Pacific oyster Crassostrea gigas, the functional characterization of ligand/receptor pairs regulating a diversity of physiological functions has been facilitated. Using a reverse endocrinology approach, a number of orphan G Protein-Coupled Receptors (GPCRs) have been functionally characterized. Three signalling systems have been studied in the oyster: The cholecystokinin/sulfakinin (CCK/SK), the calcitonin (CT) and the dopamine (DA) signalling systems. Two CCK/SK receptors and ligands have been characterized. In vitro bioassays and feeding conditions suggested the potential involvement of this signalling system in the regulation of digestion and satiety. Besides, two couples of CT-type peptides and receptors have been characterized showing, as for their vertebrate counterparts, their possible role in the regulation of water and ion balance. A receptor specifically activated by dopamine and by tyramine has also been characterized. This signalling system appeared to be implicated in the mediation of stress and to play a role in the regulatory processes of reproduction in the gonads. This study allowed the characterization in the oyster of ligand receptor pairs homolog to known signalling systems present in Ecdysozoa and vertebrates, thus confirming the origin of these neuroendocrine systems in the common ancestor of Bilateria. The results of this study also contributed to understand how the oyster integrates external parameters and adapts to various environmental constrains.
24

Is the laboratory growth of Pacific oyster spat, Crassostrea gigas, exposed to varying salinities, predictive of their growth in the estuary?

Brooks, Christopher 16 August 1999 (has links)
Results of this study suggest that laboratory growth of full-sib families of five month old Pacific oyster spat can be predictive of growth to market size at different grow-out sites. Seven to ten millimeter spat were selected from each of fifteen full-sib families and commercially available polyploids. Each family was split into two groups and exposed to either variable salinity (V.S., 3-30 ppt) or constant salinity (C.S., 30 ppt) laboratory conditions for five months, then planted at either an upriver or downriver subtidal site in the Yaquina estuary, Oregon. After six months of growth in the estuary, the rankings of the families based on average individual weights, specific growth rates (SGR), survival and yields were compared between laboratory and estuary sites. There was a significant effect of family, laboratory treatment and site upon final individual live weights of oysters in the estuary (P=0.0001). The rankings of families based on average individual laboratory weights were correlated with average individual estuary weights at the downriver site (C.S. oysters, P=0.010, V.S. oysters, P=0.005). Tetraploid oysters grew to heavier final estuary weights than either triploids or diploids, with individual C.S. tetraploids averaging 79.4 g live weight by fifteen months of age. Laboratory family rankings based on SGRs were negatively correlated with estuary rankings of family SGRs for all treatments (P<0.0001, Rho=-0.668). Rankings of families based on laboratory yields on day 60 were correlated with standardized estuary yield rankings for all treatments, except V.S. oysters planted downriver. Laboratory yields of families were also found to be predictive of estuary yields at an intertidally planted site in Sequim Bay, Washington, indicating the potential for predicting yields across a wide range of sites and culture methods (subtidal vs. intertidal). Oyster breeding programs may realize more efficient progress from the results of this study. If family yields at grow-out sites can be predicted from spat yields in the laboratory, poor and average families could be identified early at the spat stage, eliminating the need to expend resources to plant them out at test sites. / Graduation date: 2000
25

Clonagem, caracterização e análise filogenética das subunidades alfa e beta do hormônio folículo estimulante de Pirarucu (Arapaima gigas) visando sua síntese em células CHO / Cloning, characterization and phylogenetic analisys of the alpha and beta subunits of the follicle stimulating hormone of Pirarucu (Arapaima gigas) in view of its synthesis in cho cells

Roberto Feitosa de Carvalho 16 June 2014 (has links)
O Pirarucu (Arapaima gigas) é um peixe gigante da família Arapaimidae, nativo das bacias amazônicas que pode chegar a dois metros de comprimento e pesar mais de 200 Kg. Está presente no Equador, na Colômbia, no Peru, na Bolívia e no Brasil. Atualmente a espécie está ameaçada de extinção devido à pesca predatória e ao aumento da presença humana em seus viveiros naturais. No presente trabalho, os cDNAs da subunidade (ag-GTH&alpha;) e da subunidade &beta; do hormônio folículo estimulante de A. gigas (ag-FSH) foram isolados e clonados pela primeira vez, possibilitando uma melhor compreensão da diversidade e evolução desta glicoproteína em peixes e a futura síntese biotecnológica deste hormônio para fins reprodutivos e alimentícios. Tanto o cDNA do ag-GTH&alpha; quanto aquele do ag-FSH&beta; foram sintetizados pela reação de transcriptase reversa (RT) e pela reação em cadeia da polimerase (PCR) utilizando como molde RNA total proveniente das glândulas hipofisárias de A. gigas. O cDNA da subunidade ag-GTH&alpha; possui uma sequência codificadora (Open Reading Frame, ORF) de 348 pb, o que corresponde a uma proteína de 115 aminoácidos com um suposto peptídeo sinal de 24 aminoácidos e com um peptídeo maduro de 91 aminoácidos. Dez resíduos de cisteínas responsáveis pela formação de cinco pontes dissulfeto, dois sítios de N-glicosilação e três resíduos de prolinas apresentaram-se altamente conservados quando comparados com outras espécies de peixes. A comparação baseada em sequências de aminoácidos de GTH&alpha; de 38 espécies de peixes revelou alta identidade do A. gigas com membros das seguintes ordens: Acipenseriformes, Anguiliformes, Siluriformes e Cypriniformes (87,1-89,5%), e, a menor identidade com os Gadiformes e Cyprinodontiformes (55%). A identidade com a análoga sequência de GTH&alpha; de Homo sapiens foi de 67%. Para a subunidade ag-FSH&beta;, a ORF correspondente foi de 381 pb, produzindo uma proteína de 126 aminoácidos com um peptídeo sinal de 18 e um peptídeo maduro de 108 aminoácidos. Quando comparado com as sequências de Anguilla marmorata, Acipenser gueldenstaedtii e Homo sapiens, o peptídeo maduro de ag-FSH&beta; mostrou conter 12 resíduos de cisteínas responsáveis pela formação de seis pontes dissulfeto, duas prolinas e um sítio de glicosilação perfeitamente conservados, apresentando identidades de 63, 50 e 45% respectivamente em suas sequências de aminoácidos. As árvores filogenéticas construídas mostraram, em geral, que o A. gigas, da ordem dos Osteoglossiformes, se apresenta como grupo irmão dos Clupeocefala, enquanto os Elopomorpha (Anguiliformes) formam o grupo mais basal de todos os teleósteos aqui analisados. / Pirarucu (Arapaima gigas) is a giant fish of the Arapaimidae family native to the Amazon river basin, that can reach 3 meters in length, weighing up to 250 Kg. It is present in Equador, Colombia, Peru, Bolivia and Brazil. This species is in danger of disappearing due to exploitation by the fishing industry and increasing human presence in its natural habitat. In the present work the cDNAs of the gonadotropin -subunit (ag-GTH) and of follicle-stimulating hormone &beta; subunit (ag-FSH&beta;) were isolated and cloned for the first time. As a consequence, a better understanding of the diversity and evolution of this glycoprotein in fish and its future biotechnological synthesis for reproductive and alimentary purposes will be possible. Both cDNAs of ag-GTH&alpha; and ag-FSH&beta; have been synthesized via reverse transcriptase reaction (RT-PCR) and polymerase chain reaction (PCR) using as a template total RNA extracted from A. gigas pituitary glands. Ag-GTH&alpha;- subunit has a coding sequence (open reading frame, ORF) of 348 bp, corresponding to a 115 amino acid protein, with a putative signal peptide of 24 aminoacids and a mature peptide of 91 amino acids. Ten cysteine residues, responsible for the formation of five disulfide linkages, two N-glycosylation sites and three proline residues were found highly conserved when compared to other fish species. A comparison based on the amino acid sequence of the GTH&alpha;- subunit from 38 different species of fish showed high identity of A. gigas with members of the following orders: Acipenseriformes, Siluriformes and Cypriniformes (87.1-89.5%), while the lowest identity was found with Gadiformes and Cyprinodontiformes (55%). In comparison with the analogous sequence of Homo sapiens an identity of 67% was found. For the ag-FSH&beta; subunit an ORF of 381 bp, coding for a 126 amino acid protein, with a signal peptide of 18 and a mature peptide of 108 amino acids, was found. When compared with the Anguilla marmorata, Acipenser gueldenstaedtii and Homo sapiens, the mature peptide of ag-FSH&beta; showed the presence of the twelve cysteine residues responsible for the formation of six disulfide linkages, two proline residues and one glycosylation site, all of them perfectly conserved. The identity with the mentioned species were 63, 50 and 45% respectively. The obtained phylogenetic trees have shown, in general, that A. gigas of the order of Osteoglossiformes appears as sister group of Clupeocephala, while Elopomorpha (Anguilliformes) forms the most basal group of all analyzed teleosts.
26

Análise de parentesco em filhotes de pirarucu (Arapaima gigas Cuvier, 1817), utilizando marcadores microssatélites.

Almeida, Yane Santos 26 October 2006 (has links)
Submitted by Alisson Mota (alisson.davidbeckam@gmail.com) on 2015-07-15T20:46:06Z No. of bitstreams: 1 Dissertação - Yane Santos Almeida.pdf: 12026649 bytes, checksum: 336dd3f741f4d47da3ee54bbe3001d07 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-16T15:40:45Z (GMT) No. of bitstreams: 1 Dissertação - Yane Santos Almeida.pdf: 12026649 bytes, checksum: 336dd3f741f4d47da3ee54bbe3001d07 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-16T15:44:31Z (GMT) No. of bitstreams: 1 Dissertação - Yane Santos Almeida.pdf: 12026649 bytes, checksum: 336dd3f741f4d47da3ee54bbe3001d07 (MD5) / Made available in DSpace on 2015-07-16T15:44:31Z (GMT). No. of bitstreams: 1 Dissertação - Yane Santos Almeida.pdf: 12026649 bytes, checksum: 336dd3f741f4d47da3ee54bbe3001d07 (MD5) Previous issue date: 2006-10-26 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / Arapaima gigas, known in Brazil as pirarucu, is on of the most economically important species in the Amazon watershed. However there is scarce knowledge of some aspects of its biology, behavior and growing rates in any modality of intensive farming. Pirarucu presents a complex reproductive behavior, including formation of couples; nest building; and parental care by male, as observed by farmers and other authors. The present work aim to generate information about genetic kinship between nestling of pirarucu from captivity and semi-open areas (Santarém), by means of microsatellite markers. This technique is the most used molecular marker to reveal leveis or genetic relationships within and between group of brothers and dose relatives. Kinship analyses were carried out with nine (the most polymorphic) microsatellite developed for A. gigas. The genotypes were done in the automatic DNA sequencer MegaBace 1000 using the software Genetic Profiler v1.2. Allelic frequencies and expected and observed heterozigosity values were obtained in the software ARLEQUIN and GENETIX v. 4. Genotypes of all the nestling of two offspring were used to calculate the pairwise kinship relationships and kinship relationships using the software KINSHIP vl. 2, based on all loci. The reitionships categories were estimated in the sofiware ML-RELATE. Our results indicated that, on average, the captivity offspring presented a high estimative of relationship, varying from 0.48 in Itacoatiara 2 e Rio Preto da Eva, to 0.51 in Itacoatiara 1. In Santarém samples, the average values varied from 0,46 to 0,80 in STM G2 e STM G3, respectiveiy. The relationship categories matrixes show that the higher frequency observed in nestling is the category of non-related (U), both in captivity groups as semi-open areas groups. When we analyzed separately each sample, we find other level of kinship reiationships or kinship categories in the nestling. These results indicate that, despite the nestling are highly related, the hypotheses of an “extra maternity or paternity” of the pair of reiationship can not be ignored. These results demonstrate a reproductive strategy natural and effective to keep the genetie variability in the nestling of Arapaima gigas. / Arapaima gigas, conhecido no Brasil como pirarucu, é uma das espécies economicamente mais importantes da bacia Amazônica. No entanto, o conhecimento sobre alguns aspectos da biologia, comportamento e crescimento, em qualquer modalidade de criação intensiva, ainda é escasso. O pirarucu apresenta um comportamento reprodutivo complexo e durante esse período, observações de criadores e de outros autores afirmam que: ocorre a formação de casais, construção de ninhos e o cuidado parental da prole que é realizado pelo macho. O presente trabalho teve o intuito de fornecer informações sobre o parentesco genético, entre filhotes de pirarucu, provenientes de áreas de cativeiro e de área semi-aberta (Santarém), utilizando marcadores microssatélites. A técnica mencionada tem sido a ferramenta molecular mais utilizada pelos pesquisadores para revelar níveis de relacionamento genético dentro e entre grupos de irmãos e parentes mais próximos. As análises de parentesco foram feitas utilizando-se nove (os mais polimórficos) microssatélites desenvolvidos para A. gigas. As genotipagens foram realizadas no seqüenciador automático de DNA MegaBace 1000 utilizando-se o programa Genetic Profiler v1.2. As freqüências alélicas e os valores de heterozigosidade esperadas e observadas foram obtidos através do programa ARLEQUIN e GENETIX v. 4. Genótipos para todos os filhotes das duas ninhadas, foram usados para calcular os coeficientes de relacionamento dos pares e a relação de parentesco, usando o programa de computador KITNSHIP v1.2, baseado em todos os locos. As categorias de relacionamento foram estimadas usando o programa ML-RELATE. Nossos resultados indicaram que as ninhadas, das áreas de cativeiro apresentaram, em média, estimativas altas de relacionamento, variando de 0,48 em Itacoatiara 2 e Rio Preto da Eva a 0,51 em Itacoatiara 1. Nas amostras de Santarém, os valores médios encontrados variaram de 0,46 a 0,80 em STM G2 e STM G3, respectivamente. As matrizes das categorias de relacionamento, mostram que tanto nos grupos de cativeiro, como nos grupos de área semi-aberta, a maior freqüência observada nos filhotes é da categoria não-relacionados (U). Quando analisamos separadamente cada amostragem, percebemos outros níveis de relações de parentesco ou categorias de relacionamento nos filhotes. Esses resultados indicam que, apesar dos filhotes estarem altamente relacionados, a hipótese de uma “maternidade ou paternidade extra” aos pares do acasalamento, não pode ser ignorada. Tais resultados demonstram uma estratégia reprodutiva natural e efetiva, para a manutenção da variabilidade genética na prole de Arapaima gigas.
27

Larvicultura do pirarucu em sistema de bioflocos

Dantas, Naiara Silva Menezes, (92) 992409945 28 August 2018 (has links)
Submitted by Naiara Dantas (naiarasmd@hotmail.com) on 2018-09-27T17:44:44Z No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dantas, Naiara Silva Menezes, 2018. Larvicultura do pirarucu em sistema de bioflocos.pdf: 1218709 bytes, checksum: 213b02ee7990da341a78103dd76747b0 (MD5) CartaEncaminhamentoAutodepósito Pedro.pdf: 143442 bytes, checksum: 75844e2eba1a4950b63502ccdb712793 (MD5) ata.pdf: 181412 bytes, checksum: 1015e0dd0d3aecb8e98294006e80a524 (MD5) / Approved for entry into archive by PPGCAN Ciência Animal (ppgcan.ufam@gmail.com) on 2018-09-27T19:45:59Z (GMT) No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dantas, Naiara Silva Menezes, 2018. Larvicultura do pirarucu em sistema de bioflocos.pdf: 1218709 bytes, checksum: 213b02ee7990da341a78103dd76747b0 (MD5) CartaEncaminhamentoAutodepósito Pedro.pdf: 143442 bytes, checksum: 75844e2eba1a4950b63502ccdb712793 (MD5) ata.pdf: 181412 bytes, checksum: 1015e0dd0d3aecb8e98294006e80a524 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-09-27T20:33:38Z (GMT) No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dantas, Naiara Silva Menezes, 2018. Larvicultura do pirarucu em sistema de bioflocos.pdf: 1218709 bytes, checksum: 213b02ee7990da341a78103dd76747b0 (MD5) CartaEncaminhamentoAutodepósito Pedro.pdf: 143442 bytes, checksum: 75844e2eba1a4950b63502ccdb712793 (MD5) ata.pdf: 181412 bytes, checksum: 1015e0dd0d3aecb8e98294006e80a524 (MD5) / Made available in DSpace on 2018-09-27T20:33:38Z (GMT). No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dantas, Naiara Silva Menezes, 2018. Larvicultura do pirarucu em sistema de bioflocos.pdf: 1218709 bytes, checksum: 213b02ee7990da341a78103dd76747b0 (MD5) CartaEncaminhamentoAutodepósito Pedro.pdf: 143442 bytes, checksum: 75844e2eba1a4950b63502ccdb712793 (MD5) ata.pdf: 181412 bytes, checksum: 1015e0dd0d3aecb8e98294006e80a524 (MD5) Previous issue date: 2018-08-28 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / FAPEAM / Arapaima is considered the largest carnivorous species of Amazon and can reach up to 200 kg in the natural environment. Its high market value is due to its fast growth, the peculiar taste of its flesh and the possibilities of use of its byproducts. One of the main challenges of the Arapaima farming is to offer its early stages because there is a high rate of mortality during the larval phase. In this phase, the larvae are usually in the ponds together with the breeding fish, when they are susceptible to parasites, predators and lack of live food. As an alternative, the intensive larviculture allows the control of the environment, creating appropriate conditions for the larvae development. The biofloc technology (BFT) fits this possibility because it provides a better control of the quality of water and pathogens, and the biofloc could be an additional source of food. The objective of this work is to evaluate the performance of the Arapaima larvae reared in BFT. The experimental design was completely randomized with two treatments, a system with clear water (AC) as control and a system of biofloc (BFT), composed of five replication tanks. Arapaima larvae were (0.778 ± 0.02 g and 4.84 ± 0.11 cm) were housed in PVC tanks (20 L; 25 fish per tank). Initially and at the end of the experiment, water were collected and five fish from each treatment were euthanized for microbiological analyzes of the gastrointestinal tract. At the end of the experiment, the water of the BFT was filtered for determination of the proximate composition of the biofloc. There was no significant difference between the performance variables in both treatments; such result was attributed to the inadequate ingestion of food due to the high need of airing for the biofloc floating, causing stress and possibly altering the immunity of the larvae, making them susceptible to pathogenic bacteria; in addition to the elevated levels of nitrogenous compounds, due to the high excretion of the larvae, becoming toxic to the fish. The BFT presented the greatest diversity of bacteria, being identified the genus Aeromonas, Bacillus, Citrobacter, Enterobacter, Hafnia, Klebsiella, Morganella, Proteus, Pseudomonas, Salmonella, Serratia, Staphylococcus and Yersinia. The biofloc presented 41% of crude protein. Although BFT is an ecologically system for reducing water use and recycling effluents, adjustments are still needed, such as keeping the biofloc at low levels, so that its use is feasible for Arapaima larvicultura. / O pirarucu é considerado a maior espécie carnívora da Amazônia e pode atingir até 200 Kg no ambiente natural. Seu alto valor no mercado deve-se ao bom desempenho zootécnico, sabor peculiar da sua carne e possibilidades para o aproveitamento de seus subprodutos. Um dos maiores desafios da cadeia produtiva do pirarucu é a oferta de formas jovens, pois há um índice elevado de mortalidade durante a fase larval. Geralmente, as larvas ficam nos viveiros junto com os reprodutores, e estão susceptíveis à presença de parasitos, predadores e falta de alimento vivo. Como alternativa, a larvicultura intensiva permite o controle do ambiente criando condições adequadas para o desenvolvimento dos peixes. A tecnologia do BFT se enquadra nesta possibilidade, pois proporciona melhor controle da qualidade de água e patógenos, além do biofloco ser uma fonte adicional de alimento. O objetivo deste trabalho foi avaliar o desempenho zootécnico das larvas de pirarucu no BFT. O desenho experimental foi inteiramente casualizado com dois tratamentos, um sistema com água clara (AC), como controle e, um sistema com a tecnologia bioflocos, composto por cinco repetições (tanques de PVC). Foram selecionadas 250 larvas de pirarucu (0,778 ± 0,02 g e 4,84 ± 0,11 cm) e distribuídas em tanques de PVC (20 L; 25 peixes por tanque). Inicialmente e ao final do experimento, cinco peixes de cada tratamento foram eutanasiados para análises microbiológicas do trato gastrointestinal, assim como amostras de água dos sistemas. Ao final do experimento, a água do BFT foi filtrada para determinação da composição centesimal do floco. Não houve diferença significativa entre as variáveis de desempenho em ambos os tratamentos; atribui-se tal resultado à inadequada ingestão do alimento devido à forte aeração necessária para a flutuabilidade do floco, pois ocasionou estresse e possivelmente alterou a imunidade das larvas, tornando-as susceptíveis a bactérias patogênicas; além dos níveis elevados de compostos nitrogenados, devido à elevada excreção das larvas, tornando-se tóxicos para os peixes. O BFT apresentou a maior diversidade de bactérias dos gêneros Aeromonas, Bacillus, Citrobacter, Enterobacter, Hafnia, Klebsiella, Morganella, Proteus, Pseudomonas, Salmonella, Serratia, Staphylococcus e Yersinia. Os flocos microbianos apresentaram 41% de Proteína Bruta. Apesar do BFT ser vantajoso ecologicamente por reduzir o uso de águas e reciclar efluentes, ainda são necessários ajustes, como manter o biofloco em níveis baixos, para que seja viável sua utilização para a larvicultura. / Achei tranquilo / Primeiro trabalho com a espécie neste sistema
28

Écologie de la reproduction de l’huître creuse, Crassostrea gigas, sur les côtes atlantiques françaises : vers une explication de la variabilité du captage / Ecology of the reproduction of the cupped oyster on the french atlantic coasts

Bernard, Ismaël 08 June 2011 (has links)
L’activité de captage permet d’assurer l’approvisionnement en juvéniles d’huîtres creuses,C. gigas, pour de nombreux ostréiculteurs. Les professionnels du bassin d’Arcachon ont constaté une augmentation de la variabilité du nombre de naissains fixés depuis la fin des années 90. Cette thèse vise à identifier les sources d’une telle variabilité du recrutement de l’huître creuse. Cette question est abordée par une analyse originale de chacune des étapes du cycle de reproduction :un modèle DEB pour la gamétogenèse, la valvométrie pour l’émission des gamètes, des séries historiques de pêches de larves pour le stade larvaire et un modèle hydrodynamique pour la dispersion.Concernant la gamétogenèse, les résultats soulignent l’importance du paramètre de qualité du phytoplancton pour la description des variations de la fécondité. L’étude de l’émission des gamètes montre qu’elle intervient préférentiellement aux pleines mer, lors des marées de vives-eaux et pour des amplitudes thermiques quotidiennes importantes. Ces observations rendent l’émission des gamètes prévisible. Le captage à Arcachon dépend de la survie des cohortes larvaires, elle-même dépendante d’un effet climatique complexe structuré autour de la température de l’eau. Enfin, les bassins d’Arcachon et de Marennes-Olèron semblent soumis aux variations de l’apport en larves, avec une source extérieure aux zones de captage en Charente et une source interne déclinante à Arcachon. Ce déclin de l’apport en larves et l’effet climatique sont les deux sources supposées de la variabilité accrue du captage dans le bassin d’Arcachon. / Spat collecting supplies numerous oyster-farmers with young cupped oyster, C. gigas.Since the end of the nineties, professionals have noticed an increasing variability of the number of spat among years. This thesis aimed to identify the origin of the variability of oyster recruitment. This question is addressed by different methods for each step of the reproduction of oyster: a DEB model for gametogenesis, valvometry for spawning, cohort analysis for larvalstage and hydrodynamic models for dispersion.At the stage of the gametogenesis, variations of fecundity appear to be mainly influenced by phytoplankton quality. The study of spawning shows that it happens during high tides of springtides, leading to a spawning that is foreseeable. For Arcachon Bay, spat number depends on the survival of larval cohort that is in turn submitted to a complex climatic effect mainly based on sea temperature. Arcachon and Marennes-Oléron Bays seem also to depend on the variability of larval supply: the supply of larvae is provide by a source of larvae in the north of spat collecting areas for Charente and by an local source that seems to decrease for Arcachon. This decreaseof larval supply and the climate effect are the two suspected origins of the increased variabilityof spat collecting in Arcachon Bay.
29

Growth, condition, survival and feeding rate of the Pacific oyster (Crassostrea gigas Thunberg) cultured in three distinct South African environments

Pieterse, Aldi 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2013. / No abstract available.
30

Análise da variabilidade genética das populações de pirarucu (Arapaima gigas, SCHINZ 1822) dos principais tributários do rio Amazonas através do uso de marcadores microssatélites

Leão, Adam Souza de Alencar 18 August 2009 (has links)
Submitted by Dominick Jesus (dominickdejesus@hotmail.com) on 2016-02-15T17:53:16Z No. of bitstreams: 2 Adam Souza de Alencar Leão.pdf: 2611223 bytes, checksum: cd2daf2bf8565d02d484dba67f31b189 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-02-15T17:53:16Z (GMT). No. of bitstreams: 2 Adam Souza de Alencar Leão.pdf: 2611223 bytes, checksum: cd2daf2bf8565d02d484dba67f31b189 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2009-08-18 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The pirarucu (Arapaima gigas) is one of the largest freshwater fishes of the world; it can grow to up to 3 meters, and weight up to 200 kg. It is an economically important fish used as a traditional food source in the Amazon basin. It has suffered a long history of commercial exploitation, which has resulted in various populations with critically low levels of genetic variability. The current work is a population genetic study of this specie with the goal of estimating levels of genetic variability for the principal tributaries of the Amazon River, comparing them to those observed in the main channel of the Amazon River, analyzing if there has been a reduction of genetic diversity in the analyzed localities, and if Arapaima gigas is a genetically structured species. With this goal in mind, 11 microsatellite markers were used due to their high levels of polymorphism and those are sufficiently informative for this type of a study. Average heterozygosity calculated across all loci for each sampling locality varied from 0.32 in Araguaia River to 0.70 in Mamirauá. Considering only localities from the main channel of the Amazon River, observed heterozygosity was 0.45 in Iquitos and 0.70 in Mamirauá. Observed heterozygosities in the tributaries of the Amazon River ranged from 0.32 in the Araguaia River to 0.62 in the Tapajós River. The ANOVA results showed a heterogeneous pattern in the distribution of genetic diversity in Arapaima gigas among all sampled localities, and between localities from the main stream of the Amazon River and its tributaries. On average, however, higher average heterozygosities were observed in the main stream Amazon River compared with tributaries. This pattern could be explained by the main stream Amazon River may be a zone of contact for Arapaima from different regions which could be facilitated by the ebb and flow of várzea waters. AMOVA demonstrated that 76.46% of genetic variance is explained by within individual contrasts, while 20.28% is explained by among locality contrasts. The among locality contrast is consistent with low migration rates of this species. A Bayesian analysis shows that there is population structuring in the form of a gradient along the length of the Amazon basin; this analysis also shows that tributaries do not contain genetically differentiated populations with respect to the main stream of the Amazon River. The observed genetic structuring of Arapaima gigas allows us to divide the Amazon basin in three macro-regions that should be differentially managed due to their genetic particularities; these regions are western Amazon comprising the localities of Iquitos, Letícia, Eirunepé, Mamirauá, Tapauá, Lábrea, Manuel Urbano e Borba; central Amazon comprising the localities of Carauarí, Coarí, RDS Piagaçu-Purus, Manacapuru, Careiro da Várzea, Nhamundá, Santarém (São Miguel Island) and Jacaréacanga; and eastern Amazon and the Araguaia/Tocanins basin comprising the localities of Macapá, Mexiana, Marabá and Bananal Island (Araguaia River). However, the spatial autocorrelation analysis shows that across the length of its distribution, this species is connected by gene flow. We observed a signature of recent population reduction using the M value test in 11 localities of the 20 localities sampled for this study. The most drastic reductions were observed for samples collected in Mexiana Island and in the Araguaia River (Bananal Island). These results should be viewed as an important signal of genetic fragility of Arapaima gigas individuals from these localities. Based on the presented data, it is strongly recommended that one implements a differentiated management and conservation strategy for this species for the three macro-geographic regions of the Amazon basin identified through the genetic particularities of Arapaima gigas in each of these three regions. / O pirarucu (Arapaima gigas) é um dos maiores peixes de água doce do mundo, podendo crescer até 3 metros de comprimento e pesar até 200 quilos. É um peixe de grande importância econômica usado como fonte de alimento pela população tradicional na bacia Amazônica. É marcado por uma longa história de exploração comercial, o que reduziu a variabilidade genética de muitos grupos de indivíduos desta espécie. O presente trabalho reporta um estudo de genética de populações para o Arapaima gigas objetivando estimar níveis de variabilidade genética de espécimes coletados em 20 localidades ao longo da bacia Amazônica e Tocantins/Araguaia, investigar se há existência de estrutura genética e verificar se houve redução populacional. Para isso foram utilizados 11 marcadores microssatélites que devido ao seu elevado polimorfismo atendem às necessidades deste estudo. A heterozigosidade média observada sobre todos os locos para cada localidade amostrada variou de 0,32 para os espécimes coletados no rio Araguaia a 0,70 para para os espécimes coletados em Mamirauá. Considerando apenas localidades da calha principal do rio Amazonas, a heterozigosidade observada foi de 0,45 em Iquitos a 0,70 em Mamirauá. Enquanto que para os tributários da bacia Amazônica amostrados foi verificado 0,32 no rio Araguaia a 0,62, no rio Tapajós. Os resultados da análise de ANOVA, utilizada para testar se há diferenças significativas na distribuição da heterozigosidade observada em relação às localidades amostradas e em relação às amostras coletadas na calha e nos principais tributários da bacia Amazônica, mostraram um padrão heterogêneo na distribuição da variabilidade genética para a referida espécie, sendo que altos e baixos valores são distribuídos de maneira não uniforme entre as localidades amostradas para o presente estudo e foi encontrado um maior valor de variabilidade genética para as amostras coletadas na calha do que nos tributários amostrados. O fato de haver maior variabilidade genética nos indivíduos coletados na calha pode ser devido ao fato de a calha funcionar como um ponto de encontro de Arapaimas de várias localidades, com deslocamento favorecido pelas transgressões e introgressões das águas de várzea. Os resultados de AMOVA demonstram que os grupos analisados no presente estudo encontram-se moderadamente estruturados. Resultado condizente com os hábitos de baixa migração da referida espécie. Os resultados da análise Bayesiana mostram que há estrutura populacional na forma de gradiente ao longo da bacia amazônica, esses resultados também mostram que os rios tributários não comportam populações geneticamente diferenciadas em relação à calha principal. A estruturação genética encontrada para a espécie Arapaima gigas nos permite dividir a bacia Amazônica em três macroregiões que devem ser manejadas de maneira diferenciada devido às suas particularidades genéticas, essas regiões são Amazônia ocidental compreendendo as localidades Iquitos, Letícia, Eirunepé, Mamirauá, Tapauá, Lábrea, Manuel Urbano e Borba; Amazônia central compreendendo as localidades Carauarí, Coarí, RDS Piagaçu- Purus, Manacapuru, Careiro da Várzea, Nhamundá, Santarém (Ilha de São Miguel) e Jacaréacanga; e Amazônia oriental e bacia do Araguaia / Tocantins compreendendo as localidades de Macapá, Mexiana, Marabá e Ilha do Bananal (rio Araguaia). O teste de auto- correlação espacial mostrou que entre toda a amostragem deste estudo há fluxo gênico para a espécie Arapaima gigas. Foi observada redução populacional recente significativa através do teste de Mvalue para 11 das 20 localidades amostradas, sendo que reduções mais drásticas foram observadas para as amostras da Ilha de Mexiana na foz do rio Amazonas e Ilha do Bananal, no rio Araguaia. Esses resultados devem ser vistos como um aviso importante sobre a fragilidade genética dos grupos de Arapaima gigas dessas localidades. Desta forma, com base nos dados apresentados, é fortemente aconselhável que sejam implementados programas de manejo e conservação desta espécie de maneira diferenciada nas três macroregiões da bacia Amazônica, levando em conta as particularidades genéticas da espécie em cada região.

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