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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.
1

Profil et métabolisme des acides gras dans les tissus de la perche comme Perca fluviatilis L / Fatty acid composition and metabolism in tissues of Eurasian perch, Perca fluviatilis L

Peter, Magali 01 July 2008 (has links)
La perche commune, Perca fluviatilis L. est un poisson maigre (moins de 2% de lipides dans le filet) mais dont les teneurs en acides gras polyinsaturés de la famille n-3 (AGPIn-3) et principalement en acide docosahexaènoque (DHA) sont très élevées (40% des AG totaux). L’objectif de ce travail est d’étudier les facteurs qui influent sur le métabolisme lipidique chez la perche et qui assurent ces taux élevés de DHA. Les hypothèses testées qui permettraient d’expliquer les fortes teneurs en DHA sont une incorporation préférentielle de cet AG ainsi qu’une capacité, typique des poissons d’eau douce, à bioconvertir le 18:3n-3 présent dans l’alimentation en AGPI n-3 supérieur, EPA et DHA. Pour tester ces hypothèses nous avons mis en place trois expérimentations. Dans un premier temps, nous avons caractérisé les lipides des différents tissus impliqués dans le métabolisme lipidique en observant leurs teneurs en lipides totaux, neutres et polaires et leur composition en acides gras. Dans un deuxième temps nous avons déterminé et hiérarchisé les facteurs ayant un effet sur la teneur en lipides et la composition en AG en utilisant un plan d’expérience multifactorielle. Enfin, nous avons étudié plus particulièrement l’effet de la composition en acides gras de la source alimentaire sur la composition en AGPI n-3 des tissus, l’activité enzymatique et l’expression des gènes codant pour les enzymes impliquées dans la bioconversion des AG. Le génome de la perche n’étant pas séquencé pour l’instant, le premier travail a été de mettre au point les protocoles de dosage d’activité enzymatique et d’expression génique chez cette espèce. La qualité nutritionnelle de la perche a été vérifiée, avec la mise en évidence de taux élevés de DHA dans tous les tissus. Dans le muscle la teneur en lipides est stable. La teneur en AGPI est élevée (40-60% des AG totaux), avec des teneurs élevées en DHA (35-45% des AG totaux) qui est l’AG majoritaire dans ce tissu. La teneur en lipides du foie et du tissu adipeux est variable en fonction de l’aliment. Le tissu adipeux est le lieu de stockage de l’énergie, il contient entre 85-90% de lipides dont 30-50% sont sous forme mono-insaturée, principalement représentés par le 18:1n-9. Le foie a une composition en AG intermédiaire entre celle du muscle et celle du tissu adipeux, le DHA étant là aussi l’AG majoritaire. Nos résultats ont complété ceux de la littérature en donnant des informations sur la répartition et la teneur en lipides neutres et polaires des tissus (Muscle LN/LP= 50/50 ; Foie LN/LP= 60/40 ; Tissu adipeux : LN/LP= 90/10), ainsi que sur leur profil en acides gras (les lipides polaires sont composés majoritairement d’AGPI alors que les lipides neutres sont plus riches en acides gras saturés). Ils ont permis de mettre en évidence une spécificité du profil en acides gras en fonction du tissu ou du type de lipides. L’hypothèse de bioconversion des AGPI a été vérifiée puisque la delta 6 désaturase a été détectée dans le foie, l’intestin, le cerveau. De plus, son activité a été mise en évidence dans le foie. L’hypothèse d’incorporation préférentielle de certains acides gras a également été vérifiée, avec une incorporation préférentielle d’AGMI dans le tissu adipeux et d’AGPI dans le filet et le foie. Concernant l’effet des facteurs étudiés, nos résultats ont montré qu’il existe un déterminisme différent en fonction de l’acide gras.. La nature des lipides alimentaires est le facteur le plus important, il a un effet direct ou en interaction avec d’autres facteurs sur le profil en AG des tissus. Nos résultats ont montré que si l’alimentation est le facteur principal de variation, dans des conditions de croissance limitée, sur un poisson de taille commerciale, une teneur de 3% de DHA et de 2% d’EPA dans l’aliment est suffisante chez la perche pour obtenir une composition en acides gras du filet de bonne qualité pour le consommateur avec une bioconversion des AGPI n-3 limitée / Perca fluviatilis L. (Eurasian perch) is characterized by a low intramuscular amount of lipids (<2%) and a high poly-unsatured fatty acid (PUFA) content. Docosahexaenoic acid (DHA, 22:6n-3) is present in a high proportion (40% of total fatty acid). The aims of this work are twofold: first to analyse the factors that could influence the lipid metabolism of Perca fluviatilis L. and second to identify factors that could explain the elevated contents of DHA in this fish. Assumptions, which have been tested to explain the high concentration of DHA, are a selective incorporation of this fatty acid and the ability of this fish to transform 18:3n-3 present in the diet into higher PUFA n-3, EPA and DHA; typical capacity of freshwater fish (bioconversion assumption). Three experiments have been conducted to test these assumptions. First, we described lipid composition of the different tissues, which play a role in lipid metabolism, by distinguishing total, neutral and polar lipids. Second, we identified and classified the factors influencing the lipid content and fatty acid composition by using a multifactorial approach. Third, we analysed the effect of diet fatty acid composition on PUFA n-3 tissues composition, enzymatic activity and genes expression, which code for enzymes implicated in fatty acid bioconversion. As Perca fluviatilis L. genome is not sequenced for the moment, the first work was to construct experiments for dosing enzymatic activity and gene expression in this species. Concentration of DHA was elevated in all the tissues we analysed, showing the good nutritional quality of Perca fluviatilis L. In the fillet, lipid content was stable. PUFA content was high (40-60% of total fatty acid), with elevated contents in DHA (35-45% of total fatty acid), which was the main fatty acid of this tissue. Lipid content in the liver and the fat tissue was variable according to the type of food. Adipose tissue, that is the lipid storage tissue in this species, was composed of 85-90% of lipid, of which 30-50% are mono-unsatured fatty acids (MUFA), mainly 18:1n-9. Liver fatty acid composition presented characteristics in an intermediate position between fatty acid composition of the fillet and the adipose tissue, but DHA was still the most abundant fatty acid. Our results were in accordance with literature. They added informations on the distribution and the concentration in neutral and polar lipids (NL and PL) of the tissues we studied (fillet NL/PL=50/50; Liver: NL/PL=60/40; adipose tissue: NL/PL=90/10), and on their composition in fatty acid (polar lipids are mainly composed of PUFA whereas neutral lipids are richer in saturated fat acids). Our results showed that the profile in fat acid depended on the tissue and the type of lipids. Our assumption of the ability of Perca fluviatilis L. to transform PUFA was verified because we were able to detect delta 6 desaturase in the liver, intestine, and brain. Moreover, the activity of this enzyme was put in evidence in the liver. Our assumption of selective incorporation of some fatty acids was also verified, MUFA being preferentially absorbed in the adipose tissue and PUFA in the fillet and the liver. Regarding the effect of factors we studied, our results showed that a differential determinism existed according to the type of fatty acid. The nature of lipids contained in the diet was the most important factor. This factor could influence the profile of fatty acid in the tissues through a direct effect or in interaction with other factors. Although the diet is the main factor of variation, our results showed that under condition of limited growth and for a fish with a commercial size, a content of 3% of DHA and 2% of EPA in the diet was sufficient to obtain, in the fillet, a composition in fatty acids of good quality for consumers with a limited bioconversion of PUFA
2

Histoire évoutive et phylogéographie de la colonisation des eaux douces par une espèce d'origine marine, la blennie fluviatile (Salaria fluviatilis) / Evolutionary history and phylogeography of the freshwater colonisation by a species with a marine origin, the freshwater blenny (Salaria fluviatilis)

Laporte, Martin 14 December 2012 (has links)
La blennie fluviatile (Salaria fluviatilis) est une espèce qui a colonisé l'environnement dulcicole à partir d'un ancêtre marin et habite actuellement lacs et rivières situés autour de la Méditerranée. Comment un tel changement d'environnement peut avoir affecté la structure génétique et le phénotype de cette espèce ? C'est autour de cette question centrale que s'articulent les deux principaux volets de cette thèse. Le premier s'intéresse aux conséquences d'évènements géologiques historiques, affectant la structure génétique de S. fluviatilis. Nous y verrons, entre autres, qu'à l'intérieur du bassin occidental de la Méditerranée, les localisations les plus nordiques ont été colonisées à partir de deux refuges glaciaires. Le deuxième volet est centré sur l'adaptation et l'acclimatation que nécessite un tel changement d'environnement. Il y sera révélé que les réponses de la forme du corps et la longueur des nageoires face à la vitesse du courant sont contrôlées par un déterminisme environnemental chez la blennie fluviatile. Ensemble, ces deux volets permettent de mieux comprendre les processus derrière la différenciation des populations dans un contexte de colonisation d'un nouvel environnement. / The freshwater blenny (Salaria fluviatilis) colonised the freshwater environment from a marine ancestor and now inhabits lakes and rivers around the Mediterranean Sea. How this important environmental change affected the genetic structure and the phenotype of this species ? It is around this central question that two major axes will be developed in this thesis. The first axis focus on the consequences of historical geologic events that affected the genetic structure of S. fluviatilis. It will be show that the northern locations of the Occidental basin of the Mediterranean sea were colonised from two different glacial refuges. The second axis focus on the adaptation and acclimation required to colonise a new environment. It will be show that the reponses of body shape and fins length of S. fluviatilis to water velocity are controlled by an environmental determinism. Together, these two axes will allow for a better understanding of populations differentiation process following the colonisation of a new environment.
3

Caracterização das emissões sonoras de Sotalia fluviatilis (Gervais, 1853) (Cetacea, Delphinidae) durante o comportamento alimentar em duas praias do estuário de Cananéia, São Paulo. / Sotalia fluviatilis (Gervais, 1853) sound emissions characterization e during feeding behaviour in two beaches in Cananéia estuary, São Paulo.

Pivari, Daniela 21 December 2004 (has links)
O estudo aqui apresentado teve dois objetivos: a descrição das emissões sonoras de S. fluviatilis e a classificação dos assobios analisados. Durante os meses de agosto e dezembro de 2002, foram gravadas emissões sonoras de indivíduos solitários e grupos de 2 a 10 animais que se aproximavam das praias do Pereirinha (Ilha do Cardoso) e da Ponta da Trincheira (Ilha Comprida) no complexo estuarino-lagunar de Cananéia, São Paulo para se alimentar. Para tal utilizou-se um hidrofone (HTI SSQ 94) acoplado a um gravador profissional analógico (SONY TCM 5000ev). Em cerca de 22h de gravações foram reportados 3.188 assobios (74,5%), 689 seqüências de clicks de ecolocalização (16%) e 406 sons pulsantes explosivos (9,5%), totalizando 4.283 emissões sonoras. Isto significa 0,93 emissões/minuto/indivíduo. Apenas as emissões de clara visualização previamente classificadas e abaixo de 20kHz de freqüência foram analisadas (61%). Os assobios foram classificados de duas formas, primeiramente pela técnica de observação humana e em um segundo momento através da aplicação de análise multivariada. Pelo método de observação humana 1.592 assobios foram classificados qualitativamente em 5 categorias de acordo com a forma física do contorno dado pelo número de pontos de inflexão apresentados. Foram encontrados assobios de 0 a 4 pontos de inflexão. A maior parte (89%) não apresentou pontos de inflexão e os assobios ascendentes foram os mais representativos (87%). Foram descritos apenas 213 (13,3%) assobios com harmônicos. A média de tempo de duração dos 1.592 assobios analisados foi de 0,23s (variação entre 0,04 e 0,64s). Já a variação de freqüência dos assobios encontrados neste trabalho esteve entre 1,01 e 19,98kHz. A média de modulação de freqüência encontrada para os indivíduos gravados em Cananéia foi de 7,22kHz. Foram encontradas variações quando se comparou este trabalho com outros estudos desenvolvidos com S. fluviatilis, mas isso se deve principalmente à utilização de diferentes métodos e equipamentos de gravação e análise de dados. Além disso, diferenças de hábitats, do contexto ecológico e comportamental entre os ecótipos fluvial e marinho devem ser levadas em consideração. Os resultados da análise multivariada aplicada para os 1.592 assobios de S. fluviatilis foram diferentes dos resultados encontrados pela a técnica de observação visual baseada no número de inflexões de cada assobio (análise univariada). A técnica multivariada associa todos os parâmetros acústicos mensurados e, a partir dessas associações, forma os grupos de assobios. Os 4 grupos apresentados pela técnica multivariada mostraram assobios com variados números de pontos de inflexões. São poucos os trabalhos que classificam os assobios de odontocetos de acordo com análise multivariada. A descrição qualitativa e quantitativa de assobios dos golfinhos faz-se necessária para futuras comparações entre populações de diferentes regiões geográficas ao longo da distribuição das espécies. Tais estudos reportam importantes relações ecológicas das populações estudadas e podem contribuir para os esforços de preservação das mesmas. / This study had two objectives: to describe the sound emissions of Sotalia fluviatilis and to classify the analyzed whistles. During August and December, 2002, whistle emissions were recorded from solitary individuals and groups of 2 to 10 individuals that, in order to capture preys, approached Pereirinha (Ilha do Cardoso) and Ponta da Trincheira (Ilha Comprida) beaches in Cananéia estuarine complex, São Paulo. A hydrophone (HTI SSQ 94), connected to a professional analog audio tape recorder (SONY TCM 5000ev) was used to capture the emissions. In 22 hours of acoustic data, 3.188 whistles (74,5%), 689 echolocation click sequences (16%) and 406 burst pulses (9,5%) were reported; totalling 4.283 sound emissions. This represents 0,93 emissions/minute/individual. Only the emissions with clear visualization and up to 20kHz were analyzed (61%). The whistles were classified in two ways: by human observation technique and through the multivariate analysis. Using human observation, 1.592 whistles were quantitatively classified in 5 categories, according to the physical shape of the contour resulting from the number of inflection points presented in the whistle. Whistles with up to 4 inflection points were found. Most of the whistles (89%) did not show inflection points; moreover, there were considerably more whistles with rising frequency. (87%). Only 213 (13,3%) whistles had harmonics. The average duration of the 1.592 whistles was 0,23s (but varied between 0,04 and 0,64s). The frequency modulation of the whistles varied between 1,01 and 19,98 (mean = 7,22kHz). Variations were found when compared to other studies carried out on S. fluviatilis; nevertheless, this occurred due to differences in methodology, recorder equipment and data analysis. Furthermore, varieties of habitats and the ecological and behavioral context between freshwater and marine ecotypes of S. fluviatilis must be considered. The results of the multivariate analysis, applied to the 1.592 whistles, were very different to the results of the human observation technique (univariate method). The multivariate analysis links all measured acoustics; forming whistle groups. Four groups were formed by this method; they showed whistles with varying numbers of inflection points. There are few studies that classify whistles of odontocetes according to multivariate analysis. This kind of study is important to comparisons between different populations. The qualitative and quantitative descriptions of the whistles are necessary for future comparisons among populations from different geographic regions along the species distribuition. This study reported important ecological relationships and can contribute to the efforts of preservation.
4

Estimativa populacional de folículos pré-antrais in situ de Sotalia fluviatilis (Cetacea, Delphinidae) / In situ analysis of preantral follicle populations in ovaries of the tucuxi dolphin sotalia fluviatilis (Cetacea, delphinidae)

Cavallante, Andréa Pighinelli January 2000 (has links)
CAVALLANTE, Andréa Pighinelli. Estimativa populacional de folículos pré-antrais in situ de Sotalia fluviatilis (Cetacea, Delphinidae). 2000. 67 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2000 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T11:44:33Z No. of bitstreams: 1 2000_dis_apcavallante.pdf: 777240 bytes, checksum: 39a347ed2388e4b8a3cbc5c7aa377fe0 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-11T11:45:08Z (GMT) No. of bitstreams: 1 2000_dis_apcavallante.pdf: 777240 bytes, checksum: 39a347ed2388e4b8a3cbc5c7aa377fe0 (MD5) / Made available in DSpace on 2016-07-11T11:45:08Z (GMT). No. of bitstreams: 1 2000_dis_apcavallante.pdf: 777240 bytes, checksum: 39a347ed2388e4b8a3cbc5c7aa377fe0 (MD5) Previous issue date: 2000 / Tucuxi, Sotalia fluviatilis, a coastal cetacean species threatened by artisanal fishing, needs a reproductive biology study in order to manage and preserve the populations subject to mortality for antropic action. A in situ of the preantral follicles allows a better understanding of the preantral phase of the folliculogenesis, little known in cetaceans and totally unknown in S. fluviatilis. Quantitative analysis of the preantral follicle was made in ovarian of S. fluviatilis recovered on the Ceara coast between 1997-1999. The age of the studied sample varied from 0 to 23 years, being sexual maturation above 6 years. The population preantral follicular analysed, was completely degenerate, possibly because of “pos-morten” time. Even so, significant difference were observed among sexual maturation stage, whwere immature animals showed na averege of 1.162.460 follicles, while in matures animals the averege was 66.270 follicles. Due to anatomic position of the ovarian, it was observed that the left ovarian had a higher number of follicles when compared to the right one. This difference was significant only for immature animals. There wasn’t a significant difference related to weight of right and left ovarian of mature and imature sample. Number of follicles showed a negative relation with age and weight of the ovarian, although weight had a positive relation with age. These results indicate that the population follicular fo S. fluviatilis may be affected by many factors such as: reproductive stage, age, ovarian weight and anatomical position of the ovary. Quantitative data of the foliculogenisis described can be used as a parameter for future studies in vitro or in vivo of the folliculogenisis of S. fluviatilis. From this, new information about preantral follicles of S. fluviatilis can be acquired, leading to new reserch to explain the folliculogenese of preantral follicles phase of the species, contributing to a better utilization of oociterio potencial. / O boto cinza, Sotalia fluviatilis, é uma espécie de cetáceo costeira ameaçada pela pesca artesanal, sendo necessário um estudo da biologia reprodutiva, para a administração e conservação das populações que estão sujeitas à mortalidade por ação antrópica. O estudo de folículos pré-antrais in situ permite uma melhor compreensão da fase pré-antral da foliculogênese, pouco conhecida nos cetáceos em geral, e totalmente desconhecida em S. fluviatilis. A análise quantitativa de folículos pré-antrais foi realizada enm ovários de S. fluviatilis recuperados na costa do Ceará entre 1997-1999. A idade dos exemplares em estudo variou de 0 a 23 anos, com idade de maturação sexual acima de 6 anos. A população folicular pré-antral analisada, apresentou-se totalmente degenerada, possivelmente em decorrência do tempo “pós-mortem”. Ainda assim, foram observadas diferenças significativas entre os estágios de maturação sexual, onde animais imaturos apresentaram uma média de 1.162.460 folículos, enquanto os exemplares maturos apresentaram em média 66.270 folículos. Em relação a posição anatômica do ovário foi observado que, em média, o ovário esquerdo apresentou um número mais elevado de folículos quando comparado ao lado direito. Essa diferença foi significativa somente para animais imaturos. Não houve uma diferença significativa com relação ao peso do ovário direito e esquerdo dos exemplares imaturos e maturos. O número de folículos apresentou uma relação uma relação negativa com a idade e peso do ovário, embora o peso tenha apresentado uma relação positiva com a idade. Tais resultados mostraram que a população folicular de S. fluviatillis pode ser afetada por diversos fatores, entre eles estágio reprodutivo, idade, peso ovariano e posição anatômica do ovário. Os dados quantitativos da foliculogênese descrito neste trabalho poderão servir como parâmetro para futuros estudos in vivo ou in vitro da foliculogênese em S. fluviatilis. Desta forma, novas informações acerca dos folículos pré-antrais de S. fluviatilis poderão ser obtidos, gerando oportunidade para a realização de novas pesquisas, visando a elucidação da foliculogênese da fase pré-antral na espécie, o que contribuirá no futuro para um melhor aproveitamento do seu potencial oocitário.
5

Composição e dinâmica da família Chironomidae em dois períodos hidrológicos distintos, durante o ciclo fenológico de Mayaca fluviatilis Aublet, 1775.

Escarpinati, Suzana Cunha 29 August 2006 (has links)
Made available in DSpace on 2016-06-02T19:31:36Z (GMT). No. of bitstreams: 1 DissSCE.pdf: 723485 bytes, checksum: 1757119ef02fa2dba80ba1297f9fd16b (MD5) Previous issue date: 2006-08-29 / The studied lake (Lagoa Mayaca) is located in a preservation area at the campus of the Universidade Federal de São Carlos. With the aim of analyzing the dynamic and the taxonomic composition of the Chironomidae, samples were taken through a transversal transect in two different periods (dry and wet season), comprehending the phenological cycle of Mayaca fluviatilis Aublet, 1775. From a total of 27 Chironomidae taxa, it was verified that the most abundant taxa in the dry season were: Cladopelma, Caladomyia sp1, Caladomyia riotarumensis, Djalmabatista pulcher, Ablablesmyia (Karelia), Tanytarsus rhabdomantis e Labrundinia. On the other hand, in the wet season the most representative were: Polypedilum (Asheum), Chironomus, Goeldichironomus, Endotribelos, Tanytarsus rhabdomantis, Caladomyia friederi, Ablablesmyia (Karelia), Labrundinia e Cricotopus. The greater taxonomic richness and number of specimens were registered in the sampled sites where Mayaca fluviatilis was present, indicating that the presence of this macrophyte was very important for structuring the studied community. / A lagoa estudada (Lagoa Mayaca) situa-se em uma área de preservação, dentro do campus da Universidade Federal de São Carlos. Com o objetivo de analisar a composição e a dinâmica taxonômica de Chironomidae, as coletas foram realizadas ao longo de um transecto transversal, em duas épocas distintas (estação de seca e de chuva), compreendendo o ciclo fenológico de Mayaca fluviatilis Aublet, 1775. Do total de 27 táxons de Chironomidae identificados, constatou-se que numericamente os táxons mais representativos para o período de estiagem foram: Cladopelma, Caladomyia sp1, Caladomyia riotarumensis, Djalmabatista pulcher, Ablablesmyia (Karelia), Tanytarsus rhabdomantis e Labrundinia. Já no período de chuva destacaram-se Polypedilum (Asheum), Chironomus, Goeldichironomus, Endotribelos, Tanytarsus rhabdomantis, Caladomyia friederi, Ablablesmyia (Karelia), Labrundinia e Cricotopus. A maior riqueza taxonômica e número de exemplares foram registrados nos pontos amostrais com presença de Mayaca fluviatilis, indicando que a presença desta macrófita foi de fundamental importância na estruturação da comunidade de larvas de Chironomidae estudada.
6

Caracterização das emissões sonoras de Sotalia fluviatilis (Gervais, 1853) (Cetacea, Delphinidae) durante o comportamento alimentar em duas praias do estuário de Cananéia, São Paulo. / Sotalia fluviatilis (Gervais, 1853) sound emissions characterization e during feeding behaviour in two beaches in Cananéia estuary, São Paulo.

Daniela Pivari 21 December 2004 (has links)
O estudo aqui apresentado teve dois objetivos: a descrição das emissões sonoras de S. fluviatilis e a classificação dos assobios analisados. Durante os meses de agosto e dezembro de 2002, foram gravadas emissões sonoras de indivíduos solitários e grupos de 2 a 10 animais que se aproximavam das praias do Pereirinha (Ilha do Cardoso) e da Ponta da Trincheira (Ilha Comprida) no complexo estuarino-lagunar de Cananéia, São Paulo para se alimentar. Para tal utilizou-se um hidrofone (HTI SSQ 94) acoplado a um gravador profissional analógico (SONY TCM 5000ev). Em cerca de 22h de gravações foram reportados 3.188 assobios (74,5%), 689 seqüências de clicks de ecolocalização (16%) e 406 sons pulsantes explosivos (9,5%), totalizando 4.283 emissões sonoras. Isto significa 0,93 emissões/minuto/indivíduo. Apenas as emissões de clara visualização previamente classificadas e abaixo de 20kHz de freqüência foram analisadas (61%). Os assobios foram classificados de duas formas, primeiramente pela técnica de observação humana e em um segundo momento através da aplicação de análise multivariada. Pelo método de observação humana 1.592 assobios foram classificados qualitativamente em 5 categorias de acordo com a forma física do contorno dado pelo número de pontos de inflexão apresentados. Foram encontrados assobios de 0 a 4 pontos de inflexão. A maior parte (89%) não apresentou pontos de inflexão e os assobios ascendentes foram os mais representativos (87%). Foram descritos apenas 213 (13,3%) assobios com harmônicos. A média de tempo de duração dos 1.592 assobios analisados foi de 0,23s (variação entre 0,04 e 0,64s). Já a variação de freqüência dos assobios encontrados neste trabalho esteve entre 1,01 e 19,98kHz. A média de modulação de freqüência encontrada para os indivíduos gravados em Cananéia foi de 7,22kHz. Foram encontradas variações quando se comparou este trabalho com outros estudos desenvolvidos com S. fluviatilis, mas isso se deve principalmente à utilização de diferentes métodos e equipamentos de gravação e análise de dados. Além disso, diferenças de hábitats, do contexto ecológico e comportamental entre os ecótipos fluvial e marinho devem ser levadas em consideração. Os resultados da análise multivariada aplicada para os 1.592 assobios de S. fluviatilis foram diferentes dos resultados encontrados pela a técnica de observação visual baseada no número de inflexões de cada assobio (análise univariada). A técnica multivariada associa todos os parâmetros acústicos mensurados e, a partir dessas associações, forma os grupos de assobios. Os 4 grupos apresentados pela técnica multivariada mostraram assobios com variados números de pontos de inflexões. São poucos os trabalhos que classificam os assobios de odontocetos de acordo com análise multivariada. A descrição qualitativa e quantitativa de assobios dos golfinhos faz-se necessária para futuras comparações entre populações de diferentes regiões geográficas ao longo da distribuição das espécies. Tais estudos reportam importantes relações ecológicas das populações estudadas e podem contribuir para os esforços de preservação das mesmas. / This study had two objectives: to describe the sound emissions of Sotalia fluviatilis and to classify the analyzed whistles. During August and December, 2002, whistle emissions were recorded from solitary individuals and groups of 2 to 10 individuals that, in order to capture preys, approached Pereirinha (Ilha do Cardoso) and Ponta da Trincheira (Ilha Comprida) beaches in Cananéia estuarine complex, São Paulo. A hydrophone (HTI SSQ 94), connected to a professional analog audio tape recorder (SONY TCM 5000ev) was used to capture the emissions. In 22 hours of acoustic data, 3.188 whistles (74,5%), 689 echolocation click sequences (16%) and 406 burst pulses (9,5%) were reported; totalling 4.283 sound emissions. This represents 0,93 emissions/minute/individual. Only the emissions with clear visualization and up to 20kHz were analyzed (61%). The whistles were classified in two ways: by human observation technique and through the multivariate analysis. Using human observation, 1.592 whistles were quantitatively classified in 5 categories, according to the physical shape of the contour resulting from the number of inflection points presented in the whistle. Whistles with up to 4 inflection points were found. Most of the whistles (89%) did not show inflection points; moreover, there were considerably more whistles with rising frequency. (87%). Only 213 (13,3%) whistles had harmonics. The average duration of the 1.592 whistles was 0,23s (but varied between 0,04 and 0,64s). The frequency modulation of the whistles varied between 1,01 and 19,98 (mean = 7,22kHz). Variations were found when compared to other studies carried out on S. fluviatilis; nevertheless, this occurred due to differences in methodology, recorder equipment and data analysis. Furthermore, varieties of habitats and the ecological and behavioral context between freshwater and marine ecotypes of S. fluviatilis must be considered. The results of the multivariate analysis, applied to the 1.592 whistles, were very different to the results of the human observation technique (univariate method). The multivariate analysis links all measured acoustics; forming whistle groups. Four groups were formed by this method; they showed whistles with varying numbers of inflection points. There are few studies that classify whistles of odontocetes according to multivariate analysis. This kind of study is important to comparisons between different populations. The qualitative and quantitative descriptions of the whistles are necessary for future comparisons among populations from different geographic regions along the species distribuition. This study reported important ecological relationships and can contribute to the efforts of preservation.
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Estimativa populacional de folÃculos prÃ-antrais in situ de Sotalia fluviatilis (Cetacea, Delphinidae) / In situ analysis of preantral follicle populations in ovaries of the tucuxi dolphin sotalia fluviatilis (Cetacea, delphinidae)

AndrÃa Pighinelli Cavallante 09 November 2000 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / O boto cinza, Sotalia fluviatilis, à uma espÃcie de cetÃceo costeira ameaÃada pela pesca artesanal, sendo necessÃrio um estudo da biologia reprodutiva, para a administraÃÃo e conservaÃÃo das populaÃÃes que estÃo sujeitas à mortalidade por aÃÃo antrÃpica. O estudo de folÃculos prÃ-antrais in situ permite uma melhor compreensÃo da fase prÃ-antral da foliculogÃnese, pouco conhecida nos cetÃceos em geral, e totalmente desconhecida em S. fluviatilis. A anÃlise quantitativa de folÃculos prÃ-antrais foi realizada enm ovÃrios de S. fluviatilis recuperados na costa do Cearà entre 1997-1999. A idade dos exemplares em estudo variou de 0 a 23 anos, com idade de maturaÃÃo sexual acima de 6 anos. A populaÃÃo folicular prÃ-antral analisada, apresentou-se totalmente degenerada, possivelmente em decorrÃncia do tempo âpÃs-mortemâ. Ainda assim, foram observadas diferenÃas significativas entre os estÃgios de maturaÃÃo sexual, onde animais imaturos apresentaram uma mÃdia de 1.162.460 folÃculos, enquanto os exemplares maturos apresentaram em mÃdia 66.270 folÃculos. Em relaÃÃo a posiÃÃo anatÃmica do ovÃrio foi observado que, em mÃdia, o ovÃrio esquerdo apresentou um nÃmero mais elevado de folÃculos quando comparado ao lado direito. Essa diferenÃa foi significativa somente para animais imaturos. NÃo houve uma diferenÃa significativa com relaÃÃo ao peso do ovÃrio direito e esquerdo dos exemplares imaturos e maturos. O nÃmero de folÃculos apresentou uma relaÃÃo uma relaÃÃo negativa com a idade e peso do ovÃrio, embora o peso tenha apresentado uma relaÃÃo positiva com a idade. Tais resultados mostraram que a populaÃÃo folicular de S. fluviatillis pode ser afetada por diversos fatores, entre eles estÃgio reprodutivo, idade, peso ovariano e posiÃÃo anatÃmica do ovÃrio. Os dados quantitativos da foliculogÃnese descrito neste trabalho poderÃo servir como parÃmetro para futuros estudos in vivo ou in vitro da foliculogÃnese em S. fluviatilis. Desta forma, novas informaÃÃes acerca dos folÃculos prÃ-antrais de S. fluviatilis poderÃo ser obtidos, gerando oportunidade para a realizaÃÃo de novas pesquisas, visando a elucidaÃÃo da foliculogÃnese da fase prÃ-antral na espÃcie, o que contribuirà no futuro para um melhor aproveitamento do seu potencial oocitÃrio. / Tucuxi, Sotalia fluviatilis, a coastal cetacean species threatened by artisanal fishing, needs a reproductive biology study in order to manage and preserve the populations subject to mortality for antropic action. A in situ of the preantral follicles allows a better understanding of the preantral phase of the folliculogenesis, little known in cetaceans and totally unknown in S. fluviatilis. Quantitative analysis of the preantral follicle was made in ovarian of S. fluviatilis recovered on the Ceara coast between 1997-1999. The age of the studied sample varied from 0 to 23 years, being sexual maturation above 6 years. The population preantral follicular analysed, was completely degenerate, possibly because of âpos-mortenâ time. Even so, significant difference were observed among sexual maturation stage, whwere immature animals showed na averege of 1.162.460 follicles, while in matures animals the averege was 66.270 follicles. Due to anatomic position of the ovarian, it was observed that the left ovarian had a higher number of follicles when compared to the right one. This difference was significant only for immature animals. There wasnât a significant difference related to weight of right and left ovarian of mature and imature sample. Number of follicles showed a negative relation with age and weight of the ovarian, although weight had a positive relation with age. These results indicate that the population follicular fo S. fluviatilis may be affected by many factors such as: reproductive stage, age, ovarian weight and anatomical position of the ovary. Quantitative data of the foliculogenisis described can be used as a parameter for future studies in vitro or in vivo of the folliculogenisis of S. fluviatilis. From this, new information about preantral follicles of S. fluviatilis can be acquired, leading to new reserch to explain the folliculogenese of preantral follicles phase of the species, contributing to a better utilization of oociterio potencial.
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Růst, genetické a morfologické charakteristiky různých populací okouna říčního (Perca fluviatilis) v intenzivní akvakultuře

GEBAUER, Tatyana January 2019 (has links)
Zootechnical and behavioural traits can vary substantially among wild allopatric European perch populations. Choosing wild European perch population(s) showing higher growth rate, lower cannibalism and size heterogeneity with specific behavioural traits such as low aggressive interaction rate and homogeneous spatial distribution in rearing units are crucial for the establishment of the European perch broodstock and subsequent selective breeding programs. Therefore, knowledge of the zootechnical and behavioural traits relative to geographic origin supported by genetic analyses may ultimately help to overcome current challenges and bottlenecks of European perch aquaculture. Population differences in zootechnical and behavioural traits can be shaped by genetic differentiation, phenotypic plasticity, or by their combination. However, it is not clear whether the inter-population differences are genetically- or environmentally-induced. Therefore, we explored the zootechnical traits of geographically different European perch populations at larval- (two Finish, two Polish, two Slovakian, one Czech; Chapter II) and juvenile-stages (Polish, Czech, Slovakian; Chapter III) in the same standardized conditions reducing the environmental effect. Additionally, we provided a genetic-based assessment on four mitochondrial markers: cytochrome b, D-loop of control region, 16S rRNA, and cytochrome oxidase I (Chapters II, III). In Chapter IV, we observed behavioural traits of larvae and juveniles from two Finish and one French populations. According to obtained results, zootechnical and behavioural traits differed among allopatric populations of European perch. Moreover, the differences in zootechnical traits were mainly observed between most genetically differentiated populations (both Finish in Chapter II, and Polish in Chapter III). This could suggest a genetic basis of the observed growth differentiation and, consequently, a potential heritability of this pattern. Additionally, higher growth rate of northern populations could be partly attributed to behavioural traits as we found more cohesive and homogenous group structure in both Finish compared to French populations which, on the other hand, showed higher aggressive interactions. However, European perch larvae and juveniles from genetically lower- or un-differentiated populations (i.e. Polish, Slovakian and Czech in Chapter II and Slovakian and Czech in Chapter III) showed variations in zootechnical traits as well. The variation could be a consequence of different food intake, health status, pre-collection environment, transgenerational effect and usage of conservative mitochondrial markers, i.e. the lack of genetic differentiation among some populations should be further assessed by higher resolution analyses (e.g. microsatellites). Further studies are needed to assess the importance of these factors in geographic differentiation of aquaculture performance.
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Molecular markers of ecotoxicological interest in the rainbowfish Melanotaenia fluviatilis

Ponza, Pattareeya, pattareeya.pon@biotec.or.th January 2007 (has links)
The Crimson-spotted rainbowfish (Melanotaenia fluviatilis) from the Murray-Darling basin of Australia is a common indicator species in Australian ecotoxicology. Biochemical changes have been investigated in this species, but not molecular markers of ecotoxicological interest. In this study genes of M. fluviatilis were isolated using a cDNA library and sequences analysed. Of 345 randomly selected clones, 94 shared similarity with 26 different genes in other organisms in public databases. Amongst these, reproductive genes coding for vitellogenin, retinol binding protein, sialyltransferase and zona pellucida protein were considered of interest in ecotoxicology. The vitellogenin gene was selected for study as it has been widely used as a molecular marker of exposure to 17â-estradiol (E2) in teleosts. Gene expression was examined via northern blot, RT-PCR and Real-Time PCR relative to the housekeeping gene (18S rRNA). The expression of vitellogenin mRNA was observed a t 12 hours post-exposure, peaked at 48 hours according to northern blot analysis; and cleared within 4 days, partly consistent with RT-PCR. However, Real-time PCR yielded an inconclusive result, probably due to differences between pooled and individual samples. Vitellogenin in blood plasma was confirmed by western blot, found to be significantly increased and retained in the plasma in fish treated with E2 compared to controls. It was concluded that vitellogenin mRNA is a molecular marker of exposure to 17â-estradiol in the rainbowfish, and could potentially be used as a marker of exposure to environmental estrogenic chemicals. Further investigations of the expression of genes in the cDNA library, could establish other molecular markers of ecotoxicological interest in M. fluviatilis.
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Introdukuojųjų Ponto–Kaspijos šoniplaukų ir mizidžių poveikis ešerių (Perca fluviatilis) mitybai bei auginimui Lietuvos ežeruose / The influence of introduced ponto–caspian scuds and opossum shrimps on perch (perca fluviatilis) diet and growth rate in the lakes of lithuania

Rakauskas, Vytautas 25 November 2010 (has links)
Lietuvos ežeruose siekiant praturtinti žuvų maistinius išteklius buvo introdukuota keletas Ponto-Kaspijos komplekso šoniplaukų bei mizidžių rūšių. Manyta, kad verslinės žuvys, tame tarpe ir ešeriai specializuosis maitintis šiais vertingais maisto objektais. Atlikti tyrimai parodė, kad ešeriai introdukuotomis rūšimis pradeda maitintis jau pirmaisiais gyvenimo metais. Ešeriams augant, minėtų vėžiagyvių reikšmė jų mityboje didėja. Ežeruose, kur introdukuotosios rūšys litoralėje suformavo gausias populiacijas, šių vėžiagyvių ešerių skrandžiuose pasitaiko daugiau lyginant su ežerais su negausiomis vietinių vėžiagyvių populiacijomis. Atliktos analizės parodė, kad vis tik invaziniai vėžiagyviai kryptingai nekaičia ešerių mitybinės nišos pločio, o ešeriai introdukuotais Ponto-Kaspijos komplekso vėžiagyviais selektyviai nesimaitina. Ešeriai yra „generalistai“ ir maitinasi tuo metu aplinkoje esančiais, lengvai prieinamais bei tinkamais pagal dydį maisto objektais. / SUMMARY The influence of the introduced Ponto-Caspian scuds and opossum shrimps on perch (Perca fluviatilis) diet and growth rate in the lakes of Lithuania The purpose of this study was to examine perch (Perca fluviatilis) feeding habits and diet differences between two types of lakes that differ in having and lacking abundant littoral populations of introduced Ponto-Caspian opossum shrimps and scuds. The growth of the perch has been performed in order to answer whether introduced crustaceans really improve fish food basis in lakes. 1104 individuals were used to perform their growth rate analysis. 861 individuals were used to clear their diet. Fish and littoral benthic animal’s samples were collected in 2004 – 2006 summer and fall seasons in 10 Lithuanian lakes (Dusia, Daugai, Asveja, Žeimenys, Šakarvų, Baluošai, Nedingis, Lavysas, Plateliai and Beržoras). Analyses show that perches consume introduced Ponto-Caspian crustaceans from their first year. Kruskal-Walis ANOVA test show significant general lake effect on consuming rate of both scuds and opossum shrimps when comparing between three types of lakes that differ in littoral scuds and opossum shrimps population size. There was bigger consuming rate in lakes with larger crustacean’s populations in four different age groups of perch. We found significant correlations between relative biomass of littoral scuds in the benthic communities and in the perch stomach in three different age groups of perch. However we failed to find... [to full text]

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