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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.
41

Studies on in vitro maturation of dog oocytes to improve maturation rate and development potentials

Salavati, Mazdak January 2013 (has links)
In vitro maturation of dog oocytes has always been the main obstacle preventing reproductive biologist from producing canine in vitro cultured embryos. The unsuccessful oocyte maturation in canine species originates from their unique physiological and biological specifications. Ovulation of dominant follicles in bitch (6-12 in each oestrous cycle) occurs at prophase I stage of oocyte nucleus and meiotic resumption develops during 3-5 days of oviductal transition. During this PhD thesis, studies were designed in order to speculate characteristics of canine oocyte maturation in vitro in terms of maturation media components, gas composition of the incubator and hormonal requirements. Level of oxidative stress during 72h (culture period) of in vitro maturation showed that 5%O2, 5% CO2 and 90% N2 composition improves meiotic resumption and reduces degeneration rate significantly compared to 5% CO2 in air. Utilization of caffeine as a non specific phosphodiesterase inhibitor at 10mM for 12h at the beginning of the 72h culture (12+60) also improved MII maturation rate (16.9% ± 2.4; P < 0.05). Among several hormonal treatments recombinant porcine Growth Hormone (PGH) at 100ng/ml and Melatonin (MTN) at 100nM concentrations had outstanding improvement over meiotic resumption (28.9% ±10.0 and 56.2% ±8.6 respectively; P < 0.05). Attempts were made to study developmental potentials of optimally matured oocytes by parthenogenetic activation (PA) and in vitro fertilization (IVF) using chilled semen. Partial digestion of the zona pellucida prior to IVF improved the cleavage rate at 48h 6.4% ± 0.3 and resulted in production of a single 8 cell embryo. Moreover; canine follicular cells were culture in order to characterize their primary culture morphology and steroidogenic responsiveness to physiological and pharmaceutical substances. Immunolocalization of aromatase (CYP19) positive cell clumps, presumptive oestrogen producing colonies, was identified. This primary culture also maintained its steroidogenic machinery up to 96h (measured by radioimmunoassay) with a significant increase in production of estradiol and progesterone after 72h compare to the start of the culture.
42

Avaliação reprodutiva do macho de Tomodon dorsatus (dipsadidae), do estado de São Paulo, nas diferentes estações do ano

Abud, Luciane Lily January 2018 (has links)
Orientador: Bruno César Schimming / Resumo: O ciclo reprodutivo das serpentes é caracterizado a partir de análises macroscópicas e histológicas do trato reprodutivo ao longo do ano. Estudos sobre eventos reprodutivos masculinos normalmente, não incluem qualquer análise microscópica, estando sujeitos a conclusões equivocadas. A histologia pode ser utilizada para caracterizar a condição testicular e ciclo espermatogênico em serpentes. Portanto, o uso dela é indispensável para o estudo do ciclo reprodutivo em serpentes. Este trabalho teve como objetivo realizar uma análise da morfologia do trato reprodutivo da serpente Tomodon dorsatus nas diferentes estações do ano. Para tanto, foram utilizados 50 espécimes de Tomodon dorsatus provenientes da coleção hepetológica do Instituto Butantan e 6 indíviduos vivos que foram eutanasiados posteriormente. O testículo, rim e ducto deferente foram mensurados e em seguida coletados fragmentos destinados para análise histológica. A largura do túbulo seminífero foi maior no outono (p=0,001); o epitélio obteve maior altura no verão (p=0,001). Os testículos estavam ativos ao longo do ano, porém, a espermiogênese obteve um pico no verão; no outono, a maioria dos indivíduos estava em espermiogênese ou iniciando a regressão; no inverno, alguns indivíduos estavam em recrudescência ou em regressão. Espermatozoides foram encontrados no lumem dos ductos deferentes em todas as estações do ano. O comprimento renal foi maior no outono (p=0,027) e não houve diferença significativa na largura renal (p... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The snake reproductive cycle is characterized by macroscopical and histological analysis of the reproductive tract. Studies on reproductive cycle in the male do not included histological analysis, which can lead a erroneous conclusions. The histology is used to characterized the testicular conditions and spermatogenesis in snakes. Thus, the histology is pivotal to study the reproductive cycle in snakes. The aim of this study was analysed the morphology of the male reproductive tract in the snake Tomodon dorsatus in the different seasons of the year. For this purpose, 50 specimens of Tomodon dorsatus from the hepetological collection of the Butantan Institute and 6 living individuals were used and later euthanized. The testicular, kidney and vas deferens were measured and then fragments were collected for histological analysis. The width of the seminiferous tubule was greater in the autumn (p = 0.001); the epithelium had higher height in the summer (p = 0.001). The testicles were active throughout the year, however, the spermiogenesis peaked in the summer; in the fall, most individuals were either in espemiogenesis or initiating regression; in winter, some individuals are in recrudescence or regression. There were spermatozoa in the lumen of the vas deferens at all seasons of the year. Renal length was higher in autumn (p = 0.027), width did not show a significant increase (p = 0.237). The width of the renal sexual segment (SSR) was higher in winter (p = 0.001), as well as the... (Complete abstract click electronic access below) / Mestre
43

Biologia reprodutiva de Enyalius perditus (Jackson, 1978) e Enyalius iheringii (Boulenger, 1885) (Squamata: Leiosauridae) / Reproductive biology of Enyalius perditus (Jackson, 1978) and Enyalius iheringii (Boulenger, 1885) (Squamata: Leiosauridae)

Migliore, Serena Najara 19 December 2016 (has links)
Enyalius perditus e Enyalius iheirngii são duas espécies de lagartos semi- arborícolas pertencentes à nova família Leiosauridae. Apresentam hábitos diurnos, são forrageadores ativos, e estão distribuídos ao longo da Mata Atlântica. E. perditus ocorre na porção sudeste enquanto E. iheringii nas porções sudeste e sul com registros de co-ocorrência em áreas do Estado de São Paulo. Apesar de sua ampla distribuição pouco se conhece sobre a ecologia e menos ainda sobre a biologia reprodutiva do gênero Enyalius. Além disto, informações sobre o comportamento reprodutivo de corte, época de cópula, desova e nascimento dos filhotes são praticamente inexistentes. Para tanto, este estudo investigou a estratégia reprodutiva de ambas as espécies através da dissecção de animais provenientes de coleções científicas, de cativeiro e de coletas em campo. Machos e fêmeas de E.iheringii atingiram maturidade sexual em tamanhos similares. Ambas as espécies são mais abundantes durante a estação chuvosa do que na estação seca. Ciclo de fêmeas de E. iheringii são mais estendidos e há possibilidade dos machos estocarem o espermatozoides nos ductos deferentes durante todo o ano. Foram encontradas fêmeas de E. iheringii estocando espermatozoides durante a primavera no infundíbulo e no outono dentro das criptas de estocagem da junção uterino-vaginal. Nas fêmeas de E. perditus a reprodução é altamente sazonal e ocorre nos períodos mais quentes e úmidos do ano. / Enyalius perditus and Enyalius iheirngii are two semi-arboreal lizard species that belong to the new family Leiosauridae. These specimens present daytime behavior and are active forragers distributed across the Atlantic Rainforest. E. perditus are found in the Southeast and E. iheringii in the Southeast and South. They also present co- occurrence in some areas at São Paulo state. Despite their wide distribution, little is known about their ecology and even less about the reproductive biology of their genera. The information about the reproductive biology of these animals is scarce on the other hand data regarding courtship behavior, mating season, spawning and offspring birth is virtually absent. For this, this study investigated the reproductive strategy of both species through the dissection of animals from scientific collections, captivity and field collections. In E.iheringii males and females reached sexual maturity in similar sizes. Both species are more abundant during the rainy season than in the dry season. Cycle of females of E. iheringii appear more extended and there is possibility of males stocking the spermatozoa in the vas deferens throughout the year. Females of E. iheringii were found stocking sperm during the spring in the infundibulum and in the fall within the storage crypts of the uterine-vaginal junction. In E. perditus females reproduction is highly seasonal and occurs during the hottest and wettest periods of the year.
44

Biologia reprodutiva de Rhinelepis aspera Spix & Agassiz,1829 (Osteichthyes,Loricariidae) no submédio São Francisco,Petrolina-PE

SOUZA, Elizângela Maria de 10 April 2006 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-10T12:37:27Z No. of bitstreams: 1 Elizangela Maria de Souza.pdf: 678116 bytes, checksum: 59d0516089dfeb649af279bd353a7fee (MD5) / Made available in DSpace on 2017-02-10T12:37:27Z (GMT). No. of bitstreams: 1 Elizangela Maria de Souza.pdf: 678116 bytes, checksum: 59d0516089dfeb649af279bd353a7fee (MD5) Previous issue date: 2006-04-10 / Aiming to investigate the population and reproductive biology of the “black scale fish” Rhinelepis aspera Spix & Agassiz, 1829, studies have been carried through in a section of the Submiddle São Francisco River Valley , next to the city of Petrolina-PE, located 09º 09' of South Latitude and 40º 22" West of Longitud. Two hundred forty eight specimens were catched by net and mesh (meshes from 8 to 14 cm) in the period of February of 2005 to January of 2006. For each individual was determined sex, total length (Tl-cm), total weight (Tw-g) and gonadal weight (Gw-g). The morfometric description was effected to characterize them macroscopically, defining the GSI (Gonadossomatic Index). Microscopic characterizations had been made to describe the histological aspects of the ovaries and the testicles. The stages of gonadal development were described and a scale of maturity was established (1 - rest, 2 - initial maturation, 3 – mature or advanced maturation and 4 - disposed or spawned) in function of the histological characteristics. During the period collect there was a slight predominance of females (56,4%). The females were more numerous in the classes of bigger lengths and had reached the length of the first maturation (L50) about 41 cm. Themales had reached the length of the first maturation (L50) about 41,5 cm. From 50,5 cm all individuals, males and females, are apt to participate in the reproductive process (L100). It was obtained for all the population of R. aspera the value of angular coefficient (q ≅ 3. 0), as to the relation total weight/ total length, the growth is an isometric type. The GSI presented greater values in the months of February and December 2005 for females and in the months of April 2005 and January 2006 for males. / Visando investigar a biologia reprodutiva do cascudo-preto Rhinelepis aspera Spix & Agassiz, 1829, estudos foram realizados num trecho do submédio do rio São Francisco, próximo à cidade de Petrolina-PE (09º 09’ de Latitude Sul e 40º 22’ de Longitude Oeste). Foram capturados por meio de tarrafa e rede de espera (malhas de 8 a 14 cm entre nós) 248 exemplares no período de fevereiro de 2005 a janeiro de 2006. Para cada indivíduo foi determinado o sexo, comprimento total (Ct-cm), peso total (Pt-g) e peso gonadal (Pg-g). A descrição morfométrica foi efetuada para caracterizá-las macroscopicamente, definindo o IGS (índice gonadossomático). Caracterizações microscópicas foram feitas para descrever os aspectos histológicos dos ovários e dos testículos. Os estágios de desenvolvimento gonadal foram descritos sendo estabelecida uma escala de maturidade (1 – repouso, 2 – maturação inicial, 3 – maturação avançada/ maduro e 4 – desovado ou espermiado) em função das características histológicas. Durante o período de coleta houve ligeira predominância de fêmeas (56,4%). As fêmeas foram mais numerosas nas classes de maiores comprimentos e atingiram o comprimento da primeira maturação (L50) com cerca de 41cm. Os machos atingiram o comprimento da primeira maturação (L50) com cerca de 41,5 cm. A partir de 50,5cm todos os indivíduos machos e fêmeas estão aptos a participar do processo reprodutivo (L100). Obteve-se para toda população de R. aspera o valor do coeficiente angular (q ≅ 3.0), conforme a relação peso total/ comprimento total, cujo crescimento é do tipo isométrico. O IGS apresentou maiores valores nos meses de fevereiro e dezembro de 2005 para fêmeas e nos meses de abril de 2005 e janeiro de 2006 para machos.
45

Biologia reprodutiva da albacora Bandolim (Thunnus Obesus) no oceano Atlântico Oeste Tropical

FIGUEIREDO, Marina Bezerra 23 February 2007 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-02-16T14:56:11Z No. of bitstreams: 1 Marina Bezerra Figueiredo.pdf: 4281028 bytes, checksum: 769a66f89e02f5c1359899b741605fea (MD5) / Made available in DSpace on 2017-02-16T14:56:11Z (GMT). No. of bitstreams: 1 Marina Bezerra Figueiredo.pdf: 4281028 bytes, checksum: 769a66f89e02f5c1359899b741605fea (MD5) Previous issue date: 2007-02-23 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The study presents information about the reproductive characterísticas of bigeye tuna (Thunnus Obesus0. Were obtained 1082 samples of this species in the tropical Western Atlantic between July of 2004 and June of 2006. Were realized 873 (522 females and 351 males) histological cuts and observations of the present oocytes, analyzed with microscopy to determine the stage of gonadal development. For the females were determined 5 maturational stages: immature, initial and advanced maturation, spawning and resting. The fork length of the samples varied from 62 to 210 cm, and the sexual ratio was 1.46:1 (female:male). The females of bigeye tuna with high values of Gonadossomatic Index associated with advanced maturation were found during the first trimester, suggesting that this species has bigger reproductive activity in this period.The L for females was 92.8 cm and the males 82.1 cm. The estimate mean fecundity through hydrated oocytes counting for this species was 3,971,328 oocytes. / O presente estudo fez um levantamento sobre as características reprodutivas da albacora bandolim (Thunnus Obesus). Para isso, foi obtido um total de 1082 amostras de gônadas da presente espécie no Atlântico oeste Tropical entre julho de 2004 e junho de 2006. foram realizados 873 (522 fêmeas r 351 machos) cortes histológicos e observações dos ovócitos presentes, analisados microscopicamente para determinação das fases de desenvolvimento gonadal. Para as fêmeas foram determinados 5 estágios maturacionais: maturo, maturação inicial e avançada, desovado e em repouso. O comprimento zoológico dos exemplares variou de 62 210 cm, e a proporção sexual foi de 1,46 fêmeas para um macho. A relação entre o Índice Gonadal e exemplares em maturação avançada mostrou que a albacora bamdolim parece possuir maior atividade reprodutiva no primeiro trimestre do ano. O tamanho de primeira maturação sexual para as fêmeas foi de 92,8 cm, já para os machos esse valor foi menos, 82,1 cm. A fecundidade média estimada através da contagem de ovócitos hidratados para a presente espécie foi de 3.971.328,13 ovócitos.
46

Populações de Hypsiboas albopunctatus (Anura, Hylidae) de ambientes urbanos e rurais diferem em relação às vocalizações, morfometria e aos tamanhos populacionais? / Hypsiboas albopunctatus (Anura, Hylidae) populations of urban and rural environments differ with respect to vocalization, morphology and population size?

Amaral, Ivan Borel 28 September 2009 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-10-17T20:27:19Z No. of bitstreams: 2 Dissertação - Ivan Borel Amaral - 2009.pdf: 844143 bytes, checksum: 1036d666696f26300e191f6b1659eb02 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-10-17T20:43:51Z (GMT) No. of bitstreams: 2 Dissertação - Ivan Borel Amaral - 2009.pdf: 844143 bytes, checksum: 1036d666696f26300e191f6b1659eb02 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-17T20:43:51Z (GMT). No. of bitstreams: 2 Dissertação - Ivan Borel Amaral - 2009.pdf: 844143 bytes, checksum: 1036d666696f26300e191f6b1659eb02 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2009-09-28 / In recent years, population declines of amphibians have been observed in different parts of the world. The process of fragmentation and destruction of habitats is considered the most threat to this diversity. Urbanization reduces species richness at assemblage of amphibian reproduction. Due to amphibians require a modest area for survival, some species can thrive in urban fragments. But small population sizes and isolation can cause the loss of genetic diversity and the extinction local. The advertisement calls are the most common vocalizations in anurans that primarily have the function to attract females and secondarily, serve to mediate aggressive interactions between males. For many species, individual reproductive success is directly proportional to the effort put in the corner. The variation between populations may be related to local adaptation, resource availability and reduced gene flow. This study aimed to test the following hypotheses: ( 1 ) Due to the effects of fragmentation and habitat destruction and urbanization , population sizes of Hypsiboas albopunctatus urban parks are smaller than the population size of rural populations , (2 ) There are differences morphometric H. albopunctatus between rural and urban environments , and ( 3 ) Due to the change of social structure as a function of fragmentation and influence of urban noise , there are differences in vocalizations of H. albopunctatus between rural and urban environments . The H. albopunctatus populations of urban and rural environments differ in population size , the body size and characteristics of the advertisement call. Urban populations were smaller than those of the rural environment. The results showed that populations are lower in smaller and changed urban fragments . Urban populations had a lower repetition rate of notes compared to rural environment . This fact may be related mainly to reduced population sizes and consequent behavioral change and structure of choirs of urban environments. It is unreasonable to reject the hypothesis that the sounds of car engines may influence the acoustic parameters of the corners of H. albopunctatus in urban environment. The population of H. albopunctatus Zoo vocalised in higher frequency bands and acoustic variable that is inversely related to body size of individuals as in other anurans. The population of this fragment was the one that differed from all others in both acoustic as morphometric characteristics. These results support the hypothesis that there are differences in the characteristics of the advertisement calls of Hypsiboas albopunctatus between rural and urban environments. The population of P. M. Jardim Botânico was the most distanced itself from the other urban populations in both acoustic and morphometric characteristics as the population size. This population was the most resembled the population characteristics of the rural environment. A same species of amphibian populations may have considerably differences in population structure, morphological and behavioral characteristics due to the fact that some are under the influence of the urban environment and other rural environment. The planning for the conservation of such populations requires more refined analysis that takes into account the aspects of ecological, behavioral and adaptive responses of this species in their specific environment. / Nos últimos anos, declínios populacionais de anfíbios têm sido observados em diversas partes do mundo. O processo de fragmentação e destruição de habitats é considerado uma das maiores ameaça a essa diversidade. A urbanização reduz a riqueza de espécies em assembleias de áreas de reprodução de anfíbios. Contudo, porque os anfíbios requerem uma área modesta para sua sobrevivência, algumas espécies podem ter sucesso em fragmentos urbanos. Mas, devido aos pequenos tamanhos populacionais e ao isolamento, sofrem perda de diversidade genética, podendo extinguir-se localmente. Os cantos de anúncio são as vocalizações mais comuns em anuros que, primariamente, têm a função de atrair as fêmeas e secundariamente servem para mediar interações agressivas entre os machos. Para muitas espécies, o sucesso reprodutivo individual é diretamente proporcional ao esforço empregado no canto. A variação entre populações pode estar relacionada com a adaptação local, a disponibilidade de recursos e a redução do fluxo gênico. Este trabalho teve por objetivo testar as seguintes hipóteses: (1) Devido aos efeitos da fragmentação e destruição de habitat e da urbanização, os tamanhos populacionais de Hypsiboas albopunctatus dos parques urbanos são menores que os tamanhos populacionais das populações rurais; (2) Há diferenças morfométricas de H. albopunctatus entre os ambientes rurais e os ambientes urbanos; e (3) Devido à alteração da estrutura social em função da fragmentação e influência de ruídos urbanos, há diferenças nas vocalizações de anúncio de H. albopunctatus entre os ambientes rurais e os ambientes urbanos. As populações de H. albopunctatus de ambientes urbanos e rurais diferiram nos tamanhos populacionais, nos tamanhos corporais e nas características do canto de anúncio. As populações urbanas foram menores que as do ambiente rural. Os resultados demonstraram que as populações são menores nos fragmentos urbanos menores e mais alterados. As populações urbanas apresentaram uma menor taxa de repetição de notas comparado ao ambiente rural. Esse fato pode estar relacionado principalmente com os tamanhos populacionais reduzidos e a consequente alteração comportamental e de estrutura dos coros dos ambientes urbanos. Não é razoável descartar a hipótese de que os sons de motores de veículos possam influenciar nos parâmetros acústicos dos cantos de H. albopunctatus no ambiente urbano. A população de H. albopunctatus do Jardim Zoológico vocalizou em faixas de frequências mais altas e essa variável acústica está inversamente relacionada com o tamanho corporal dos indivíduos como em outros anuros. A população desse fragmento foi a que mais se diferenciou de todas as outras, tanto nas características acústicas quanto morfométricas. Esses resultados corroboram a hipótese de que há diferenças nas características de cantos de anúncio de Hypsiboas albopunctatus entre os ambientes rurais e urbanos. A população do P. M. Jardim Botânico foi a que mais se distanciou das outras populações urbanas tanto nas características acústicas e morfométricas quanto no tamanho populacional. Esta população foi a que mais se assemelhou às populações do ambiente rural. Uma mesma espécie de anfíbio pode possuir populações que diferem consideravelmente em estrutura populacional, características morfológicas e comportamentais devido ao fato de algumas estarem sob a influência de ambiente urbano e outras de ambiente rural. O planejamento para a conservação de tais populações requer análises mais refinadas que levem em conta os aspectos de respostas ecológicas, comportamentais e adaptativas dessa espécie a seu determinado meio.
47

Cryoconservation ovarienne : Étude de la folliculogenèse in vitro chez l'ovin et chez<br />l'humain

Mery, Lionel 27 November 2008 (has links) (PDF)
La culture de cortex ovarien se pose comme une alternative à l'autogreffe après autoconservation ovarienne. Pour améliorer la survie folliculaire après congélation, nous avons évalué chez la brebis l'influence de l'épaisseur de cortex ; 0,5 vs 1mm, du support de culture et du cryoprotecteur DMSO 2M vs PROH 1,5M+sucrose 0,3M. L'épaisseur de tissu de 1mm sur filtre millicell avec le protocole de congélation DMSO 2M a montré les meilleurs résultats avec 39% de survie folliculaire au 4e jour de culture. Sur tissu frais de brebis et humain, nous avons exploré un éventuel déficit d'expression en culture de Gdf9, de Bmp15 et de leur récepteurs qui expliquerait le blocage de croissance folliculaire in vitro. Dans les deux modèles la présence des ARNm et des protéines de Gdf9 et Bmp15 est maintenue et l'expression protéique de leurs récepteurs BmprIA, BmprIB, BmprII est conservée. Ce travail montre que la survie en culture après cryoconservation peut être optimisée, la cause du blocage de croissance reste à définir
48

Production des embryons et cryoconservation des ovocytes chez la lapine : Application à la gestion des ressources génétiques.

Salvetti, Pascal 09 December 2008 (has links) (PDF)
Aujourd'hui, la congélation de l'embryon est la voie privilégiée pour la cryoconservation des ressources génétiques lapin au sein de la Cryobanque Nationale. Les objectifs de notre travail étaient d'optimiser la production des embryons et de développer une nouvelle voie de cryoconservation des ovocytes MII de lapin par congélation lente et par vitrification. Les expériences menées sur les traitements de superovulation et de synchronisation ainsi que sur le moment d'insémination par rapport au sevrage montrent que les conditions d'environnement des lapines sont plus importantes que la nature des traitements administrés. De plus, l'évaluation du métabolisme, de la structure et de la capacité de développement ovocytaire après réchauffement suggère que la vitrification et la congélation lente altèrent fortement les ovocytes par des lésions associées respectivement à leur importante sensibilité aux cryoprotecteurs et à la cristallisation intracellulaire.
49

Multidimensionnalité pour la détection de gènes influençant des caractères quantitatifs. Application à l'espèce porcine

Gilbert, Hélène 31 January 2003 (has links) (PDF)
Ce travail a pour but de développer des méthodes de détection de locus affectant les caractères quantitatifs, appelés QTL, à partir de l'information disponible sur des caractères corrélés et/ou des positions liées, chez les animaux d'élevage.<br />Les méthodologies ont été dans un premier temps caractérisées pour leurs puissances et leurs précisions d'estimation des paramètres (positions et effets des QTL) à partir de données simulées. Nous avons développé d'une part des méthodes multivariées, extrapolées de techniques décrites pour l'analyse de données issues de croisements entre populations supposées génétiquement fixées, et d'autre part des méthodes synthétiques univariées, développées à l'occasion de ce travail. Ces dernières méthodes permettent de synthétiser l'information due à la présence du (des) QTL déterminant plusieurs caractères dans une unique variable, combinaison linéaire des caractères. Le nombre de paramètres à estimer est ainsi indépendant du nombre de caractères étudiés, permettant de réduire fortement les temps de calcul par rapport aux méthodes multivariées. La stratégie retenue repose sur des techniques d'analyse discriminante. Pour chaque vecteur de positions testé, des groupes de descendants sont créés en fonction de la probabilité que les individus aient reçu l'un ou l'autre haplotype de leur père. Les matrices de (co)variance génétique et résiduelle spécifiques de la présence du (des) QTL peuvent alors être estimées. La transformation linéaire permet de maximiser le rapport de ces deux variabilités.<br />Les méthodes basées sur l'analyse de variables synthétiques permettent en général d'obtenir des résultats équivalents, voire meilleurs, que les stratégies multivariées. Seule l'estimation des effets des QTL et de la corrélation résiduelle entre les caractères reste inaccessible par ces méthodes. Une stratégie itérative basée sur l'analyse de variables synthétiques pour la sélection des caractères et des régions chromosomiques à analyser par les méthodes multivariées est proposée. Par ailleurs, nous avons quantité les apports des méthodologies multidimensionnelles pour la cartographie des QTL par rapport aux méthodes unidimensionnelles. Dans la majorité des cas, la puissance et la précision d'estimation des paramètres sont nettement améliorées. De plus, nous avons pu montrer qu'un QTL pléiotrope peut être discriminé de deux QTL liés, s'ils sont relativement distants.<br />Ces méthodologies ont été appliquées à la détection de QTL déterminant cinq caractères de composition corporelle chez le porc sur le chromosome 7. Deux groupes de QTL déterminant des types de gras différents, le gras interne et le gras externe, ont ainsi été discriminés. Pour chacun de ces groupes, les analyses multiQTL ont permis d'identifier au moins deux régions chromosomiques distinctes déterminant les caractères.
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Growth, Reproductive Life-History Traits and Energy Allocation in Epinephelus guttatus (red hind), E. striatus (Nassau Grouper), and Mycteroperca venenosa (yellowfin grouper) (Family Serranidae, Subfamily Epinephelinae)

Cushion, Nicolle Marie 08 June 2010 (has links)
Fish populations are regulated by both external environmental factors, e.g., water quality parameters and habitat, and internal reproductive biology and physiology processes. For many species and populations there is often ample external information, while critical internal, i.e., life-history trait (LHT), information is not available. For this study, I determined LHTs and energy allocation patterns for Epinephelus guttatus (red hind), E. striatus (Nassau grouper), and Mycteroperca venenosa (yellowfin grouper) harvested from The Bahamas. I determined age ranges, and how growth patterns and rates differed among the study species. The maximum ages were: 17, E. guttatus; 22, E. striatus; and 13, M. venenosa. Epinephelus striatus was estimated to have the slowest, while M. venenosa had the fastest growth rate. A gonad histological classification system and the ageing data were used to determine the spawning seasons, sex ratios, size and age of sexual maturation and sex change and gonadosomatic indices (GSIs) for the study species. The peak spawning months were January-February for E. guttatus, December-January for E. striatus and March-April for M. venenosa. The fifty-percent sexual maturity estimates were 235 total length mm (Tlmm) (2.05 year old, yo), 435 Tlmm (4.00 yo), and 561 Tlmm (4.66 yo) for E. guttatus, E. striatus and M. venenosa, respectively. The size and age range of sex change for E. guttatus was between 257-401 Tlmm, ~4-5 years old and between 716-871 Tlmm, ~8-9 yo for M. venenosa. I determined protein and lipid concentrations in muscle and gonad tissues to ascertain energy allocation patterns. For all species and sexes except for female E. guttatus, the proportion of energy delegated to somatic growth declines as a fish grows longer, while reproduction energy allocation increases. The results of each study were compared to previous studies conducted throughout the tropical western Atlantic Ocean, and were related to species-specific ecological and spawning behaviors. The findings of each study highlight that the LHTs of the study species greatly differ and these differences will impact population dynamics and need to be considered for management initiatives. In the final chapter, the effects of fishing on LHTs are reviewed and fishery management options are discussed.

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