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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

Correlated response and sexual dimorphism in bidirectional selection experiments

Carte, Ira Franklin 12 June 2010 (has links)
Ph. D.
2

Genetic Considerations in the Evolution of Sexual Dimorphism

Wyman, Minyoung 08 January 2013 (has links)
Sexual differences are dramatic and widespread across taxa. However, a common genome between males and females should hinder phenotypic divergence. In this thesis I have used experimental, genomic, and theoretical approaches to study processes that can facilitate and maintain differences between males and females. I studied two mechanisms for the evolution of sexual dimorphism - condition-dependence and gene duplication. If sex-specific traits are costly, then individuals should only express such traits when they possess enough resources to do so. I experimentally manipulated adult condition and found that the sex-biased gene expression depends on condition. Second, duplication events can permit different gene copies to adopt sex-specific expression. I showed that half of all duplicate families have paralogs with different sex-biased expression patterns between members. I investigated how current sexual dimorphism may support novel dimorphism. With regards gene duplication, I found that related duplicates did not always have different expression patterns. However, duplicating a pre-existing sex-biased gene effectively increases organismal sexual dimorphism overall. From a theoretical perspective, I investigated how sexually dimorphic recombination rates allow novel sexually antagonistic variation to invade. Male and female recombination rates separately affect invasion probabilities of new alleles. Finally, I examined the assumption that a common genetic architecture impedes the evolution of sexual dimorphism. First, I conducted a literature review to test whether additive genetic variances in shared traits were different between the sexes. There were few significant statistical differences. However, extreme male-biased variances were more common than extreme female-biased variances. Sexual dimorphism is expected to evolve easily in such traits. Second, I compared these results to findings from the multivariate literature. In contrast to single trait studies, almost all multivariate studies of sexual dimorphism have found variance differences, both in magnitude and orientation, between males and females. Overall, this thesis concludes that sexual dimorphism can evolve by processes that generate novel sexual dimorphism or that take advantage of pre-existing dimorphism. Furthermore, a common genome is not necessarily a strong barrier if genetic variances differ between the sexes. It will be an exciting challenge to understand how mutation and selection work together to allow organisms differ in their ability evolve sexual dimorphism.
3

Genetic Considerations in the Evolution of Sexual Dimorphism

Wyman, Minyoung 08 January 2013 (has links)
Sexual differences are dramatic and widespread across taxa. However, a common genome between males and females should hinder phenotypic divergence. In this thesis I have used experimental, genomic, and theoretical approaches to study processes that can facilitate and maintain differences between males and females. I studied two mechanisms for the evolution of sexual dimorphism - condition-dependence and gene duplication. If sex-specific traits are costly, then individuals should only express such traits when they possess enough resources to do so. I experimentally manipulated adult condition and found that the sex-biased gene expression depends on condition. Second, duplication events can permit different gene copies to adopt sex-specific expression. I showed that half of all duplicate families have paralogs with different sex-biased expression patterns between members. I investigated how current sexual dimorphism may support novel dimorphism. With regards gene duplication, I found that related duplicates did not always have different expression patterns. However, duplicating a pre-existing sex-biased gene effectively increases organismal sexual dimorphism overall. From a theoretical perspective, I investigated how sexually dimorphic recombination rates allow novel sexually antagonistic variation to invade. Male and female recombination rates separately affect invasion probabilities of new alleles. Finally, I examined the assumption that a common genetic architecture impedes the evolution of sexual dimorphism. First, I conducted a literature review to test whether additive genetic variances in shared traits were different between the sexes. There were few significant statistical differences. However, extreme male-biased variances were more common than extreme female-biased variances. Sexual dimorphism is expected to evolve easily in such traits. Second, I compared these results to findings from the multivariate literature. In contrast to single trait studies, almost all multivariate studies of sexual dimorphism have found variance differences, both in magnitude and orientation, between males and females. Overall, this thesis concludes that sexual dimorphism can evolve by processes that generate novel sexual dimorphism or that take advantage of pre-existing dimorphism. Furthermore, a common genome is not necessarily a strong barrier if genetic variances differ between the sexes. It will be an exciting challenge to understand how mutation and selection work together to allow organisms differ in their ability evolve sexual dimorphism.
4

International genetic evaluations for udder health traits in dairy cattle /

Mark, Thomas, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.
5

Associação genética entre produção de leite, habilidade de permanência e ocorrência de mastite em vacas da raça holandesa em condições tropicais /

Irano, Natalia. January 2011 (has links)
Resumo: Objetivou-se com este trabalho estimar parâmetros genéticos para produção de leite, habilidade de permanência da vaca no rebanho e ocorrência de mastite clínica de vacas da raça Holandesa, bem como estudar as associações genéticas entre elas, com intuito de fornecer subsídios para a avaliação genética destas características. Foram analisados dados de 5.090 vacas da raça Holandesa que pariram no período de 1991 a 2010, pertencentes à Agropecuária Agrindus S.A.. Foram feitas duas análises multicaracterísticas, uma contendo as características produção de leite acumulada até 305 dias na primeira lactação (PL1), habilidade de permanência das vacas no rebanho (HP) até a terceira lactação e ocorrência de mastite clínica (OM) e, a outra, produção de leite acumulada até 305 dias (P305), HP e OM, ambas sob modelos animal e considerando as três primeiras lactações como medidas repetidas para P305 e OM. Os componentes de covariância foram obtidos por abordagem Bayesiana, utilizando o programa THRGIBBS1F90. As estimativas de herdabilidade, obtidas pela análise multicaracterísticas com a PL1, foram de 0,19; 0,28 e 0,13 para a PL1, HP e OM, respectivamente, enquanto que, na análise multicaracterísticas com a P305, as estimativas foram de 0,19; 0,31 e 0,14, respectivamente. As correlações genéticas foram de 0,38 entre PL1 e HP, 0,12 entre PL1 e OM e -0,49 entre HP e OM, em análise multicaracterísticas com a PL1 e, de 0,66 entre P305 e HP, -0,25 entre P305 e OM e - 0,52 entre HP e OM, em análise multicaracterísticas com a P305 / Abstract: The objective of this study was to estimate genetic parameters for milk yield, stayability and the occurrence of clinical mastitis in Holstein cows, as well as studying the genetic relationship between them, in order to provide subsidies for the genetic evaluation these traits. Records from 5,090 Holstein cows with calving varying from 1991 to 2010, belonging to the Agropecuária Agrindus S.A. Two standard multivariate analyses were carried out, one containing the trait of accumulated 305 day milk yields in first lactation (MY1), stayability (SA) to the third lactation and clinical mastitis (CM) and the other, accumulated 305 day milk yields (MY), SA and CM, considering the first three lactations as repeated measures for MY and CM. The covariance components were obtained by Bayesian approach using the program THRGIBBS1F90. The heritability estimates obtained by multivariate analysis with MY1, were 0.19, 0.28 and 0.13 for MY1, SA and CM, respectively, whereas the multivariate analysis with the MY, the estimates were 0.19, 0.31 and 0.14, respectively. The genetic correlations between MY1 and SA, MY1 and CM, SA and CM, respectively, were 0.38, 0.12, and -0.49. The genetic correlations between MY and SA, MY and CM, SA and CM, respectively, were 0.66, -0.25, and -0.52 / Orientador: Lucia Galvão de Albuquerque / Coorientador: Annaiza Braga Bignardi / Coorientador: Lenira El Faro / Banca: Vera Lucia Cardoso / Banca: Humberto Tonhati / Mestre
6

Associação genética entre produção de leite, habilidade de permanência e ocorrência de mastite em vacas da raça holandesa em condições tropicais

Irano, Natália [UNESP] 27 July 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-27Bitstream added on 2014-06-13T19:54:01Z : No. of bitstreams: 1 irano_n_me_jabo.pdf: 187304 bytes, checksum: 9f2cf22f2fa39eab86ecdfc75843adfe (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivou-se com este trabalho estimar parâmetros genéticos para produção de leite, habilidade de permanência da vaca no rebanho e ocorrência de mastite clínica de vacas da raça Holandesa, bem como estudar as associações genéticas entre elas, com intuito de fornecer subsídios para a avaliação genética destas características. Foram analisados dados de 5.090 vacas da raça Holandesa que pariram no período de 1991 a 2010, pertencentes à Agropecuária Agrindus S.A.. Foram feitas duas análises multicaracterísticas, uma contendo as características produção de leite acumulada até 305 dias na primeira lactação (PL1), habilidade de permanência das vacas no rebanho (HP) até a terceira lactação e ocorrência de mastite clínica (OM) e, a outra, produção de leite acumulada até 305 dias (P305), HP e OM, ambas sob modelos animal e considerando as três primeiras lactações como medidas repetidas para P305 e OM. Os componentes de covariância foram obtidos por abordagem Bayesiana, utilizando o programa THRGIBBS1F90. As estimativas de herdabilidade, obtidas pela análise multicaracterísticas com a PL1, foram de 0,19; 0,28 e 0,13 para a PL1, HP e OM, respectivamente, enquanto que, na análise multicaracterísticas com a P305, as estimativas foram de 0,19; 0,31 e 0,14, respectivamente. As correlações genéticas foram de 0,38 entre PL1 e HP, 0,12 entre PL1 e OM e -0,49 entre HP e OM, em análise multicaracterísticas com a PL1 e, de 0,66 entre P305 e HP, -0,25 entre P305 e OM e - 0,52 entre HP e OM, em análise multicaracterísticas com a P305 / The objective of this study was to estimate genetic parameters for milk yield, stayability and the occurrence of clinical mastitis in Holstein cows, as well as studying the genetic relationship between them, in order to provide subsidies for the genetic evaluation these traits. Records from 5,090 Holstein cows with calving varying from 1991 to 2010, belonging to the Agropecuária Agrindus S.A. Two standard multivariate analyses were carried out, one containing the trait of accumulated 305 day milk yields in first lactation (MY1), stayability (SA) to the third lactation and clinical mastitis (CM) and the other, accumulated 305 day milk yields (MY), SA and CM, considering the first three lactations as repeated measures for MY and CM. The covariance components were obtained by Bayesian approach using the program THRGIBBS1F90. The heritability estimates obtained by multivariate analysis with MY1, were 0.19, 0.28 and 0.13 for MY1, SA and CM, respectively, whereas the multivariate analysis with the MY, the estimates were 0.19, 0.31 and 0.14, respectively. The genetic correlations between MY1 and SA, MY1 and CM, SA and CM, respectively, were 0.38, 0.12, and -0.49. The genetic correlations between MY and SA, MY and CM, SA and CM, respectively, were 0.66, -0.25, and -0.52
7

Genetic improvement of plantation-grown Acacia auriculiformis for sawn timber production

Hai, Phi Hong, January 2009 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2009. / Härtill 5 uppsatser.
8

Genetic evaluation of clinical mastitis in dairy cattle /

Carlén, Emma, January 2008 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2008. / Härtill 4 uppsatser.
9

Multi-trait evaluation of Swedish warmblood stallions at station performance tests including field and competition records /

Olsson, Elisabeth, January 2006 (has links) (PDF)
Lic.-avh. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2006. / Härtill 2 uppsatser.
10

Genetic analysis of competition traits in Icelandic horses /

Elsa Albertsdóttir, January 2007 (has links) (PDF)
Licentiatavhandling (sammanfattning) Uppsala : Sveriges lantbruksuniverstet, 2007. / Härtill 2 uppsatser.

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