O objetivo dessa pesquisa foi avaliar aspectos genéticos que relacionados à produção in vitro de embriões na raça Guzerá. O primeiro estudo focou na estimação de (co) variâncias genéticas e fenotípicas em características relacionadas a produção de embriões e na detecção de possível associação com a idade ao primeiro parto (AFC). Foi detectada baixa e média herdabilidade para características relacionadas à produção de oócitos e embriões. Houve fraca associação genética entre características ligadas a reprodução artificial e a idade ao primeiro parto. O segundo estudo avaliou tendências genéticas e de endogamia em uma população Guzerá no Brasil. Doadoras e embriões produzidos in vitro foram considerados como duas subpopulações de forma a realizar comparações acerca das diferenças de variação anual genética e do coeficiente de endogamia. A tendência anual do coeficiente de endogamia (F) foi superior para a população geral, sendo detectado efeito quadrático. No entanto, a média de F para a sub- população de embriões foi maior do que na população geral e das doadoras. Foi observado ganho genético anual superior para a idade ao primeiro parto e para a produção de leite (305 dias) entre embriões produzidos in vitro do que entre doadoras ou entre a população geral. O terceiro estudo examinou os efeitos do coeficiente de endogamia da doadora, do reprodutor (usado na fertilização in vitro) e dos embriões sobre resultados de produção in vitro de embriões na raça Guzerá. Foi detectado efeito da endogamia da doadora e dos embriões sobre as características estudadas. O quarto (e último) estudo foi elaborado para comparar a adequação de modelos mistos lineares e generalizados sob método de Máxima Verossimilhança Restrita (REML) e sua adequação a variáveis discretas. Quatro modelos hierárquicos assumindo diferentes distribuições para dados de contagem encontrados no banco. Inferência foi realizada com base em diagnósticos de resíduo e comparação de razões entre componentes de variância para os modelos em cada variável. Modelos Poisson superaram tanto o modelo linear (com e sem transformação da variável) quanto binomial negativo à qualidade do ajuste e capacidade preditiva, apesar de claras diferenças observadas na distribuição das variáveis. Entre os modelos testados, a pior qualidade de ajuste foi obtida para o modelo linear mediante transformação logarítmica (Log10 X +1) da variável resposta. / The objective of this research was to evaluate genetic aspects permeating in vitro embryo production in Guzerá cattle. The first study aimed for estimating genetic and phenotypic (co)variances among embryo production traits and detecting possible genetic association with the age at first calving (AFC). Low and medium heritabilities were detected for oocyte and embryo production traits. A weak genetic association between artificial reproduction traits and AFC was identified. The second study evaluated genetic and inbreeding trends in the Brazilian Guzerá population. Female donors and in vitro produced embryos were considered as two subpopulations in order to perform comparisons and infer over differences in inbreeding and genetic annual variations. Embryos\' subpopulation showed higher genetic gains for age at first calving and milk production than donors\' subpopulation and the general population. Higher annual mean inbreeding values were also detected for the embryos\' subpopulation. The third study examined the effects of donor, sire (used for in vitro fertilization) and embryos\' inbreeding coefficient over in vitro embryo production traits in Guzerá cattle. Donors\' and embryos\' inbreeding effects over the analyzed traits were detected. Fourth and final study was designed to compare the performance of Linear and Generalized Linear Mixed Models under Restricted Maximum Likelihood method when fitting discrete variables. Four hierarchical models assuming different distributions for the response variable were fit to the (count) data. Inference was performed upon residual diagnostics and comparison of variance component ratios between models within each trait. Poisson models outperformed both linear (with and without variable transformation) and negative binomial models for goodness of fit and predictive ability despite clear differences in each trait\'s distribution. Logarithmic transformation (Log10 X +1) showed lowest goodness of fit among all models tested.

As a functional unit involved in both maintaining endocrine homeostasis and also producing mature eggs, the ovary plays a central role in female reproduction. The development and function of the ovarian follicles are controlled by gonadotropins released from the pituitary. It is widely accepted that the action of gonadotropins on ovarian follicles is mediated by paracrine/autocrine factors produced by the somatic cells surrounding the oocyte. Increasing evidence indicates that the Igf system is involved in mediating the action of gonadotropins in the ovary. Previously, we identified a gonad-specific Igf subtype (Igf3) distinct from Igf1 and Igf2. This fmding further highlights the importance of the Igf system in the fish ovary. In this thesis, efforts were made to understand the role of the Igf system in ovary using zebrafish as the model organism, and attention was focused on Igf3. / Because the expression of Igf3 is correlated with the LH receptor in zebrafish follicles, the regulation of igf3 by gonadotropins was subsequently studied in the ovary. The expression of igf3 was significantly up-regulated in both ovarian fragments and isolated follicles upon treatment with hCG in dose- and time-dependent manners. Treatment with 8-Br-cAMP or IBMX mimicked the effects of hCG on the expression of igf3 in follicles of different stages. / Four Igfs are present in zebrafish, and our results show that all four igfs are expressed in the ovary of zebrafish and exhibit the differential expression profiles during folliculogenesis. Using a primary culture of zebrafish follicle cells, we demonstrated that hCG stimulated igf2b and igf3 expression but suppressed igf2a expression. Moreover, the effect of gonadotropin could be mimicked by IBMX, which increased the intracellular levels of cAMP, suggesting the possible involvement of cAMP in the gonadotropin-based regulation and differential expression of igf2a, igf2b and igf3. These results also show that the Igf3 is the Igf subtype most sensitive to gonadatropin and cAMP. / In addition, the expression patterns of igf1, igf2a, igf2b, igf3, igf1ra and igf1rb were also studied during zebrafish embryogenesis. The unique temporal and spatial expression patterns of igf1, igf2a, igf2b, igf3, igf1ra and igf1rb were revealed by both real-time PCR and whole mount in situ hybridization, the results suggest divergent functions for these Igfs in early zebrafish development. / Taken together, the present studies provide substantial information about the Igf system, especially that of Igf3 in the zebrafish ovary. Data were gathered regarding Igf3 expression, regulation and functions, which is not only helpful for the understanding of the role of the Igf system in fish reproduction, but also contributes toward uncovering the ovarian signaling network involved in oocyte maturation across vertebrates. This study of igfs gene expression provides direct information to the study of Igf signaling in zebrafish. / To study the function of Igf3, bioactive recombinant Igf3 proteins were prepared using a bacterial expression system. Incubation of follicles with recombinant zebrafish Igf3 significantly enhanced oocyte maturation in time-, dose- and stage-dependent manners. The potential mechanisms of Igf3-induced oocyte maturation were then investigated. Igf3 stimulated oocyte maturation via a steroid-independent manner. Igf3 induced oocyte maturation through Igf1rs and the PI3 kinase, PDE3 and MAP kinase were necessary for Igf3-mediated oocyte maturation in zebrafish. / We first examined the gene expression patterns of Igf3 in the ovary. The igf3 gene in zebrafish was found to be alternatively spliced into two transcripts, with transcript variant 1 exclusively expressed in the gonads and transcript variant 2 only expressed during early development. Using specific antibodies developed for zebrafish Igf3, both the prepropeptide and the mature peptide forms of Igf3 were found to be predominantly expressed in the zebrafish ovary. Real-time PCR and in situ hybridization revealed that igf3 mRNA levels were relatively low in the early follicles but significantly increased after the mid vitellogenic stage (midstage III) and were high in the full grown follicles. In the full grown follicles, igf3 mRNA was detected primarily in the somatic follicular cells, with a low level of expression in the oocytes. Igf3 immunoreactivity was confined to the follicular cells alone. / Li, Jianzhen. / Advisers: Hui Zhao; Hon Ki Christopher Cheng. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 122-150). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

The embryonic development and pregnancy rates are influenced by variations in embryo in vitro production (IVP) systems and protocols for bovine embryos, such as gaseous atmosphere, culture media and the protein supply adopted in the different steps of IVP. Two studies were performed to evaluate the effect of O2 tension on in vitro maturation (IVM) and fertilization (IVF) of bovine oocytes, and the protein supply in the embryonic in vitro culture. Immature Cumulusoocytes complexes (COC) were recovered by transvaginal ultrasound guided follicular aspiration (OPU) from Bos taurus indicus donors from commercial programs and randomly assigned according to the number and quality of the COC. Standard bovine IVM procedure was carried out in modified TCM-199, added of FSH, LH, Oestradiol, EGF, insulin and 10% bovine fetal serum (FCS), for 24h. Frozen semen was selected by Percoll gradient (90, 60 and 30%). The insemination was performed with 2x106 spermatozoa/mL in Fert-Talp with heparin and PHE, for 18 to 22h. Presumptive zygotes were in vitro cultured (IVC) in SOFaaci during 6 to 9 days with 5%CO2, 5%O2 and 90% N2 in air. All steps of IVC were performed in an incubator at 39ºC with satured humidity. The cleavage and blastocyst rates were analysed by GLM procedure. Hatching, quality I blastocyst and pregnancy rates were compared by Chi-square Test with 5% of significance. In experiment I (11 replicates) IVM and IVF of COC (n=1092) were conducted under 5% CO2 (20% O2) in air or in 5%CO2, 5%O2 and 90% N2 (5%O2). Experiment II was divided in two steps (IIa and IIb). In experiment IIa (n=1745 COC), the IVM and IVF was followed by in vitro culture (IVC) in SOFaaci added of 4mg/mL bovine serum albumin (BSA) or 4mg/mL BSA+2% bovine fetal serum (BSA+FCS). In experiment IIb (n=704 COC), after standard IVM and IVF, IVC was performed in the two media of Experiment IIa (BSA and BSA+FCS) and in a third group the SOFaaci was added of 4mg/mL BSA+2% FCS (BSA+FCSD4) on day 4 of IVC. The viability was accessed by morphological evaluation in D2 (cleavage), D7 (blastocysts and quality categories), D9 (hatched blastocysts), D45 (experiment I) and D60 (experiment II; pregnancy rates), considering day zero (D0) as the fertilization day. In experiment I, no differences were found (P>0.05) in cleavage rates (69 and 70%), blastocyst in D7 (37 and 38%) and blastocyst quality I (79 and 74%) in an atmosphere of 5% or 20%O2, respectively. The hatching rate in D9 considering all COC submitted to IVM was higher (P<0.05) for the 5%O2 group (21%) compared to the IVM and IVF group under 20%O2 (11%). A pregnancy rate of transferred embryos at 45 days (n=278) was similar (P=0.15) between treatments (25.8 e 33.6% for 5%O2 e 20%O2 ,respectively ). In experiment IIa blastocyst rates (51%) and quality I blastocysts (41%) in D7, was higher (P<0.05) in BSA+FCS group compared to the BSA group (42 and 30%), respectively. In experiment IIb, blastocyst rates were higher (P<0.05) in group BSA+FCS (47%) and similar between BSA (34%) and BSA+FCSD4 (43%) groups. Blastocyst rates quality I were higher (P<0.05) for groups BSA+FCS (34%) and BSA+FCSD4 (32%), compared to the BSA group (19.9%). A pregnancy rate of the transferred embryos (n=820) was similar between treatments in experiments IIa and IIb. Considering pregnancy rates corresponding only to IVM COC (Experiment IIa), the rates were higher (P<0.05) for the BSA+FCS group (16%) than the BSA group (12%). There was no detrimental effect in IVP of bovine embryos and their pregnancy rates when IVM, IVF and IVC were performed in 5%O2, 5%CO2 and 90%N2. IVP of bovine embryos is increased by the addition of 2% FCS to the IVC medium without any detrimental effect on their morphological quality and pregnancy rates. On the other hand, pregnancy rates related to IVM of COC incremented by the addition of 2% de Fc to the IVC medium SOFaaci+BSA. / Diferenças nos protocolos e sistemas de produção in vitro (PIV) de embriões bovinos incluindo atmosfera gasosa, meios de cultivo e suplementação de proteína utilizados nas diferentes etapas da PIV, influenciam diretamente os resultados finais de desenvolvimento embrionário e prenhez. Dois experimentos foram conduzidos com o objetivo de avaliar a influência da concentração de oxigênio na maturação in vitro (MIV) e fecundação in vitro (FIV) de oócitos bovinos e da suplementação protéica no cultivo in vitro (CIV) de embriões bovinos. Complexos cumulus-oócitos imaturos (COC) obtidos de fêmeas Bos taurus indicus por aspiração folicular transvaginal guiada por ultra-sonografia (OPU) foram divididos homogeneamente quanto ao número e a qualidade entre os tratamentos, sendo maturados por 24h, em TCM-199 modificado, acrescido FSH, LH, Estradiol, EGF, Insulina e 10% de SFB. Sêmen congelado selecionado por gradientes de Percoll (2 x 106 células/mL) foi utilizado para a fecundação em Fert-TALP com heparina e PHE, por 18 a 22h. Os prováveis zigotos foram cultivados in vitro em SOFaaci por 6 a 9 dias em atmosfera de 5%CO2, 5%O2 e 90% N2. Todas as etapas foram conduzidas em estufa a 39ºC com umidade saturada. Os percentuais de clivagem e de blastocistos foram analisados pelo procedimento GLM. As taxas de eclosão dos blastocistos e de prenhez foram comparadas por Qui-quadrado com significância de 5%. No experimento I (11 repetições), a MIV e FIV dos COC (n=1092) foram realizadas sob atmosfera de 5% de CO2 em ar (20%O2) ou em 5%CO2, 5%O2 e 90% N2 (5%O2). O experimento II foi dividido em 2 etapas (IIa e IIb). No experimento IIa (n=1745 COC) após a MIV e FIV foi realizado o CIV em meio SOFaaci acrescido de 4mg/mL albumina sérica bovina (BSA) ou 4mg/mL de BSA + 2% de soro fetal bovino (BSA+SFB). No experimento IIb (n=704 COC), após a MIV e FIV, o CIV foi conduzido nos dois meios do experimento IIa (BSA e BSA+SFB) e um terceiro grupo onde o SOFaaci+BSA foi suplementado com 2% de SFB no quarto dia de cultivo (BSA+SFBD4). As avaliações morfológicas foram efetuadas no D2 (clivagem), D7 (blastocistos e grau de qualidade), D9 (blastocistos eclodidos) e taxa de prenhez aos 45 (experimento I) e 60 dias (experimento II), considerando-se o dia da fecundação como D0. No experimento I, não houve diferença (P>0,05) nas taxas de clivagem (69 e 70%), blastocistos em D7 (37 e 38%) e blastocistos qualidade I (79 e 74%) entre atmosfera de 5%O2 ou 20% de O2, respectivamente. A taxa de eclosão em D9 sob o total de oócitos MIV foi superior (P<0,05) no grupo 5%O2 (21%) comparado ao grupo MIV e FIV sob 20%O2 (11%). A taxa de prenhez aos 45 dias dos embriões transferidos (n=278) foi semelhante (P=0,15) entre os tratamentos (25,8 e 33,6% para 5%O2 e 20%O2 respectivamente). No experimento IIa, a taxa de blastocistos (51,5%) e de blastocistos qualidade I (41%) em D7, foi superior (P<0,05) para o grupo BSA+SFB em relação ao BSA (42 e 30%), respectivamente. No experimento IIb, a taxa de blastocistos foi superior (P<0,05) no grupo BSA+SFB e semelhante (P>0,05) entre o grupo BSA e BSA+SFBD4. A taxa de blastocistos qualidade I foi superior para os grupos BSA+SFB (34%) e BSA+SFBD4 (32,2%) em comparação ao grupo BSA (19,9%). A taxa de prenhez em relação aos embriões transferidos (n=820) foi semelhante entre os tratamentos nos experimentos IIa e IIb. A taxa de prenhez correspondente aos oócitos colocados para MIV foi superior (P<0,05) para o grupo BSA+SFB (16%) comparado ao grupo BSA (12%) no experimento IIa. Não há comprometimento da PIV de embriões bovinos bem como da taxa de prenhez quando a MIV, FIV e CIV são conduzidas com 5%O2, 5%CO2 e 90%N2. A produção in vitro de embriões é incrementada pela adição de 2% de SFB ao meio de CIV, sem prejudicar a qualidade morfológica dos mesmos e a taxa de prenhez. A porcentagem de prenhez produzida em relação aos COC colocados para MIV é aumentada pela adição de 2% de SFB ao meio de cultivo in vitro SOFaaci+BSA.

Gamete donors are actively searched by companies dedicated to assisted reproduction in the Spanish State, and advertising is not only legal but rather common. This thesis provides an overview of the main themes that arise from the analysis of mostly visual materials used to promote ovum donation in public spaces in Barcelona, and critically links them to current debates in intersectional feminist cultural studies of technoscience, bodily theory and visual studies. Conceptual and affective tensions between characterisations of women’s bodies, reproductive function and desires are identified and brought forward in terms that imply tropes of sacralisation, reification of cells/organs/tissues, and fragmentation of the bodily reality. It is argued that egg donation advertisements use an imagery that deeply connects with practices well rooted in Western biomedical traditions when it comes to female bodies, physiology and reproductive function, and that such practices are to be understood against the backdrop of neoliberalism. The analysis supports the idea that the publicity discourse of the assisted reproduction industry in Spain actively engages in a legitimation of the desire of biological parenthood as a right, in ways that value lives conceived in different circumstances and geopolitical contexts in radically different ways, and that can be interpreted as paving the way to prosurrogacy and/or eugenic positions. Future research is encouraged and directed towards exploring issues of agency, particularly in vulnerable groups such as migrant, poor, uneducated or racialised women. Further research is needed in order to build the foundations of a feminist ethical reflection on reproductive technologies and particularly of ovum donation.

O objetivo dessa pesquisa foi avaliar aspectos genéticos que relacionados à produção in vitro de embriões na raça Guzerá. O primeiro estudo focou na estimação de (co) variâncias genéticas e fenotípicas em características relacionadas a produção de embriões e na detecção de possível associação com a idade ao primeiro parto (AFC). Foi detectada baixa e média herdabilidade para características relacionadas à produção de oócitos e embriões. Houve fraca associação genética entre características ligadas a reprodução artificial e a idade ao primeiro parto. O segundo estudo avaliou tendências genéticas e de endogamia em uma população Guzerá no Brasil. Doadoras e embriões produzidos in vitro foram considerados como duas subpopulações de forma a realizar comparações acerca das diferenças de variação anual genética e do coeficiente de endogamia. A tendência anual do coeficiente de endogamia (F) foi superior para a população geral, sendo detectado efeito quadrático. No entanto, a média de F para a sub- população de embriões foi maior do que na população geral e das doadoras. Foi observado ganho genético anual superior para a idade ao primeiro parto e para a produção de leite (305 dias) entre embriões produzidos in vitro do que entre doadoras ou entre a população geral. O terceiro estudo examinou os efeitos do coeficiente de endogamia da doadora, do reprodutor (usado na fertilização in vitro) e dos embriões sobre resultados de produção in vitro de embriões na raça Guzerá. Foi detectado efeito da endogamia da doadora e dos embriões sobre as características estudadas. O quarto (e último) estudo foi elaborado para comparar a adequação de modelos mistos lineares e generalizados sob método de Máxima Verossimilhança Restrita (REML) e sua adequação a variáveis discretas. Quatro modelos hierárquicos assumindo diferentes distribuições para dados de contagem encontrados no banco. Inferência foi realizada com base em diagnósticos de resíduo e comparação de razões entre componentes de variância para os modelos em cada variável. Modelos Poisson superaram tanto o modelo linear (com e sem transformação da variável) quanto binomial negativo à qualidade do ajuste e capacidade preditiva, apesar de claras diferenças observadas na distribuição das variáveis. Entre os modelos testados, a pior qualidade de ajuste foi obtida para o modelo linear mediante transformação logarítmica (Log10 X +1) da variável resposta. / The objective of this research was to evaluate genetic aspects permeating in vitro embryo production in Guzerá cattle. The first study aimed for estimating genetic and phenotypic (co)variances among embryo production traits and detecting possible genetic association with the age at first calving (AFC). Low and medium heritabilities were detected for oocyte and embryo production traits. A weak genetic association between artificial reproduction traits and AFC was identified. The second study evaluated genetic and inbreeding trends in the Brazilian Guzerá population. Female donors and in vitro produced embryos were considered as two subpopulations in order to perform comparisons and infer over differences in inbreeding and genetic annual variations. Embryos\' subpopulation showed higher genetic gains for age at first calving and milk production than donors\' subpopulation and the general population. Higher annual mean inbreeding values were also detected for the embryos\' subpopulation. The third study examined the effects of donor, sire (used for in vitro fertilization) and embryos\' inbreeding coefficient over in vitro embryo production traits in Guzerá cattle. Donors\' and embryos\' inbreeding effects over the analyzed traits were detected. Fourth and final study was designed to compare the performance of Linear and Generalized Linear Mixed Models under Restricted Maximum Likelihood method when fitting discrete variables. Four hierarchical models assuming different distributions for the response variable were fit to the (count) data. Inference was performed upon residual diagnostics and comparison of variance component ratios between models within each trait. Poisson models outperformed both linear (with and without variable transformation) and negative binomial models for goodness of fit and predictive ability despite clear differences in each trait\'s distribution. Logarithmic transformation (Log10 X +1) showed lowest goodness of fit among all models tested.

La cryopréservation, dans le domaine de la reproduction médicalement assistée, constitue depuis de nombreuses années une branche suscitant beaucoup d’intérêts et d’espoirs. En effet, de nombreuses équipes de recherche se sont attelées à mettre au point et à améliorer des protocoles permettant de conserver les gamètes, les embryons et les tissus reproducteurs.<p>Malgré le fait que la cryopréservation soit une technique très attractive, elle peut avoir des effets délétères sur les cellules. Les protocoles expérimentaux visent donc à minimiser ces effets afin d’augmenter la survie et la compétence cellulaire après décongélation.<p><p>Les deux méthodes les plus utilisées, la congélation lente et la vitrification, présentent chacune des avantages et des inconvénients. En effet, la première ne permet pas d’éliminer la cristallisation intracellulaire. Quant à la seconde, elle empêche la formation de cristaux de glace mais pourrait provoquer une toxicité due à la forte concentration des cryoprotecteurs. <p><p>Cette thèse de doctorat propose plusieurs objectifs :<p><p>•\ / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished