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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.
81

Etude de la fertilité et du métabolisme des vaches laitières sélectionnées pour l'haplotype "fertil+" ou "fertil-" à un QTL de fertilité situé sur le chromosome 3 / Fertility and metabolism of dairy cows carrying "Fertil+" or "Fertil-" haplotype for a fertility QTL located on the chromosome 3

Coyral-Castel, Stéphanie 06 July 2012 (has links)
Au cours des dernières décennies, une dégradation de la fertilité des vaches laitières, parallèlement à une augmentation de la production laitière a été observée. Des régions du génome, les QTL, affectent la fertilité femelle. Le but de ce travail de thèse est d’étudier la fertilité et certains paramètres zootechniques chez des vaches Prim'Hosltein en première lactation choisies pour leur haplotype favorable "fertil+" ou défavorable "fertil-" pour un QTL de fertilité situé sur le chromosome 3. Ce phénotypage a montré une meilleure fertilité et un meilleur bilan énergétique dans la première semaine de lactation pour les vaches "fertil+" par rapport aux vaches "fertil-". De plus, les vaches "fertil-" ont un flux d’ingestion plus rapide. Au pic de mobilisation, certains gènes du QTL étaient différentiellement exprimés dans le tissu adipeux des deux haplotypes. Dans les cellules de la granulosa, un de ces gènes, nommé Kirrel, est plus exprimé chez les vaches "fertil+" et sa protéine recombinante inhibe la sécrétion de progestérone in vitro. Notre travail a permis d'affiner les interactions génotype-phénotype liées à un QTL de fertilité et de mettre en avant un des possibles rôles d'un gène de ce QTL dans la fonction de reproduction chez la vache laitière. / In recent decades, the dairy cow fertility has declined, in parallel with an increase in milk production. Some regions of the genome, named QTL, affect female fertility. The purpose of this thesis is to study fertility and some zootechnical parameters in Prim'Hosltein cows in first lactation chosen for their favorable haplotype "fertil+" or unfavorable haplotype "fertil-" for one fertility QTL on chromosome 3. This phenotyping showed better fertility and energy balance in the first week of lactation for "fertil+" than for "fertil-" cows. In addition, "fertil-" cows had a higher eating rate. At the peak of mobilization, the QTL genes are differentially expressed in adipose tissue of "fertil+" and "fertil-" cows. In granulosa cells, one of these genes, named Kirrel, is higher expressed in "fertil+" cows and its recombinant protein inhibits the secretion of progesterone in vitro. Our work has contributed to refine interactions genotype-phenotype linked to one fertility QTL and highlighted one of the possible roles of a gene which belongs to this QTL in the reproductive function in dairy cows.
82

Influência das concentrações de AGNE na qualidade oocitária e produção in vitro de embriões de vacas Holandesas no início da lactação / Influence of NEFA concentrations on oocyte quality and in vitro embryo production in Holstein cows during early lactation

Sala, Rodrigo Vasconcellos 26 June 2013 (has links)
O presente estudo avaliou a influência das concentrações de ácidos graxos não esterificados (AGNE Alto vs. Baixo) no dia 44±3 pós-parto, e dos dias pós-parto nas concentrações de metabólitos (ǰ-hidroxibutirato e glicose) e na qualidade oocitária e produção in vitro de embriões de vacas Holandesas no início da lactação (até 90 dias pós-parto). O experimento foi realizado na Fazenda Santa Rita (Agrindus S/A) localizada no município de Descalvado SP. A partir da data do parto foram selecionadas 30 vacas Holandesas para serem aspiradas a cada 14 dias em cinco diferentes momentos no início da lactação (30±3, 44±3, 58±3, 72±3 e 86±3 dias pós-parto). No momento da aspiração folicular (OPU), foram realizadas as colheitas de sangue para dosagem dos metabólitos, a avaliação do escore de condição corporal (ECC) e a contagem dos folículos visualizados. Os procedimentos de produção in vitro de embriões (maturação, fertilização e cultivo) foram realizados no laboratório da Bioembryo, localizado no município de Bauru - SP. A análise estatística foi realizada pelo procedimento GLM do SAS. Não se observou efeito de tratamento (Alto AGNE = 0,45 vs. Baixo AGNE = 0,52 mmol/L; P=0,20) e de tempo (30±3 = 0,54; 44±3 = 0,43; 58±3 = 0,43; 72±3 = 0,52 e 86±3 = 0,51 mmol/L; P=0,11) para as concentrações de β-hidroxibutirato. Para as concentrações de glicose não se verificou efeito do tratamento (Alto AGNE = 61,1 vs. Baixo AGNE = 63,6 mg/dL; P=0,26). No entanto, observou-se efeito de tempo para as concentrações de glicose (30±3 = 60,1; 44±3 = 63,0; 58±3 = 63,5; 72±3 = 62,1 e 86±3 = 63,0 mg/dL; P=0,03). O tratamento (Alto vs. Baixo AGNE) não influenciou a quantidade de folículos recrutados (P=0,36), oócitos totais recuperados (P=0,28) e oócitos viáveis (P=0,25). Assim como o tempo não alterou a quantidade de folículos recrutados (P=0,87), oócitos totais recuperados (P=0,42) e oócitos viáveis (P=0,44). A quantidade de oócitos grau I não foi influenciada pelo tratamento (Alto vs. Baixo AGNE; P=0,14). Porém, os dias pós-parto reduziram a sua quantidade (P=0,05). A quantidade de oócitos clivados por vaca aspirada (P=0,45) e a taxa de clivagem (P=0,95) não apresentaram diferenças estatísticas conforme as concentrações de AGNE (Alto vs. Baixo) no dia 44 pós-parto. Os dias pós-parto também não alteraram a quantidade de oócitos clivados por vaca aspirada (P=0,31) e a taxa de clivagem (P=0,80). Para a produção in vitro de embriões, a quantidade de blastocisto por vaca aspirada conforme as concentrações de AGNE (Alto = 0,4 vs. Baixo = 1,2; P=0,37) e os dias pós-parto (30±3 = 0,4; 44±3 = 0,7; 58±3 = 0,8; 72±3 = 0,9 e 86±3 = 1,2; P=0,39) não apresentaram diferenças estatísticas. Assim como, a taxa de blastocisto para os animais dos grupos (Alto AGNE = 6,2% vs. Baixo AGNE = 11,6%; P=0,51) e para os diferentes momentos pós-parto (30±3 = 4,8%; 44±3 = 8,9%; 58±3 = 10,7%; 72±3 = 10,0% e 86±3 = 12,8%; P=0,41). Conclui-se que a maior concentração de AGNE no dia 44 pós-parto em vacas Holandesas não influenciou as concentrações de β-hidroxibutirato e de glicose, assim como a qualidade e a produção in vitro de embriões. No entanto, o aumento dos dias pós-parto incrementou as concentrações de glicose e reduziu a quantidade de oócitos grau I de vacas holandesas submetidas à OPU/PIV até 90 dias após o parto. / The present study evaluated the influence of the days postpartum and the concentrations of non-esterified fatty acids (NEFA - High vs. Low) on concentrations of metabolites (β-hydroxybutyrate and glucose), oocyte quality and in vitro embryo production of Holstein cows during early lactation (90 days postpartum). The experiment was carried out in a commercial dairy farm (Santa Rita - Agrindus S/A), located at Descalvado - SP. At the calving moment, 30 Holstein cows were selected to be submitted to ovum pick-up (OPU) procedures each 14 days, in 5 different moments during the early lactation (30 ± 3, 44 ± 3, 58 ± 3, 72 ± 3 and 86 ± 3 days postpartum). Previously to the OPU session blood samples were collected for metabolite assay, body condition score (BCS) was recorded and the number of follicles able to be aspirated was also registered. The High and Low concentration of NEFA were stablished with the samples of day 44 ± 3 postpartum. The laboratory procedures for in vitro embryo production (in vitro maturation, fertilization and culture) were performed in the same laboratory (Bioembryo, Bauru - SP). Statistical analysis was performed by the GLM procedure of SAS. No effect was observed for different NEFA concentrations (High NEFA = 0.45 vs. Low NEFA = 0.52 mmol / L, P = 0.20), nor for days postpartum (30±3 = 0.54; 44±3 = 0.43; 58±3 = 0.43; 72±3 = 0.52 e 86±3 = 0.51 mmol/L; P=0.11) on β-hydroxybutyrate concentrations. Considering glucose concentrations there was no treatment effect (High NEFA = 61.1 vs. Low NEFA = 63.6 mg / dL, P = 0.26). However, the glucose concentrations were influenced by days postpartum (30±3 = 60.1; 44±3 = 63.0; 58±3 = 63.5; 72±3 = 62.1 e 86±3 = 63.0 mg/dL; P=0.03). Treatment (High vs. Low NEFA) did not impact the number of recruited follicles (P = 0.36), total oocytes recovered (P = 0.28) and viable oocytes (P = .25). As well as, time did not alter the amount of recruited follicles (P = 0.87), total oocytes recovered (P = 0.42) and viable oocytes (P = .44). The amount of grade I oocytes was not influenced by treatment (High NEFA vs. Low NEFA, P = 0.14). However, days postpartum reduced the quantity of grade I oocytes (P = 0.05). Also, no treatment effect (High and Low NEFA) was observed for number of cleaved oocytes per OPU session (P = 0.45) and cleavage rate (P = 0.95). In the same way, days postpartum had no influence in the amount of cleaved oocytes per OPU session (P = 0.31) and cleavage rate (P = 0.80). In addition, for the in vitro embryo production, the NEFA concentrations (High NEFA = 0.4 vs. Low NEFA = 1.2, P = 0.37) and days postpartum (30±3 = 0.4; 44±3 = 0.7; 58±3 = 0.8; 72±3 = 0.9 e 86±3 = 1.2; P=0.39) did not affect the number of blastocysts per OPU session. Also, the blastocyst rate was not influenced by treatment (High NEFA = 6.2% vs. Low NEFA = 11.6%, P = 0.51) and days postpartum (30±3 = 4.8%; 44±3 = 8.9%; 58±3 = 10.7%; 72±3 = 10.0% e 86±3 = 12.8%; P=0.41). It was concluded that high concentration of NEFA on day 44 postpartum in Holstein cows did not alter the concentrations of β- hydroxybutyrate and glucose, as well as, the oocyte quality and in vitro embryo production. However, the increase in days postpartum elevated the glucose concentrations and decreased the number of grade I oocytes of Holstein cows submitted to OPU and in vitro embryo production up to 90 days postpartum.
83

Short-term nutrition and its effect on ovulation in the ewe

Nottle, Mark Brenton. January 1988 (has links) (PDF)
Includes bibliographical references (leaves 143-165) Reports on studies undertaken to examine the physiological basis of the known ability of lupin grain to increase ovulation rate in the ewe.
84

Short-term nutrition and its effect on ovulation in the ewe / by Mark Brenton Nottle.

Nottle, Mark Brenton January 1988 (has links)
Includes bibliographical references (leaves 143-165) / xiii, 168 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Reports on studies undertaken to examine the physiological basis of the known ability of lupin grain to increase ovulation rate in the ewe. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, Waite Agricultural Research Institute, 1989
85

Granulocyte-macrophage colony stimulating factor (GM-CSF) : a paracrine regulator in the pre-implantation mouse uterus / Sarah A. Robertson.

Robertson, Sarah A. January 1993 (has links)
Bibliography: leaves 175-203. / xxix, 203 leaves, [14] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates whether cytokines influence the development of the embryo prior to implantation. / Thesis (Ph.D.)--University of Adelaide, Depts. of Obstetrics and Gynaecology and Microbiology and Immunology, 1993
86

Establishment of POP-1 asymmetry, a binary code for cell fate decisions in C. elegans /

Park, Frederick D. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (p. 68-76).
87

Influência das concentrações de AGNE na qualidade oocitária e produção in vitro de embriões de vacas Holandesas no início da lactação / Influence of NEFA concentrations on oocyte quality and in vitro embryo production in Holstein cows during early lactation

Rodrigo Vasconcellos Sala 26 June 2013 (has links)
O presente estudo avaliou a influência das concentrações de ácidos graxos não esterificados (AGNE Alto vs. Baixo) no dia 44±3 pós-parto, e dos dias pós-parto nas concentrações de metabólitos (ǰ-hidroxibutirato e glicose) e na qualidade oocitária e produção in vitro de embriões de vacas Holandesas no início da lactação (até 90 dias pós-parto). O experimento foi realizado na Fazenda Santa Rita (Agrindus S/A) localizada no município de Descalvado SP. A partir da data do parto foram selecionadas 30 vacas Holandesas para serem aspiradas a cada 14 dias em cinco diferentes momentos no início da lactação (30±3, 44±3, 58±3, 72±3 e 86±3 dias pós-parto). No momento da aspiração folicular (OPU), foram realizadas as colheitas de sangue para dosagem dos metabólitos, a avaliação do escore de condição corporal (ECC) e a contagem dos folículos visualizados. Os procedimentos de produção in vitro de embriões (maturação, fertilização e cultivo) foram realizados no laboratório da Bioembryo, localizado no município de Bauru - SP. A análise estatística foi realizada pelo procedimento GLM do SAS. Não se observou efeito de tratamento (Alto AGNE = 0,45 vs. Baixo AGNE = 0,52 mmol/L; P=0,20) e de tempo (30±3 = 0,54; 44±3 = 0,43; 58±3 = 0,43; 72±3 = 0,52 e 86±3 = 0,51 mmol/L; P=0,11) para as concentrações de β-hidroxibutirato. Para as concentrações de glicose não se verificou efeito do tratamento (Alto AGNE = 61,1 vs. Baixo AGNE = 63,6 mg/dL; P=0,26). No entanto, observou-se efeito de tempo para as concentrações de glicose (30±3 = 60,1; 44±3 = 63,0; 58±3 = 63,5; 72±3 = 62,1 e 86±3 = 63,0 mg/dL; P=0,03). O tratamento (Alto vs. Baixo AGNE) não influenciou a quantidade de folículos recrutados (P=0,36), oócitos totais recuperados (P=0,28) e oócitos viáveis (P=0,25). Assim como o tempo não alterou a quantidade de folículos recrutados (P=0,87), oócitos totais recuperados (P=0,42) e oócitos viáveis (P=0,44). A quantidade de oócitos grau I não foi influenciada pelo tratamento (Alto vs. Baixo AGNE; P=0,14). Porém, os dias pós-parto reduziram a sua quantidade (P=0,05). A quantidade de oócitos clivados por vaca aspirada (P=0,45) e a taxa de clivagem (P=0,95) não apresentaram diferenças estatísticas conforme as concentrações de AGNE (Alto vs. Baixo) no dia 44 pós-parto. Os dias pós-parto também não alteraram a quantidade de oócitos clivados por vaca aspirada (P=0,31) e a taxa de clivagem (P=0,80). Para a produção in vitro de embriões, a quantidade de blastocisto por vaca aspirada conforme as concentrações de AGNE (Alto = 0,4 vs. Baixo = 1,2; P=0,37) e os dias pós-parto (30±3 = 0,4; 44±3 = 0,7; 58±3 = 0,8; 72±3 = 0,9 e 86±3 = 1,2; P=0,39) não apresentaram diferenças estatísticas. Assim como, a taxa de blastocisto para os animais dos grupos (Alto AGNE = 6,2% vs. Baixo AGNE = 11,6%; P=0,51) e para os diferentes momentos pós-parto (30±3 = 4,8%; 44±3 = 8,9%; 58±3 = 10,7%; 72±3 = 10,0% e 86±3 = 12,8%; P=0,41). Conclui-se que a maior concentração de AGNE no dia 44 pós-parto em vacas Holandesas não influenciou as concentrações de β-hidroxibutirato e de glicose, assim como a qualidade e a produção in vitro de embriões. No entanto, o aumento dos dias pós-parto incrementou as concentrações de glicose e reduziu a quantidade de oócitos grau I de vacas holandesas submetidas à OPU/PIV até 90 dias após o parto. / The present study evaluated the influence of the days postpartum and the concentrations of non-esterified fatty acids (NEFA - High vs. Low) on concentrations of metabolites (β-hydroxybutyrate and glucose), oocyte quality and in vitro embryo production of Holstein cows during early lactation (90 days postpartum). The experiment was carried out in a commercial dairy farm (Santa Rita - Agrindus S/A), located at Descalvado - SP. At the calving moment, 30 Holstein cows were selected to be submitted to ovum pick-up (OPU) procedures each 14 days, in 5 different moments during the early lactation (30 ± 3, 44 ± 3, 58 ± 3, 72 ± 3 and 86 ± 3 days postpartum). Previously to the OPU session blood samples were collected for metabolite assay, body condition score (BCS) was recorded and the number of follicles able to be aspirated was also registered. The High and Low concentration of NEFA were stablished with the samples of day 44 ± 3 postpartum. The laboratory procedures for in vitro embryo production (in vitro maturation, fertilization and culture) were performed in the same laboratory (Bioembryo, Bauru - SP). Statistical analysis was performed by the GLM procedure of SAS. No effect was observed for different NEFA concentrations (High NEFA = 0.45 vs. Low NEFA = 0.52 mmol / L, P = 0.20), nor for days postpartum (30±3 = 0.54; 44±3 = 0.43; 58±3 = 0.43; 72±3 = 0.52 e 86±3 = 0.51 mmol/L; P=0.11) on β-hydroxybutyrate concentrations. Considering glucose concentrations there was no treatment effect (High NEFA = 61.1 vs. Low NEFA = 63.6 mg / dL, P = 0.26). However, the glucose concentrations were influenced by days postpartum (30±3 = 60.1; 44±3 = 63.0; 58±3 = 63.5; 72±3 = 62.1 e 86±3 = 63.0 mg/dL; P=0.03). Treatment (High vs. Low NEFA) did not impact the number of recruited follicles (P = 0.36), total oocytes recovered (P = 0.28) and viable oocytes (P = .25). As well as, time did not alter the amount of recruited follicles (P = 0.87), total oocytes recovered (P = 0.42) and viable oocytes (P = .44). The amount of grade I oocytes was not influenced by treatment (High NEFA vs. Low NEFA, P = 0.14). However, days postpartum reduced the quantity of grade I oocytes (P = 0.05). Also, no treatment effect (High and Low NEFA) was observed for number of cleaved oocytes per OPU session (P = 0.45) and cleavage rate (P = 0.95). In the same way, days postpartum had no influence in the amount of cleaved oocytes per OPU session (P = 0.31) and cleavage rate (P = 0.80). In addition, for the in vitro embryo production, the NEFA concentrations (High NEFA = 0.4 vs. Low NEFA = 1.2, P = 0.37) and days postpartum (30±3 = 0.4; 44±3 = 0.7; 58±3 = 0.8; 72±3 = 0.9 e 86±3 = 1.2; P=0.39) did not affect the number of blastocysts per OPU session. Also, the blastocyst rate was not influenced by treatment (High NEFA = 6.2% vs. Low NEFA = 11.6%, P = 0.51) and days postpartum (30±3 = 4.8%; 44±3 = 8.9%; 58±3 = 10.7%; 72±3 = 10.0% e 86±3 = 12.8%; P=0.41). It was concluded that high concentration of NEFA on day 44 postpartum in Holstein cows did not alter the concentrations of β- hydroxybutyrate and glucose, as well as, the oocyte quality and in vitro embryo production. However, the increase in days postpartum elevated the glucose concentrations and decreased the number of grade I oocytes of Holstein cows submitted to OPU and in vitro embryo production up to 90 days postpartum.
88

Optimization of ovarian superstimulation before ovum pick-up and in vitro embryo production in pregnant cattle

Hayden, Cameron 22 December 2022 (has links)
No description available.
89

Phosphorylation-dependent interaction of tyrosine 3 monooxygenase/tryptophan 5-monooxygenase activation protein (14 3-3) with PADI6 following oocyte maturation in mice

Snow, Alan J. 21 April 2008 (has links)
No description available.
90

Effets et mécanismes d'action d'une supplémentation en acides gras polyinsaturés n-3 sur la qualité ovocytaire, dans le contexte de la production d'embryons chez les vaches laitières / Effects and mechanisms of action of dietary n-3 polyunsaturated fatty acids, in dairy cattle, on oocyte quality in terms embryo production

Oseikria, Mouhamad 27 April 2017 (has links)
Ce travail a pour objectif d'étudier les effets d’une supplémentation en acides gras polyinsaturés (AGPI) n-3 à longues chaines sur la production d’embryons chez les vaches laitières. Le régime enrichi en AGPI n-3 a eu tendance à augmenter le nombre moyen des complexes ovocyte-cumulus récupérés par vache par session d’OPU par rapport au groupe témoin AGPI n-6. Une tendance à augmenter le nombre moyen par vache par session d’OPU de blastocystes et de blastocystes expansés avec une augmentation significative de blastocystes de qualité 1 et 2 ont été notés dans le groupe n-3. De même, les taux de blastocystes, de blastocystes expansés et de blastocystes de qualité 1 et 2 ont été significativement augmentés dans le groupe n-3. Nous avons aussi montré que l’addition d’acide docosahexaénoïque (DHA, C22:6 n-3) à une faible concentration (1μM) pendant la maturation in vitro des ovocytes bovins augmente significativement le taux de clivage et le taux et la qualité de blastocyste. La stimulation de FFAR4 (free fatty acid receptor 4), au cours de la MIV, par un agoniste spécifique (TUG 891), a entrainé des effets bénéfiques similaires à ceux du DHA (1μM) sur la compétence ovocytaire. Cela suggère que l’effet bénéfique du DHA pourrait passer, au moins partiellement, par l’activation du FFAR4. / We aimed to investigate whether dietary n-3 PUFA, in Prim‘Holstein dairy cattle in lactation, could influence reproductive performance in terms of embryo production. We showed that n-3 PUFA-enriched diet had a tendency to increase the average number of oocyte-cumulus complexes recovered per cow per OPU session. A tendency to increase the average numbers per cow per OPU session of blastocysts and expanded blastocysts with significantly increase of blastocysts of quality 1 and 2 were noted in the n-3 group compared to the n-6 group. Similarly, the rate of blastocysts, expanded blastocysts and blastocysts of quality 1 and 2 were significantly increased in the n-3 group compared to the n-6 group. We also showed that the addition of docosahexaenoic acid (DHA, C22:6 n-3) at low concentration (1μM) during IVM of bovine oocytes increased cleavage rate, blastocyst rate and embryo quality. DHA and free fatty acid receptor 4 (FFAR4) agonist TUG- 891 (1 or 5 μM) supplied during IVM similarly improved in vitro embryo development, suggesting that FFAR4 may, at least partially, mediate DHA beneficial effects on OCC, through activation of signaling pathways.

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