Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-09-12T18:07:34Z No. of bitstreams: 1 2011 - Paula Cardoso de Almeida Silva.pdf: 463902 bytes, checksum: 375c57bac0b880fd3baf2320ee7abb93 (MD5) / Made available in DSpace on 2016-09-12T18:07:34Z (GMT). No. of bitstreams: 1 2011 - Paula Cardoso de Almeida Silva.pdf: 463902 bytes, checksum: 375c57bac0b880fd3baf2320ee7abb93 (MD5) Previous issue date: 2012-01-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Embryo transfer (ET) is one of the most prominent techniques in the expansion of horse breeding, enabling the production of more products of a single mare per year, thus increasing the number of animals with high genetic value. The hormonal control of ovulation can be used as a tool to optimize the reproductive parameters and reduce the costs in an ET program. This study compared the effectiveness of lower doses than those traditionally used of Deslorelin and hCG, evaluating the time between ovulation and induction, the recovery rates and embryo attachment. The study was conducted at the Department of Animal Reproduction and Evaluation of UFRRJ. We conducted follow-up of 85 estrous cycles of Breton Postier and Mangalarga Marchador mares, when the mares presenting an ovarian follicle ? 35 mm, they were divided randomly into one of three treatments: G1 (n = 32) - treatment with 1000 IU (1.0 ml iv) of hCG (Chorulon ? - Intervet Schering-Plough Animal Health), G2 (n = 28) - treatment with 0.75 mg (0.75 ml iv) Deslorelin (Botupharma) and G3 (n = 28) - Treatment with 1.0 ml saline iv. Twenty four hours after application, ultrasound evaluation of ovarian was held every six hours up to ovulation. The donors were inseminated the day after induction and embryo collection took place in nine days after ovulation. The recovered embryos were immediately transferred to recipients previously synchronized, these pregnancy diagnosis was performed at 15 and 30 days old embryo. Data regarding the time between ovulation and induction and characteristics of follicular development were analyzed using analysis of variance (ANOVA), and the averages of these data were analyzed when needed by the Tukey test. The data regarding the percentage of mares ovulated in different periods, were analyzed using the Qui-quadrado (?2) 5%. In the case of embryo recovery rate, the data were analyzed using the Fisher exact test, however in relation to pregnancy rate was not possible to perform statistical analysis due to low sample size. The percentage of ovulation in up to 36 hours for G1, G2 and G3 were 34.4%, 13.3% and 8.7%, between 36 and 42 hours were 62.5%, 56.7% and 8.7%, from 42 to 48 hours were 0%, 20% and 13%, more than 48 hours were 3.1%, 10% and 69.6% respectively. Having thus a significant difference between treated and control groups (p <0.05). The embryo recovery rate was 75% (6/8) in G1 and G2, and 44.4% (4/9) in group G3, there was no significant difference between groups (p> 0.05). The rate of pregnancy at fifteen days old embryo was 69.2% (9/13). Thus the lower doses commonly used with inducing agents in question, were effective in promoting ovulation within 48 hours, but the use of these didn't result in significant improvement in the rates of embryo recovery. / A transfer?ncia de embri?es (TE) ? uma das t?cnicas de maior destaque na expans?o da equideocultura, possibilitando a produ??o de maior n?mero de produtos de uma mesma ?gua por ano, aumentando assim o n?mero de animais com alto valor gen?tico. O controle hormonal do momento da ovula??o pode ser usado como uma ferramenta para otimizar os par?metros reprodutivos e reduzir os custos em um programa de TE. O presente estudo comparou a efici?ncia de doses mais baixas do que as tradicionalmente utilizadas de hCG e Deslorelina avaliando o tempo entre a indu??o e a ovula??o, as taxas de recupera??o e fixa??o embrion?ria. O estudo foi desenvolvido no Departamento de Reprodu??o e Avalia??o Animal da UFRRJ. Foi realizado o acompanhamento de 85 ciclos estrais de ?guas da ra?a Bret?o Postier e Mangalarga Marchador, onde as ?guas ao apresentarem um fol?culo ovariano ? 35 mm foram divididas de maneira aleat?ria em um dos tr?s tratamentos: G1 (n = 32) ? tratamento com 1000 UI (1,0 ml i.v.) de hCG (Chorulon? - Intervet Schering-Plough Animal Health), G2 (n = 30) ? tratamento com 0,75 mg (0,75ml i.v.) de Deslorelina (Botupharma) e G3 (n=23) ? tratamento com 1,0 ml i.v. de solu??o salina. Vinte quatro horas ap?s a aplica??o, a avalia??o ultrassonogr?fica dos ov?rios passou a ser realizada a cada seis horas at? a detec??o da ovula??o. As ?guas doadoras foram inseminadas no dia seguinte a indu??o e as coletas de embri?o aconteceram no dia 9 ap?s a ovula??o. Os embri?es recuperados foram imediatamente transferidos para receptoras previamente sincronizadas, sendo o diagn?stico de gesta??o realizado aos 15 e 30 dias de idade embrionaria. Os dados referentes ao tempo entre indu??o e ovula??o e caracter?sticas do desenvolvimento folicular, foram analisados pelo m?todo de An?lise de Vari?ncia (ANOVA), sendo as m?dias desses dados analisadas quando necess?rio pelo teste de Tukey. Os dados referentes ao percentual de ?guas ovuladas em diferentes per?odos, foram analisados atrav?s do Qui-quadrado (?2) 5%. Em se tratando da taxa de recupera??o embrion?ria, os dados foram analisados atrav?s do teste Exato de Fisher, j? em rela??o a taxa de gesta??o n?o foi poss?vel realizar an?lise estat?stica devido ao baixo n?mero amostral. Os percentuais de ovula??o em at? 36 horas nos grupos G1, G2 e G3, foram 34,4 %, 13,3% e 8,7%, entre 36 e 42 horas, 62,5%, 56,7% e 8,7%, entre 42 e 48 horas, 0%, 20% e 13%, acima de 48 horas 3,1%, 10% e 69,6%, respectivamente. Havendo dessa maneira diferen?a significativa entre os grupos tratados e o controle (p < 0,05). A taxa de recupera??o embrion?ria foi de 75% (6/8) nos grupos G1 e G2 e 44,4% (4/9) no grupo G3; n?o houve diferen?a significativa entre os grupos (p > 0,05). J? a taxa de gesta??o aos quinze dias de idade embrion?ria foi de 69,2% (9/13). Deste modo as doses inferiores ?s comumente utilizadas, dos agentes indutores em quest?o, foram eficientes em promover a ovula??o em at? 48 horas, mas o uso destes, n?o resultou em melhora significativa nos ?ndices de recupera??o embrion?ria

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-06-14T16:02:16Z No. of bitstreams: 1 Victor Netto Maia.pdf: 954749 bytes, checksum: c7a0fb4acc16853fce85c1219537a372 (MD5) / Made available in DSpace on 2016-06-14T16:02:16Z (GMT). No. of bitstreams: 1 Victor Netto Maia.pdf: 954749 bytes, checksum: c7a0fb4acc16853fce85c1219537a372 (MD5) Previous issue date: 2015-03-31 / Much has been made in order to enhance the implementation and improve results of assisted reproductive biotechnologies in mares, however there are still few studies on vascularization of the corpus luteum (CL) and its relation to progesterone and angiogenic factors and their consequences when the ovulation is induced with deslorelin acetate. Mares were used in natural ovulation (GC) condition and induced (GT) with deslorelin (>35 mm follicles). In the experiment 1 ovulation and CL formation were followed by Doppler ultrasound (6.5 MHz), on days 4, 8 and 12 after ovulation (D0). Blood samples were obtained for progesterone assay by enzyme-immunoassay. The CLs were analyzed for vascularization, and images were recorded in video. Image analysis considered the percentage of luteal parenchymal area presenting color signals. The results were presented as mean ± epm. The average vascularization was in GC: 76.25 ± 8.98; 70.00 ± 8.16 and 57.50 ± 13.31 % and in GT: 85.00 ± 5.40, 90.00 ± 0.00 and 58.75 ± 9.24 % respectively for the days 4, 8 and 12 after ovulation. Progesterone concentrations were in GC: 6.21 ± 0.61; 5.82 ± 1.44 and 4.63 ± 0.79 ng/mL and GT: 6.10 ± 1.18; 4.67 ± 1.06 and 4.49 ± 1.37 ng/ml, respectively for the 4, 8 and 12 days after ovulation. The patterns of vascularization were higher in D4 and D8 compared to D12 of GT (P<0.05). However, there were no differences between groups or days in GC. The concentration of progesterone didn’t show significant differences between groups or studied days. In experiment 2, samples of CL were collected through ultrasound guided biopsy at the same time points after ovulation. The mRNA expression of VEGF, BFGF and LHR genes were analyzed by real time PCR. It was observed positive correlation between VEGF and LHR (P < 0.00001, r = 0.78), and it was possible to detect a higher LHR expression in D4 of GT than GC (p < 0.05), moreover this expression was higher in D4 and D8 than D12 of the GT group. bFGF was also expressed in luteal tissue in all days of both groups, however without statistical differences. It was concluded that deslorelin acetate was effective to induce ovulation in mares which did not alter the physiological responses of the corpus luteum in respect of the plasma progesterone concentration, however, affected luteal parenchyma vasculature. Also, LHR and VEGF expression was influenced by induced ovulation, with a lower level at D12, what must be expected in non-pregnant mares. / Muito tem sido feito no intuito de potencializar a aplicação e os resultados das biotécnicas de reprodução assistida na espécie equina, no entanto ainda são escassos os estudos sobre vascularização do corpo lúteo (CL) e sua relação com a progesterona em éguas induzidas com acetato de deslorelina; bem como, sua relação com os fatores angiogênicos e suas consequências quando a ovulação é induzida. Foram utilizadas éguas com ovulação natural (GC) e induzida (GT) com acetato de deslorelina (folículo >35mm). No primeiro experimento, os ovários foram acompanhados por ultrassonografia Doppler (6,5 MHz), nos dias 4, 8 e 12 após a ovulação (D0), quando também foram obtidas amostras de sangue para dosagem de progesterona. Os CLs foram analisados quanto a sua vascularização e as imagens gravadas em vídeo. A análise das imagens considerou o percentual de área do parênquima luteal que estava apresentando sinais coloridos. A concentração de progesterona foi analisada por enzima-imunoensaio. Os resultados foram apresentados em média ± erro padrão da média. As médias de vascularização foram no GC: 76,25 ± 8,98; 70,00 ± 8,16 e 57,50 ± 13,31% e no GT: 85,00 ± 5,40; 90,00 ± 0,00 e 58,75 ± 9,24%, respectivamente para os dias 4, 8 e 12 após a ovulação. As concentrações de progesterona foram no GC: 6,21 ± 0,61; 5,82 ± 1,44 e 4,63 ± 0,79 ng/mL e no GT: 6,10 ± 1,18; 4,67 ± 1,06 e 4,49 ± 1,37 ng/mL respectivamente para os dias 4, 8 e 12 após a ovulação. Os percentuais de vascularização apresentaram valores superiores nos dias 4 e 8 comparados ao D12 do GT (P<0,05), não havendo diferença nos dias do GC, nem entre os grupos a cada momento estudado. As concentrações de progesterona não apresentaram diferenças significativas entre grupos ou momentos estudados. No segundo experimento, foram tomadas amostras do CL através de biópsia guiada por ultrassom (5 MHz), nos mesmos períodos, e os fatores angiogênicos analisados pela expressão do mRNA dos genes VEGF, BFGF e receptor de LH (LHR) utilizando PCR em tempo real. Foi observada correlação positiva entre VEGF e LHR (P < 0,00001, r = 0,78). A expressão do LHR no D4 foi maior no GT do que no GC (p < 0,05). Também observou-se maior expressão nos D-4 e D-8 do que o D-12 do GT. A expressão do VGEF declinou no D12 comparado aos dias D4 e D8 do GT (P = 0,06). O bFGF foi expresso em todos os momentos dos dois grupos, porém sem diferença significativa. Conclui-se que o acetato de deslorelina, foi eficiente para a indução de ovulação em éguas, não alterando as respostas fisiológicas do corpo lúteo no que diz respeito a concentração plasmática de progesterona. No entanto, aumentou a responsividade do CL ao LH através de seus receptores, principalmente no quarto dia após a ovulação. Também a expressão do gene do VGEF foi influenciada pela indução da ovulação, tendo uma queda mais acentuada aos 12 dias após a ovulação, o que deve ser esperado em éguas não prenhes.

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-04-13T11:31:15Z No. of bitstreams: 2 Tese - Reinaldo Satoru Azevedo Sasaki - 2017.pdf: 17522623 bytes, checksum: 77ee39d0dc2c95c62a360ec39d490fab (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-04-13T13:26:59Z (GMT) No. of bitstreams: 2 Tese - Reinaldo Satoru Azevedo Sasaki - 2017.pdf: 17522623 bytes, checksum: 77ee39d0dc2c95c62a360ec39d490fab (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-13T13:26:59Z (GMT). No. of bitstreams: 2 Tese - Reinaldo Satoru Azevedo Sasaki - 2017.pdf: 17522623 bytes, checksum: 77ee39d0dc2c95c62a360ec39d490fab (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-03 / Background: Obesity affects the hypothalamus-pituitary-ovarian axis, and thus ovulation and menstrual cycle. As ovarian function is closely related to endocrine physiology, the ovulation association study with the body mass index will help to quantify the chance of anovulation in overweight patients. Objective: To evaluate the association between anovulation in the ultrasonographic monitoring and changes of weight of infertile patients without polycystic ovary of infertility's ambulatory of a university, where the outcome's factors were anovulation present or absent, and exposure factors: BMI nomal or above normal. Methods: Case-control study with 228 patients treated at a university in the city of Goiânia, divided into two groups according to the absence (group 1, cases = 110) or the presence of ovulation (group 2, control = 119) and assessed for normal body weight or above normal. Data analysis was performed using SPSS 22.0. Differences in proportions were assessed by Pearson's chi-square test (with Fisher correction where necessary) and Wilcoxon test. The value of p <0.05 was considered statistically significant. Among the patient groups were matched the average of the variables: age (1 = 32.45 years ± 4.13; 2 = 32.66 years ± 3.95), menarche (1 = 12.56 years ± 1.75; 2 = 12.61 years ± 1.6), FSH (6,11UI/L ± 1.98; 2 = 5.92 IU/L ± 1.61), prolactin (1 = 12.17 mcg/L ± 4.04; 2 = 12.09 mcg/L ± 3.98), TSH (1 = 1,824 mIU/L ± 0.749; 2 = 1.775 mU/L ± 0.844). Results: The anovulatory patients were likely to have irregular cycles 6.3 times more than the ovulatory patients. Among the ovulatory patients, those overweight had an average ovulation in 14.62° day of the cycle, and patients with normal BMI at 14.21°, with no statistical significance. The maximum mean follicular diameter reached before ovulation was 18.62 mm in patients with overweight. Among those with normal BMI, the average was 19.10 mm, with no statistical difference. In the group of anovulatory patients, the mean BMI was 25.64 kg/m² ± 4.24, and in the ovulatory patients, the mean BMI was 24.76 kg/m² ± 3.81. Among the anovulatory patients, 57 were overweight, while among ovulatory patients, 44 were in this same category of BMI. The odds ratio was 1.8655, with significant p value (p <0.05). Conclusion: There was association of anovulation with BMI above normal. Among the patients who ovulated, there was no association of the day of ovulation and maximum follicle diameter with BMI. There was association of anovulation with the report of irregularity of the cycle. / Introdução: A obesidade afeta o eixo hipotálamo-hipófise-ovariano, e portanto, a ovulação e o ciclo menstrual. Como a função ovariana está intimamente relacionada à fisiologia endócrina, o estudo da associação da ovulação com o índice de massa corpórea auxiliará na quantificação da chance de anovulação em pacientes com excesso de peso. Objetivo: Avaliar a associação entre a anovulação à monitorização ultrassonográfica e alterações do peso de pacientes inférteis sem ovários policísticos de um serviço universitário de infertilidade. Métodos: Estudo caso-controle com 228 pacientes atendidas em um centro universitário na cidade de Goiânia. Os fatores de desfecho foram: ovulação ausente (casos= 110) ou presente (controles= 118); e os fatores de exposição: IMC nomal ou acima do normal. A análise de dados foi realizada pelo programa estatístico SPSS 22.0. As diferenças de proporções foram avaliadas por teste Qui-quadrado de Pearson (com correção de Fisher onde necessário) e teste Wilcoxon. O valor de p< 0,05 foi considerado estatisticamente significante. Entre os grupos de pacientes, estavam pareadas as médias das variáveis: idade (1= 32,45 anos ± 4,13; 2= 32,66 anos ± 3,95), menarca (1= 12,56 anos ± 1,75; 2= 12,61 anos ± 1,6), FSH (1= 6,11UI/L ± 1,98; 2= 5,92 UI/L ± 1,61), prolactina (1= 12,17 mcg/L ± 4,04; 2= 12,09 mcg/L ± 3,98), TSH (1= 1,824 mUI/L ± 0,749; 2= 1,775 mU/L ± 0,844). Resultados: As pacientes anovulatórias tiveram chance de terem ciclos irregulares 6,3 vezes a mais que as pacientes ovulatórias. Entre as pacientes ovulatórias, aquelas acima do peso tiveram a ovulação em média no 14,62° dia do ciclo, e as pacientes com IMC normal no 14,21°, sem significância estatística. A média do diâmetro folicular máximo alcançado antes da ovulação foi de 18,62 mm nas pacientes com acima do peso. Entre aquelas com IMC normal, a média foi de 19,10 mm, não havendo diferença estatística. No grupo das pacientes anovulatórias, a média do IMC foi de 25,64 Kg/m² ± 4,24, e no das pacientes ovulatórias, a média do IMC foi de 24,76 Kg/m² ± 3,81. Dentre as pacientes anovulatórias, 51,82% estavam acima do peso, enquanto entre as pacientes ovulatórias, 37,29% estavam nesta mesma categoria de IMC. O Odds Ratio foi de 1,8087, com valor de p significativo (p= 0,0273). Conclusão: Houve associação de anovulação com IMC acima do normal. Entre as pacientes que ovularam, não houve associação do dia da ovulação e do diâmetro máximo do folículo com o IMC. Houve associação de anovulação com o relato de irregularidade do ciclo.

In response to LH surge, the selected dominant follicle undergoes a series of complex events viz., meiotic maturation of the oocyte, terminal differentiation of follicular cells, cumulus expansion and follicular rupture leading to ovulation (release of fertilizable oocyte) and formation of corpus luteum. These complex set of events are mediated by dramatic changes in the temporo-spatial transcriptional regulation of a large number of genes in the preovularory follicle. In the present thesis, attempts have been made to delineate the transcriptional changes occurring in the periovulatory follicle in response to gonadotropin surge in monovulatory species (bonnet monkeys and buffalo cows). Further, attempts have also been made to investigate effects of increased circulating IGF-I and glucose on the periovulatory events. Chapter I provides a review of available literature on regulation and factors influencing various aspects of growth and development of ovarian follicles. Chapter II describes initial studies carried out in the bonnet monkeys to examine expression patterns of various genes considered as markers of ovulation and luteinization in granulosa cells of multiple preovulatory-like follicles before and after exposure to luteinizing dose of hCG. Chapter III describes the standardization and validation of an induced ovulation model system in buffalo cows involving determination of the presence of a large follicle by ultrasonography before administering exogenous PGF2αon day 7 of the cycle to induce luteolysis and administration of hCG 36 h post PGF2αto mimic LH surge-like stimulus. Attempts made to characterize the responsiveness of buffalo cows to a range of exogenous doses of GnRH in terms of LH secretion during summer and winter seasons and determination of the exogenous dose of GnRH necessary to elicit a surge-like increase in circulating LH levels during breeding season in buffalo cows are described in Chapter IV. Chapter V describes the global changes in the gene expression pattern in the periovulatory follicle of buffalo cows before and at various time points after the onset of gonadotropin surges. IGF-I is known to regulate the proliferation and survival of follicular cells and play an important role in the selection of dominant follicle however, its role during the periovulatory events remains to be delineated. Chapter VI describes the effects of increased circulating and intrafollicular IGF-I levels on the periovulatory events. An ongoing study to delineate the effects of transient increase in circulating glucose levels on the periovulatory events are described in Appendix I. Thus, this thesis aims at delineating (i) changes in the gene expression patterns regulating periovulatory events and (ii) effects of increased circulating IGF-I and glucose on the periovulatory events.

Thesis (DMed (Obstetrics and Gynaecology))--Stellenbosch University, 2008. / Chapter 1 presents a literature study on the diagnostic debate of PCOS. The literature study includes a discussion of the recent Rotterdam consensus statement regarding the diagnosis of PCOS. This is followed by a discussion on the essential work-up of the patient presenting with PCOS. Finally, chapter 1 presents a discussion on the complexity of the different variations in women presenting with PCOS. Chapter 2 is a literature review on ovulation induction methods in patients who present with PCOS. This literature study puts special emphasis on the different available methods used for ovulation induction in women with PCOS and the profounding effect weight loss will have in managing these patients. This chapter also addresses the use of newer agents, like aromatase inhibitors (Letrozole), and the current role of each of these agents in ovulation induction protocols. Chapter 3 is a literature overview on the effect of Metformin in Clomiphene-resistant PCOS women. The inclusion criteria of this review was all prospective randomized trials where Metformin was added for ovulation in the Clomiphene-resistant PCOS patient. The data is presented as a metaanalysis. Chapter 4 is a prospective randomise control trial to evaluate the benefit of metformin if added to Clomiphene in a primary ovulation induction protocol in comparison to Clomiphene alone. This chapter also evaluates all factors influencing ovulation outcome. Finally in the discussion section all the recent studies published addressing this topic were reviewed. Chapter 5 is a literature review to evaluate the classification systems for semen parameters and the in vivo fertility potential. This data is also used to establish fertility/subfertility thresholds for semen parameters. This chapter also presents the results of a prospective and retrospective study of the semen analysis of the partners of women with PCOS. We believe that this population presents the best reference group to study the semen profile of the general male population. Chapter 6 is a summary of the results of these studies and serves as an evidence based approach for ovulation induction in women with PCOS.

published_or_final_version / abstract / Obstetrics and Gynaecology / Doctoral / Doctor of Philosophy

Foram realizados cinco experimentos com o objetivo de sincronização do estro e indução da ovulação em tempo fixo em éguas. Experimento I: avaliou a eficácia de um novo protocolo hormonal para a sincronização do estro, sendo realizado durante o período transicional em éguas cujo status reprodutivo era desconhecido. Experimento II: foi delineado para determinar o momento ideal para retirada dispositivo intravaginal de progesterona (DIP), sendo o dispositivo retirado no dia 7, 8 ou 9 do protocolo de tratamento hormonal. Experimento III: testou se a eficiência do protocolo é dependente da fase do ciclo estral da égua e definiu o melhor momento para indução da ovulação. Experimentos IV e V: as éguas foram submetidas ao protocolo completo de sincronização da onda folicular e indução da ovulação em diferentes fases do ciclo estral ou com status reprodutivo conhecido. A hipótese testada foi de que a sincronização do estro e indução da ovulação, com o uso do DIP de 1,44g provoca a supressão do crescimento folicular e através da indução da ovulação, com hCG e GnRH, promove a ovulação dentro de 42 ± 6 horas de no mínimo 75% dos animais. Para isso, os efeitos das prostaglandinas e progestágenos foram avaliados quanto à capacidade de sincronizar a onda de crescimento folicular. Um novo tratamento para induzir a ovulação em tempo fixo foi testado com uma combinação de GnRH e hCG em dois momentos estratégicos (D10 e D12) visando maximizar o número de éguas ovuladas. O protocolo com administração de prostaglandina no D0, D6 e D8 juntamente com a colocação do DIP mantido durante 8 dias (D0 ao D7) demonstrou ser eficaz para suprimir a taxa de crescimento folicular em éguas cíclicas. Nas éguas submetidas a este protocolo as ovulações que ocorreram naturalmente se concentraram entre os dias 10 e 13 do tratamento. Foi testada a eficiência da indução da ovulação no D10 e D12. Na maioria dos animais tratados, o folículo pré-ovulatório foi responsivo à combinação de GnRH e hCG promovendo o sucesso da indução da ovulação. A eficiência do protocolo hormonal testado para sincronização do estro e da ovulação foi de 76,73%, sustentando a hipótese deste estudo. Novos estudos devem ser realizados em um maior número de animais para possíveis adequações na terapia hormonal e verificação do resultado em um grande número experimental de animais. / Five experiments were conducted with the objective of estrus synchronization and fixed time ovulation induction in mares. Experiment I: evaluated the efficacy of a new hormonal protocol for estrus synchronization in mares whose reproductive status was unknown during the transitional period. Experiment II: was designed to determine the best time to remove the P4 intravaginal device (PID). The device was removed on day 7, 8 or 9 of the hormonal treatment protocol. Experiment III: tested if protocol efficiency depends on the stage of mares estrus cycle and indicated the best time for hormonal induction of ovulation. Experiments IV and V: mares were submitted to the full protocol of follicular wave synchronization and ovulation induction at different stages of estrus cycle or at known reproductive status. The tested hypothesis was that the estrus synchronization and induction of ovulation, using an PID of 1.44g, causes suppression of follicular growth, and ovulation induction using hCG and GnRH promote ovulation within 42 ± 6 hours of at least 75% of treated animals. The effect of prostaglandin and progestagens at specific times were evaluated for the ability to synchronize follicular wave. A new treatment to induce fixed time ovulation was tested with GnRH and hCG combination in two strategic moments (D10 and D12) to maximize the number of ovulated mares. Administration of prostaglandin at D0, D6 and D8 together with PID maintained for 8 days (D0 to D7) proved to be effective to suppress follicular growth during reproductive period. In mares submitted to this protocol, ovulation occurred naturally and concentrated between D10 and D13. The ovulation induction efficiency was tested at D10 and D12. Most of the animals had preovulatory follicle responsiveness to GnRH and hCG, promoting the success of ovulation induction. The efficiency of the tested synchronization of estrus and ovulation induction protocol was 76.73% and supported the hypothesis of this study. Further studies should be performed on a larger number of animals for possible adjustments in hormonal therapy and verification of the result in a large number of animals.

No description available.

Bibliography: leaves [124-153]

Bibliography: leaves [124-153] / x, 123 leaves : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Obstetrics and Gynaecology, 2001