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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.
71

Pubertätsentwicklung bei Kindern und Jugendlichen und Assoziationen zum sozioökonomischen Status: Ergebnisse der LIFE Child Studie

Oelkers, Lea Katharina Jeanette 15 June 2022 (has links)
Die vorliegende Arbeit liefert Auswertungen aktueller Pubertätsdaten und neue Erkenntnisse zum Einfluss des SES auf die Pubertät. Wir konnten zeigen, dass ein niedriger SES vor allem bei übergewichtigen/adipösen Mädchen mit einer früheren und länger andauernden Pubertät assoziiert ist. Im Diskurs über soziale Ungleichheiten und den damit einhergehenden Gesundheitsrisiken betont die vorliegende Arbeit die Wichtigkeit, die Chancengleichheit von Kindern und Jugendlichen zu verbessern.:I Abkürzungsverzeichnis 4 1 Einleitung 5 1.1 Hintergrund 5 1.2 Die Pubertät: Weg zur reproduktiven Reife 6 1.2.1 Physiologie der Pubertätsentwicklung 6 1.2.2 Methodik zur Erfassung der Pubertätsparameter 8 1.3 Früher Pubertätsbeginn: Trends, Risiken und Einflussfaktoren 8 1.3.1 Einfluss des BMI auf den Pubertätsbeginn 9 1.3.2 Sozialer Status und Pubertätsentwicklung 10 1.3.2.1 Sozialstatus und Gesundheit 10 1.3.2.2 Sozialstatus und frühe Pubertät 11 1.3.2.3 Methodik zur Erfassung des sozialen Status 14 1.4 Rückschlüsse zur Vorgehensweise 14 1.4.1 Fragestellungen/Ziele 14 1.4.2 Studiendesign 15 2 Publikationsmanuskript 16 3 Zusammenfassung der Arbeit 26 4 References 29 II Anhang 41 III Darstellung des eigenen Beitrags 42 IV Erklärung über die eigenständige Abfassung der Arbeit 43 VI Publikation 44 VII Danksagung 45
72

Effect of Oral Contraceptives on the Rat Brain and Pituitary Opioid Peptides

Tejwani, Gopi A., Vaswani, Kuldeep K., Barbacci, Josephine C. 01 January 1985 (has links)
This study was designed to explore the hormonal regulation of CNS opioid peptide levels in female Sprague Dawley rats. Forty-eight animals were divided into 2 equal groups for acute and chronic studies. Each group was further divided into 4 subgroups, each containing 6 animals. Each rat in the control group received an inert pill (in 0.25 ml corn oil daily by gavage); the second group, 15 μg norethindrone (NE, a potent progestin present in the oral contraceptive Micronor®); the third group, 15 μg NE and 1 μg ethinyl estradiol, EE2 (present in the oral contraceptive Modicon®) and the fourth group, 10 times the dose of the third group. Rats were treated either acutely for 5 days or chronically for 7 weeks. Opioid peptides were estimated by radioimmunoassay. Acute administration of 150 μg NE + 10 μg EE2 decreased the levels of methionine-enkephalin (ME), leucine-enkephalin (LE), dynorphin (DYN) and β-endorphin like immunoreactivity (β-EI) by about 50% in the pituitary. The same dose on chronic administration also decreased DYN, but increased the levels of ME and LE in the pituitary by 331 and 69%, respectively. In the hypothalamus, chronic administration of NE + EE2 increased the level of ME (155%) and LE (87%) as well as of DYN (97%). In the striatum, the levels of LE (33%) and DYN (115%) were elevated during chronic administration. It is concluded that the acute administration of NE + EE2, in general, reduces the levels of ME, LE, DYN and β-EI. The extent of this decrease is about the same in the pituitary, hypothalamus and striatum. Chronic administration of these hormones, however, results in a reversal of this decrease (except for β-EI) and actually can increase the levels of ME, LE and DYN in all three tissues.
73

Puberdade e a vida útil reprodutiva das fêmeas suínas / Puberty and lifetime reproduction gilts

Santo, Tacia Antunes Del 06 December 2012 (has links)
O presente estudo teve como objetivo verificar o efeito do uso de gonadotrofinas exógenas na indução do estro à puberdade em marrãs, e \"flushing\" alimentar no ciclo estral que antecede a primeira inseminação artificial na vida útil reprodutiva. O experimento foi realizado na Granja Barreiro (Suinocultura Rosetto) Cerqueira César/SP. Foram utilizadas 96 fêmeas da puberdade ao 1° parto, e 68 fêmeas selecionadas das 96 com ordem de parto do primeiro ao sexto para a avaliação associativa com a vida útil reprodutiva. O delineamento experimental foi inteiramente casualizado em um fatorial 2x2 sendo um fator a combinação hormonal H,( 600 UI de eCG e após 72 horas, 2,5 mg de LH porcino) (H) e o estímulo do macho (M). O fator \"flushing\" alimentar correspondeu ao esquema com restrição (R) e o adotado na granja (G). Os tratamentos foram: HR - hormônio e \"flushing\"; HG - hormônio e esquema alimentar da granja; MR - macho e \"flushing\" e MG - macho e esquema alimentar da granja. As informações foram obtidas a partir do banco de dados existente na propriedade onde o experimento foi realizado. As variáveis análisadas foram: número de estros pós-indução, total de nascidos (TN), nascidos vivos (NV), natimortos (NT), mumificados (MM) e intervalo entre partos (ITP). Cinco dias após a aplicação do tratamento hormonal, 31,37% (H) das fêmeas manifestaram características de estro quando comparado ao tratamento M, onde 11,62% apresentaram estro. O tratamento H mostrou maior sincronismo nas manifestações dos estros, diferente do tratamento M que apresentou maior dispersão ao longo dos ciclos. Não houve diferença estatística nas características de primeiro parto entre os tratamentos hormônio e \"flushing\", tanto quanto nas suas interações (P>0,05). Não houve influência dos tratamentos na produtividade dos animais nas diferentes parições (P>0,05). Portanto, apesar do maior sincronismo apresentado pela combinação hormonal em comparação com o estímulo natural somente pela presença do macho, não houve diferenças quanto à produtividade associativa do primeiro parto e demais partos nas características avaliadas. / The present study objective to verify the effect of the use of exogenous gonadotropins in oestrus induction of puberty in gilts, and \"flushing\" feed the estrous cycle before the first artificial insemination in lifetime reproductive. The experiment was conducted at the Granja Barreiro (Swine Rosetto) - Cerqueira César / SP. A total of 96 females from puberty to the 1st delivery, and 68 of the 96 selected females with birth order from first to sixth for assessing association with lifetime reproductive. The experimental design was completely randomized in a 2x2 factorial being a combination hormonal factor H (600 IU eCG and after 72 hours, 2.5 mg porcine LH) (H) and the stimulation of the male (M). The factor \"flushing\" food matched the schema constraint (R) and adopted on the farm (G). The treatments were: HR - hormone and \"flushing\"; HG - hormone regimen and feed the farm; MR - male and \"flushing\" and MG - male and feed the farm scheme. The information was obtained from the existing database on the property where the experiment was conducted. The variables analyzed were: number of post-estrus induction, total born (TN) live births (NV), stillbirths (NT), mummified (MM) and calving interval (ITP). Five days after application of the treatment, 31,37% (H) of estrus females showed characteristics when compared to treatment M, where 11,62% showed estrous. The H treatment showed greater synchronization of estrus in the demonstrations, unlike the M treatment with the highest dispersion along the cycles. There was no statistical difference in the characteristics of first birth among hormone treatments and \"flushing\" as well as their interactions (P>0.05). No influence of the treatments on the productivity of animals in different parities (P>0.05). Therefore, despite the higher timing presented by combination hormonal stimulation compared with only natural for the presence of males, there were no differences in yield associative first birth and other birth characteristics evaluated.
74

Dijagnoza reproduktivnog statusa nazimica na osnovu ovarijalnog i estrusnog reagovanja, posle tretmana gonadotropnim, luteolitičkim i progestagenim hormonskim preparatima / Diagnosis of gilts reproductive status based on ovarian and estrual reactions, after treatment by gonadotropic, luteolitic and progestagen hormonal preparations

Bošnjak Darko 24 May 2014 (has links)
<p>Determinacija reproduktivnog statusa priplodnih nazimica je važan faktor u tehnologiji njihovog odgoja i reproduktivnog iskori&scaron;tavanja. Zbog toga je, u intenzivnoj proizvodnji svinja, potrebna primena efikasnih metoda dijagnoze reproduktivnog statusa nazimica. Klasična metoda testiranja pojave estrusa, kontaktom nazimica sa polno zrelim nerastom nije dovoljno precizna. Pokazalo se, naime, da se, zbog nepreciznosti ove metode, oko 30 do 40% priplodnih nazimica izlučuje iz priploda, sa dijagnozom &bdquo;prolongirani preinseminacioni anestrus&ldquo;, iako su ove nazimice uspostavile cikličnu ovarijalnu aktivnost. Ovo ima za posledicu značajne zootehnolo&scaron;ke i ekonomske gubitke. Metoda real-time ultrazvučne dijagnoze reproduktivnog statusa je precizna, ali je skupa i nepraktična za masovnu primenu. Zbog toga je cilj ovog rada bio da se ispita mogućnost dijagnoze reproduktivnog statusa nazimica, na onsovu ovarijalnog i estrusnog reagovanja posle tretmana gonadotropnim, luteolitičkim i progestagenim hormonskim preparatima. Dobijeni rezultati pokazuju da postoji vrlo specifično ovarijalno i estrusno reagovanje polno nezrelih i polno zrelih nazimica, zavisno od primenjenog hormonskog tretmana. Rezultati primene luteolitičkih tretmana (PGF2&alpha;), pokazuju da ovaj tretman nije dovoljno precizan za dijagnozu reproduktivnog statusa nazimica. Tretman gonadotropnim hormonima (eCG i hCG) daje samo delimično precizne rezultate dijagnoze reproduktivnog statusa. Naime, polno nezrele nazimice reaguju dobrom sinhronizacijom estrusa, unutar prosečno 4 dana posle injekcije eCG. Međutim, trajanje intervala od injekcije eCG do pojave estrusa značajno varira, između 4 i 25 dana, kod polno zrelih nazimica. Vrlo precizna diferencijalna dijagnoza reproduktivnog statusa nazimica se postiže tretmanom sa progestagenim preparatima (Altrenogest, Regumate&reg;). Polno nezrele nazimice ne reaguju sinhronizovanom ovulacijom i pojavom estrusa, posle tretmana progestagenim preparatom. Polno zrele nazimice, međutim, reaguju vrlo viskim stepeno sinhronizovane ovulacije i pojave estrusa, posle progestagenog tretmana. Dobijeni rezultati predstavljaju doprinos boljem poznavanju ovarijalnog i estrusnog reagovanja nazimica, posle tretmana egzogenim gonadotropinima, luteoliticima i progestagenima. Osim toga, ovi rezultati pružaju mogućnost precizne dijagnoze reproduktivnog statusa nazimimica u proizvodnim uslovima. Na taj način je moguće formulisati efikasniju tehnologiju reproduktivne eksploatacije nazimica i, time, povećati efikasnost intenzivne proizvodnje svinja.</p> / <p>Determination of the replacement gilts reproductive status is an important factor of gilts reproductive utilization efficiency. Therefore, the intensive pig production, require the application of effective methods of gilts diagnosis reproductive status. Classical method for estrus manifestation testing, by gilts contact with sexually mature boar is not precise enough. It has been proved that, due to the inaccuracy of this method, about 30 to 40% gilts are culled from the breeding, with a diagnosis of &quot;prolonged preinsemination anestrus,&quot; although these gilts was established cyclical ovarian activity. This results in significant zootechnical and economical losses. Method of real-time ultrasound diagnosis of reproductive status was accurate, but it is expensive and impractical in productive conditions. Therefore, the aim of this study was to investigate the possibility of gilts reproductive status diagnose, based on ovarian and estrous response after treatment with gonadotropin, luteolytic and progestogen hormonal preparations. Obtained results show that there is a very specific ovarian and estrous response of sexually immature and sexually mature gilts, depending on the applied hormonal treatment. Results of the luteolytic (PGF2&alpha;) treatment application, show that this treatment is not specific enough for the gilts reproductive status diagnosis. Treatment with gonadotropins (hCG and ECG) gives only a partial accurate diagnosis of gilts reproductive status. The sexually immature gilts respond with high level of estrus synchronization, within average 4 days after eCG injection. However, the interval from eCG injection to estrus manifestation varied between 4 and 25 days, in sexually mature gilts. Very accurate differential diagnosis of gilts reproductive status was achieved by treatment with progestogen preparations. Sexually immature gilts was not respond by synchronized estrus and ovulation, after treatment with progestogen preparation. Buth, sexually mature gilts respond with highly synchronized ovulation and estrus, within average 5 days after progestagenog treatment. The obtained results contribute to a better understanding of gilts ovarian and estrous responses to exogenous gonadotropins, luteolytics and progestagens treatment. In addition, these results provide an accurate ability for gilts reproductive status diagnosis in farms production conditions. On this way it is possible to formulate a more efficient technology of gilts reproductive exploitation and,thus, increase the efficiency of intensive pig production.</p>
75

Estudo do desempenho reprodutivo e perfil metabólico de fêmeas suínas primíparas submetidas a manejos nutricionais diferenciados aliados ao emprego de gonadotrofinas exógenas / Evaluation of reproductive performance and metabolic profile of primiparous sows submitted to different nutritional managements and exogenous gonadotropins

Eckhardt, Octávio Henrique Orlovsky 17 December 2009 (has links)
O presente estudo buscou averiguar a relação de manejos nutricionais diferenciados no terço final de gestação associados ou não ao emprego de gonadotrofinas exógenas no pós-desmame com a manifestação da redução da segunda leitegada em fêmeas suínas. O experimento foi realizado no Laboratório de Pesquisa em Suínos (VNP-FMVZ-USP) Pirassununga/SP. Foram utilizadas 23 marrãs prenhes, sendo empregado o delineamento experimental inteiramente casualizado em arranjo fatorial de tratamentos, sendo um fator o manejo nutricional a partir de 75 &plusmn; 1,74 dias de gestação, fornecendo-se 2,9 kg/dia de ração de pré-lactação (P; 3.203 kcal EM/kg, 17,25% PB) ou 2,5 kg/dia de ração de gestação (G; 2.930 kcal EM/kg, 16,43% PB) e o segundo a aplicação hormonal - 600UI de eCG e, após 72 horas, 2,5mg de LH porcino - no dia do desmame (H) ou não (C). Semanalmente, entre o 82º dia de gestação e o dia do desmame, se averiguou o peso vivo dos animais e colheram-se amostras de sangue para avaliação de parâmetros de bioquímica sanguínea, sendo as fêmeas abatidas 4,55 ± 0,92 dias após a inseminação artificial pós-desmame para colheita e avaliação de embriões. Fêmeas do tratamento P apresentaram maior ganho de peso diário (p<0,050) em três das cinco semanas do terço final de gestação avaliadas, obtendo maior ganho de peso geral entre o 75º dia de gestação e a avaliação pré parto (p<0,001). Na fase de lactação, o tratamento P apresentou maior perda de peso na 1ª (p=0,038) e 3ª (p=0,061) semanas. Não foram observadas diferenças no tocante ao consumo de ração na lactação, desempenho da leitegada ou retorno a atividade reprodutiva pós-desmame. Na avaliação dos embriões, foi observada interação entre os fatores para a variável porcentagem de estruturas fecundadas (p=0,051), obtendo-se valores de 98,55%, 78,97%, 96,88% e 99,09% para GC, GH, PC e PH, respectivamente. Tal resultado sugere uma participação do estado metabólico sobre a resposta à hormonioterapia, devendo estes mecanismos serem objeto de estudos mais específicos. Animais submetidos ao protocolo hormonal apresentaram maior porcentagem de embriões na fase de mórula (p=0,050). As alterações de qualidade embrionária associadas à utilização de gonadotrofinas exógenas podem estar ligadas a mudanças no desenvolvimento folicular, levando a ovulação de oócitos de qualidade inferior e desenvolvimento alterado dos futuros embriões. Animais alimentados com ração de pré-lactação apresentaram maiores níveis de colesterol total e suas frações (HDL, LDL e VLDL) na fase de gestação, ligados à maior ingestão de nutrientes e substratos energéticos, e maiores concentrações de ácidos graxos não esterificados (AGNE) no momento do parto e durante a lactação, associados à maior mobilização de reservas corporais. No contexto experimental apresentado, pode-se inferir que o catabolismo na fase de lactação, quando moderado e acompanhado de maiores reservas no momento do parto, não interferiu significativamente no desempenho reprodutivo pós-desmame. A indução de quadros mais severos de catabolismo lactacional pode contribuir para o esclarecimento dos reflexos deste estado metabólico sobre a atividade reprodutiva de fêmeas suínas. / The present study evaluated the relationship between different nutritional managements in the last third of gestation associated or not with exogenous gonadotropins hormonal protocol at weaning and the manifestation of second litter reduction in female swine. The experiment was carried out in the Laboratory of Swine Research (VNP-FMVZ-USP) Pirassununga/SP. Twenty three (23) pregnant gilts were used in a completely random factorial design, with one factor being the nutritional management from 75 &plusmn; 1,74 days of gestation onward, feeding animals with 2,9 kg/day of a pre-lactation diet (P; 3.203 kcal ME/kg, 17,25% CP) or 2,5 kg/day of a gestation diet (G; 2.930 kcal ME/kg, 16,43% CP), and the second factor being the hormonal protocol 600IU of eCG and, after 72 hours, 2,5mg of porcine LH administration (H) or not (C) at weaning. Weekly, from day 82 of gestation until weaning, body weight were measured and blood samples were collected for determinations of serum bioquimical parameters. Females were slaughtered 4,55 ± 0,92 days after artificial insemination for embryo collection and evaluation. Animals in the P treatment showed higher body weight gains (p<0,050) un three of the five weeks evaluated in the late gestation, obtaining higher overall weight gain between days 75 of gestation and the pre partum evaluation (p<0,001). In the lactation period, treatment P showed higher weight losses in the 1st(p=0,038) and 3rd(p=0,061) weeks. No differences in feed consumption during lactation, litter performance and post weaning return to reproductive activity were observed. In the embryo evaluation, an interaction between factors was observed for the percentage of fecundated structures (p=0,051), with values of 98,55%, 78,97%, 96,88% e 99,09% for GC, GH, PC e PH, respectively. Such result indicates a effect of the metabolic state on the response to the hormonal therapy, with the need of further studying the mechanisms involved. Animals submitted to the hormonal protocol showed a higher percentage of embryos in the morula stage (p=0,050). Changes in embryo quality associated with the administration of exogenous gonadotropins might be linked to shifts in follicular growth, leading to the ovulation of oocites of lower quality and altered future embryo development. Females fed the pre-lactation diet had higher total cholesterol and fractions (HDL, LDL, VLDL) in the gestation period, which is linked to the higher consumption of energy yielding substances, and higher concentrations of non-sterified fatty acids (NEFA) during farrowing and lactation, which are related to more severe fat mobilization. In the context of the present experiment, the catabolism during lactation, when moderate and accompanied by higher body reserves at farrowing, did not significantly interfere with the post-weaning reproductive performance. The induction of more severe catabolic states might contribute to enhance our knowledge on the effects of this metabolic state on the reproductive outcome of sows.
76

Estudo do desempenho reprodutivo e perfil metabólico de fêmeas suínas primíparas submetidas a manejos nutricionais diferenciados aliados ao emprego de gonadotrofinas exógenas / Evaluation of reproductive performance and metabolic profile of primiparous sows submitted to different nutritional managements and exogenous gonadotropins

Octávio Henrique Orlovsky Eckhardt 17 December 2009 (has links)
O presente estudo buscou averiguar a relação de manejos nutricionais diferenciados no terço final de gestação associados ou não ao emprego de gonadotrofinas exógenas no pós-desmame com a manifestação da redução da segunda leitegada em fêmeas suínas. O experimento foi realizado no Laboratório de Pesquisa em Suínos (VNP-FMVZ-USP) Pirassununga/SP. Foram utilizadas 23 marrãs prenhes, sendo empregado o delineamento experimental inteiramente casualizado em arranjo fatorial de tratamentos, sendo um fator o manejo nutricional a partir de 75 &plusmn; 1,74 dias de gestação, fornecendo-se 2,9 kg/dia de ração de pré-lactação (P; 3.203 kcal EM/kg, 17,25% PB) ou 2,5 kg/dia de ração de gestação (G; 2.930 kcal EM/kg, 16,43% PB) e o segundo a aplicação hormonal - 600UI de eCG e, após 72 horas, 2,5mg de LH porcino - no dia do desmame (H) ou não (C). Semanalmente, entre o 82º dia de gestação e o dia do desmame, se averiguou o peso vivo dos animais e colheram-se amostras de sangue para avaliação de parâmetros de bioquímica sanguínea, sendo as fêmeas abatidas 4,55 ± 0,92 dias após a inseminação artificial pós-desmame para colheita e avaliação de embriões. Fêmeas do tratamento P apresentaram maior ganho de peso diário (p<0,050) em três das cinco semanas do terço final de gestação avaliadas, obtendo maior ganho de peso geral entre o 75º dia de gestação e a avaliação pré parto (p<0,001). Na fase de lactação, o tratamento P apresentou maior perda de peso na 1ª (p=0,038) e 3ª (p=0,061) semanas. Não foram observadas diferenças no tocante ao consumo de ração na lactação, desempenho da leitegada ou retorno a atividade reprodutiva pós-desmame. Na avaliação dos embriões, foi observada interação entre os fatores para a variável porcentagem de estruturas fecundadas (p=0,051), obtendo-se valores de 98,55%, 78,97%, 96,88% e 99,09% para GC, GH, PC e PH, respectivamente. Tal resultado sugere uma participação do estado metabólico sobre a resposta à hormonioterapia, devendo estes mecanismos serem objeto de estudos mais específicos. Animais submetidos ao protocolo hormonal apresentaram maior porcentagem de embriões na fase de mórula (p=0,050). As alterações de qualidade embrionária associadas à utilização de gonadotrofinas exógenas podem estar ligadas a mudanças no desenvolvimento folicular, levando a ovulação de oócitos de qualidade inferior e desenvolvimento alterado dos futuros embriões. Animais alimentados com ração de pré-lactação apresentaram maiores níveis de colesterol total e suas frações (HDL, LDL e VLDL) na fase de gestação, ligados à maior ingestão de nutrientes e substratos energéticos, e maiores concentrações de ácidos graxos não esterificados (AGNE) no momento do parto e durante a lactação, associados à maior mobilização de reservas corporais. No contexto experimental apresentado, pode-se inferir que o catabolismo na fase de lactação, quando moderado e acompanhado de maiores reservas no momento do parto, não interferiu significativamente no desempenho reprodutivo pós-desmame. A indução de quadros mais severos de catabolismo lactacional pode contribuir para o esclarecimento dos reflexos deste estado metabólico sobre a atividade reprodutiva de fêmeas suínas. / The present study evaluated the relationship between different nutritional managements in the last third of gestation associated or not with exogenous gonadotropins hormonal protocol at weaning and the manifestation of second litter reduction in female swine. The experiment was carried out in the Laboratory of Swine Research (VNP-FMVZ-USP) Pirassununga/SP. Twenty three (23) pregnant gilts were used in a completely random factorial design, with one factor being the nutritional management from 75 &plusmn; 1,74 days of gestation onward, feeding animals with 2,9 kg/day of a pre-lactation diet (P; 3.203 kcal ME/kg, 17,25% CP) or 2,5 kg/day of a gestation diet (G; 2.930 kcal ME/kg, 16,43% CP), and the second factor being the hormonal protocol 600IU of eCG and, after 72 hours, 2,5mg of porcine LH administration (H) or not (C) at weaning. Weekly, from day 82 of gestation until weaning, body weight were measured and blood samples were collected for determinations of serum bioquimical parameters. Females were slaughtered 4,55 ± 0,92 days after artificial insemination for embryo collection and evaluation. Animals in the P treatment showed higher body weight gains (p<0,050) un three of the five weeks evaluated in the late gestation, obtaining higher overall weight gain between days 75 of gestation and the pre partum evaluation (p<0,001). In the lactation period, treatment P showed higher weight losses in the 1st(p=0,038) and 3rd(p=0,061) weeks. No differences in feed consumption during lactation, litter performance and post weaning return to reproductive activity were observed. In the embryo evaluation, an interaction between factors was observed for the percentage of fecundated structures (p=0,051), with values of 98,55%, 78,97%, 96,88% e 99,09% for GC, GH, PC e PH, respectively. Such result indicates a effect of the metabolic state on the response to the hormonal therapy, with the need of further studying the mechanisms involved. Animals submitted to the hormonal protocol showed a higher percentage of embryos in the morula stage (p=0,050). Changes in embryo quality associated with the administration of exogenous gonadotropins might be linked to shifts in follicular growth, leading to the ovulation of oocites of lower quality and altered future embryo development. Females fed the pre-lactation diet had higher total cholesterol and fractions (HDL, LDL, VLDL) in the gestation period, which is linked to the higher consumption of energy yielding substances, and higher concentrations of non-sterified fatty acids (NEFA) during farrowing and lactation, which are related to more severe fat mobilization. In the context of the present experiment, the catabolism during lactation, when moderate and accompanied by higher body reserves at farrowing, did not significantly interfere with the post-weaning reproductive performance. The induction of more severe catabolic states might contribute to enhance our knowledge on the effects of this metabolic state on the reproductive outcome of sows.
77

Puberdade e a vida útil reprodutiva das fêmeas suínas / Puberty and lifetime reproduction gilts

Tacia Antunes Del Santo 06 December 2012 (has links)
O presente estudo teve como objetivo verificar o efeito do uso de gonadotrofinas exógenas na indução do estro à puberdade em marrãs, e \"flushing\" alimentar no ciclo estral que antecede a primeira inseminação artificial na vida útil reprodutiva. O experimento foi realizado na Granja Barreiro (Suinocultura Rosetto) Cerqueira César/SP. Foram utilizadas 96 fêmeas da puberdade ao 1° parto, e 68 fêmeas selecionadas das 96 com ordem de parto do primeiro ao sexto para a avaliação associativa com a vida útil reprodutiva. O delineamento experimental foi inteiramente casualizado em um fatorial 2x2 sendo um fator a combinação hormonal H,( 600 UI de eCG e após 72 horas, 2,5 mg de LH porcino) (H) e o estímulo do macho (M). O fator \"flushing\" alimentar correspondeu ao esquema com restrição (R) e o adotado na granja (G). Os tratamentos foram: HR - hormônio e \"flushing\"; HG - hormônio e esquema alimentar da granja; MR - macho e \"flushing\" e MG - macho e esquema alimentar da granja. As informações foram obtidas a partir do banco de dados existente na propriedade onde o experimento foi realizado. As variáveis análisadas foram: número de estros pós-indução, total de nascidos (TN), nascidos vivos (NV), natimortos (NT), mumificados (MM) e intervalo entre partos (ITP). Cinco dias após a aplicação do tratamento hormonal, 31,37% (H) das fêmeas manifestaram características de estro quando comparado ao tratamento M, onde 11,62% apresentaram estro. O tratamento H mostrou maior sincronismo nas manifestações dos estros, diferente do tratamento M que apresentou maior dispersão ao longo dos ciclos. Não houve diferença estatística nas características de primeiro parto entre os tratamentos hormônio e \"flushing\", tanto quanto nas suas interações (P>0,05). Não houve influência dos tratamentos na produtividade dos animais nas diferentes parições (P>0,05). Portanto, apesar do maior sincronismo apresentado pela combinação hormonal em comparação com o estímulo natural somente pela presença do macho, não houve diferenças quanto à produtividade associativa do primeiro parto e demais partos nas características avaliadas. / The present study objective to verify the effect of the use of exogenous gonadotropins in oestrus induction of puberty in gilts, and \"flushing\" feed the estrous cycle before the first artificial insemination in lifetime reproductive. The experiment was conducted at the Granja Barreiro (Swine Rosetto) - Cerqueira César / SP. A total of 96 females from puberty to the 1st delivery, and 68 of the 96 selected females with birth order from first to sixth for assessing association with lifetime reproductive. The experimental design was completely randomized in a 2x2 factorial being a combination hormonal factor H (600 IU eCG and after 72 hours, 2.5 mg porcine LH) (H) and the stimulation of the male (M). The factor \"flushing\" food matched the schema constraint (R) and adopted on the farm (G). The treatments were: HR - hormone and \"flushing\"; HG - hormone regimen and feed the farm; MR - male and \"flushing\" and MG - male and feed the farm scheme. The information was obtained from the existing database on the property where the experiment was conducted. The variables analyzed were: number of post-estrus induction, total born (TN) live births (NV), stillbirths (NT), mummified (MM) and calving interval (ITP). Five days after application of the treatment, 31,37% (H) of estrus females showed characteristics when compared to treatment M, where 11,62% showed estrous. The H treatment showed greater synchronization of estrus in the demonstrations, unlike the M treatment with the highest dispersion along the cycles. There was no statistical difference in the characteristics of first birth among hormone treatments and \"flushing\" as well as their interactions (P>0.05). No influence of the treatments on the productivity of animals in different parities (P>0.05). Therefore, despite the higher timing presented by combination hormonal stimulation compared with only natural for the presence of males, there were no differences in yield associative first birth and other birth characteristics evaluated.
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A morphological investigation of the effects of pregnant mare serum gonadotrophin on oocyte maturation, fertilization and embryonic development in rats

Britton, Ann Patricia January 1991 (has links)
A delicate balance of steroid and gonadotrophic hormones is essential for intrafollicular oocyte maturation and successful fertilization and embryonic development. Previous studies have demonstrated that a superovulatory dose of pregnant mare serum gonadotrophin (PMSG) has excessive gonadotrophic activity and alters intrafol1icular steroid hormone levels. In a series of four experiments, the morphology of oocytes and embryos retrieved from immature rats, treated with either a low or high dose of PMSG, and mature, cycling rats was compared to determine whether a superovulatory dose of PMSG has an adverse effect on oocyte maturation and subsequent fertilization and embryonic development in immature rats. Morphological criteria for the assessment of intraoviductal oocyte aging were established in the first experiment. During intraoviductal aging, progressive morphological changes directed by the intrinsic developmental program of the oocyte were observed. Further alterations in morphology were attributed to abnormalities of cytoskeletal function. In the second experiment, no difference in morphology was observed between oocytes retrieved from immature rats treated with either 4 or 40 IU PMSG. When compared with mature rats, changes attributable to cytoskeletal instability were observed in aged oocytes from immature rats treated with both doses of PMSG. This was concluded to be a manifestation of altered intrafollicular oocyte maturation as a result of the administration of exogenous gonadotrophin. In the third and fourth experiments, delayed fertilization and a significant reduction in fertilization rate were observed in superovulated, immature rats. The major cause of fertilization failure was determined to be intraoviductal oocyte aging. A significant increase in abnormal embryos was observed as a result of parthenogenetic activation of the aged oocytes. Abnormal, fertilized embryos retrieved from the superovulated group were concluded to be the manifestation of delayed fertilization. In conclusion, the major effect of a superovulatory dose of PMSG on oocyte fertilizability and embryonic development was intraoviductal oocyte aging and delayed fertilization. Changes attributed to altered intrafol1icular maturation were manifested during oocyte aging in immature rats treated with either the low or high dose of PMSG. / Medicine, Faculty of / Obstetrics and Gynaecology, Department of / Graduate
79

Un nouveau rôle de la voie Hippo dans la synthèse des gonadotrophines

Lalonde-Larue, Ariane 04 1900 (has links)
L’hypophyse est une glande endocrine responsable de la régulation de nombreux processus physiologiques, notamment la reproduction, par la sécrétion des gonadotrophines, la FSH et la LH. Ces hormones sont des glycoprotéines dimériques composées d'une sous-unité α commune (CGA) et de sous-unités β uniques (LHβ et FSHβ), qui confèrent une spécificité biologique. La synthèse de la FSH et la LH au niveau des cellules gonadotropes dépend entre autres de l’expression génique de gènes clés tels que Fshb et Lhb, dont la transcription est régulée par différents facteurs. La GnRH, produite par l’hypothalamus, en est la principale régulatrice, mais d’autres facteurs tels que les activines, qui signalent via des protéines nommées SMAD, participent à cette régulation. L'activité de la voie SMAD peut être modifiée par des interactions avec la voie Hippo dans plusieurs tissus et types de cellules, mais l’implication de la voie Hippo dans la régulation de la synthèse des gonadotrophines n'a jamais été investiguée. La voie de signalisation Hippo est une cascade de kinases qui contrôle l'activité des corégulateurs transcriptionnels fonctionnellement redondants YAP et TAZ. Afin d’élucider les rôles de YAP/TAZ dans la synthèse et la sécrétion de gonadotrophines, nous avons utilisé une approche de ciblage génique conditionnel (cKO) afin de causer la délétion de Yap/Taz spécifiquement dans les cellules gonadotropes. Nous avons constaté que cette délétion entraînait une augmentation de la sécrétion de la FSH et la LH chez les souris mâles, ainsi qu'une légère augmentation de la densité des spermatozoïdes. Les souris femelles cKO avaient des taux plus élevés de la LH sérique (mais pas de la FSH), qui étaient associés à un phénotype d'hyperfertilité caractérisé par des taux d'ovulation plus élevés et des portées plus nombreuses. Étonnamment, la perte de YAP/TAZ dans les gonadotropes n'a pas semblé affecter les gènes clés liés à la synthèse des gonadotrophines, mais la sécrétion de la LH basale et induite par la GnRH a augmenté dans les cellules hypophysaires de souris cKO cultivées in vitro. Les mêmes résultats ont été obtenus dans la lignée LβT2, une lignée de cellules gonadotropes immortalisées lorsque l’action de YAP/TAZ fut inhibée pharmacologiquement. Ensemble, ces résultats indiquent que YAP/TAZ suppriment la sécrétion des gonadotrophines (en particulier de la LH) dans les cellules gonadotropes et révèlent donc un tout nouveau rôle de la voie Hippo dans la reproduction chez mammifères. / The pituitary gland is responsible for regulating many physiological processes. Through the secretion of gonadotropins FSH and LH, the pituitary is considered a major regulator of reproduction. These hormones are dimeric glycoproteins composed of a common α subunit (CGA) and unique β subunits (LHβ and FSHβ), which confer biological specificity. The synthesis of FSH and LH at pituitary gonadotrope cells depends mostly on the expression of key genes as Fshb and Lhb. GnRH, produced by the hypothalamus, is the primary regulator, but other factors such as activins, which signal through proteins called SMADs, participate in this regulation. The activity of the SMAD pathway can be altered by crosstalk with the Hippo pathway in several tissues and cell types, but whether the Hippo pathway is involved in regulating gonadotropin synthesis has not been determined. The core Hippo signaling pathway consists of a kinase cascade that regulates the activity of the functionally redundant transcriptional co-regulators YAP and TAZ. To elucidate the roles of YAP/TAZ in gonadotropin synthesis and secretion, we decided to use a conditional gene targeting approach (cKO), which allowed us to promote the depletion of Yap/Taz specifically in the gonadotrope cells. Such conditional deletion resulted in increased circulating levels of FSH and LH in male mice, along with a slight sperm density increase. cKO female mice had augmented circulating LH (but not FSH) levels, which were associated with a hyperfertility phenotype characterized by higher ovulation rates and larger litter sizes. Surprisingly, the loss of YAP/TAZ in gonadotropes did not appear to affect key gonadotropin synthesis-related genes, but both basal and GnRH-induced LH secretion was increased in pituitary cells from cKO mice cultured in vitro. Similar results were obtained using pharmacological inhibition of YAP/TAZ in LβT2 gonadotrope-like cells in vitro. Together, these results indicate that YAP/TAZ suppress gonadotropin release (particularly LH) in gonadotrope cells and reveal a completely novel role of the Hippo pathway in mammalian reproduction.
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Perfil dos esteroides gonadais e expressão dos hormônios folículo estimulante (FSH) e luteinizante (LH) durante a inversão sexual de Epinephelus marginatus (Teleostei: Serranidae), hermafrodita protogínico, utilizando-se inibidor de aromatase / Gonadal steroids profile and expression of follicle-stimulating (FSH) and luteinizing (LH) hormones during the sex reversal of Epinephelus marginatus (Teleostei: Serranidae) hermaphroditic protogynous, using aromatase inhibitor

Garcia, Carlos Eduardo de Oliveira 03 August 2012 (has links)
A plasticidade do desenvolvimento gonadal em peixes, que contrasta com os padrões mais estáveis encontrados nos demais vertebrados, deu origem a várias questões intrigantes relativas tanto ao seu significado adaptativo quanto aos fatores genéticos e fisiológicos que modulam o processo. A inversão do sexo em peixes hermafroditas seqüenciais (protândricos ou protogínicos) ocorre em decorrência de diversos fatores, dentre eles, fisiológicos, genéticos e comportamentais podendo ser ainda decorrente do comportamento social. A garoupa verdadeira, Epinephelus marginatus é um peixe teleósteo, hermafrodita protogínico característico do litoral rochoso, maturando primeiramente como fêmeas, e posteriormente, na vida adulta, os ovários são substituídos por testículos, transformando-os em machos reprodutivamente ativos. No presente trabalho foram realizados três experimentos de inversão sexual em condições assistidas, em diferentes estações do ano, utilizando a mesma dose do inibidor de aromatase (IA) letrozole (100&mu;g/Kg) para promover a inversão sexual de E. marginatus visando contribuir e aprimorar o conhecimento dos mecanismos fisiológicos envolvidos nesse processo. O primeiro e o terceiro experimentos foram iniciados na primavera e início da primavera respectivamente e promoveram a inversão sexual com uma diminuição no índice gonadossomático (IGS) nos animais do grupo experimental que apresentaram uma desorganização gonadal peculiar, com lamelas características de ovário, no entanto em seu interior observou-se o compartimento intersticial desenvolvido com cistos de células germinativas masculinas em estágios avançados da espermatogênese, (espermatócitos, espermátides) células de Sertoli e grande quantidade de cistos rompidos com a liberação de espermatozoides no lúmen. Após trinta dias do início do experimento obteve-se um aumento significativo de 11 ceto-testosterona (11KT) e a concentração de estradiol (E2) permaneceu inalterada; com setenta e sete dias após o início do experimento constatou-se uma elevação na concentração de testosterona (T), uma queda nos níveis de 11KT, persistindo a manutenção na concentração de E2. Neste cenário, principalmente as concentrações de andrógenos podem ter ativado a alça de feedback negativo e juntamente com a ativação do sistema da kisspeptina podem ter promovido a ação do GnRH desviando a produção de FSH para LH. Nesse momento o número de cópias obtidas de &beta;FSH na hipófise foi significativamente menor que o número encontrado no grupo controle. Ao observarmos o aumento significativo da concentração plasmática de 17-alfaOHprogesterona podemos sugerir que a ação do GnRH tenha aumentado a secreção do LH, principal gonadotropina que estimula a produção de progestágenos. Os machos invertidos produziram um volume médio de sêmen de 118,20 ± 24,83 &mu;L com motilidade de 90% e densidade espermática de 8,94 ± 4,34 x 109 células mL-1. Não foram obtidas diferenças nas concentrações de proteínas totais plasmática, hepática e musculares. No experimento implantado no verão de 2010 o tratamento não promoveu a inversão sexual, o IGS não apresentou diferença significativa entre os animais tratados com inibidor de aromatase e os animais do grupo controle. Nas gônadas dos animais do grupo experimental foi observada uma ligeira desorganização da arquitetura gonadal com cistos em formação e um número grande de ovócitos em degeneração demonstrando que ao longo do processo de inversão sexual pode haver uma fase de intersexo. Após trinta dias do início do experimento obteve-se um aumento significativo de T e a concentração de E2 permaneceu inalterada. Não foram observadas diferenças significativas entre o número de cópias de &beta;FSH e &beta;LH ao longo do experimento. O resultado obtido para a concentração de proteínas totais do músculo dos animais do grupo experimental apresentou um aumento significativo em relação à concentração encontrada nos animais do grupo controle. Não ocorreu espermiação e a inversão se deu de forma incompleta promovendo indivíduos intersexo. De uma forma geral podemos concluir que o uso de inibidor de aromatase é um método eficaz para promover a inversão sexual em hermafroditas protogínicos como a garoupa verdadeira. O aumento dos andrógenos pode ser o gatilho da inversão sexual com papel fundamental na reestruturação gonadal e formação do tecido germinativo masculino neste processo / The plasticity of gonadal development in fish, which contrasts with the more stable patterns found in other vertebrates, has given rise to several thrilling questions concerning both, its adaptive significance regarding the genetic and physiological factors that modulate the process. The sex inversion in sequential hermaphrodites fish (protandrous or protogynuos) occurs due to several factors, including, physiological, genetic and behavioral, and may also be due to social behavior. The dusky grouper, Epinephelus marginatus is a teleost fish, protogynous hermaphrodite characteristic of rocky bottoms, maturing first as females and later in adult life, the ovaries are replaced by the testes, turning them into reproductively males. In this work three sex inversion experiments were performed in captivity in different seasons of the year, using the same dose of aromatase inhibitor (AI) letrozole (100&mu;g/Kg) to promote sexual inversion in E. marginatus, to contribute and improve the knowledge of the physiological mechanisms involved in this process. The first and third experiments started in the spring and early spring, respectively and promoted sexual inversion with a decrease in the gonadosomatic index (GSI) in the animals from the experimental group, that showed a peculiar disorganized gonadal, with lamellae, characteristic from ovaries, however with an interstitial compartment developed with cysts of male germ cells in advanced stages of spermatogenesis (spermatocytes, spermatids), Sertoli cells and a large amount of cysts ruptured with the release of sperm in the lumen. After thirty days from the beginning of the experiment, there was an increase in 11- ketotestosterone (11KT) levels and an unchanged concentration of estradiol (E2); after seventy-seven days, there was a significant increase in testosterone (T) levels, a decrease in the 11KT levels and the maintenance of E2 plasma concentration. In this point of view, mainly the concentration of androgens may have activated the negative feedback loop and with the activation of the kisspeptin system may have promoted the action of GnRH diverting the production of FSH to LH. At this moment the number of copies of pituitary &beta;FSH produced was ignificantly lower than the number of control group copies. The significant increase in plasma 17- alfaOHprogesterona concentration observed could suggest that the action of GnRH has increased the secretion of LH, the main gonadotropin that stimulates the production of progestogen. Inverted males produced an average volume of semen of 118.20 ± 24.83 &mu;l with 90% motility and sperm density of 8.94 ± 4.34 x 109 cells.ml-1. No differences were obtained at the concentrations of total protein in plasma, liver and muscle. In the experiment established in the summer of 2010, the treatment did not promote sexual inversion, the GSI was not significantly different between animals treated with aromatase inhibitor and the control group. In the gonads of the animals from the experimental group there was a slight disruption of gonadal architecture with cysts in formation and a large number of degenerating oocytes showing that during the process of sex inversion may be a phase of intersex. Thirty days after the beginning of the experiment there was a significant increase of T and E2 concentration remained unchanged. No significant differences were observed between the number of copies of &beta;FSH and &beta;LH throughout this experiment. The result obtained for the total protein concentration of the muscle in experimental group showed a significant increase compared with the control animals. There was no spermiation and the sex inversion occurred incompletely, with the presence of intersex individuals. In general we could conclude that the use of an aromatase inhibitor is an effective method to promote the sex inversion in hermaphroditic protogynous as the groupers. The increase of androgens could trigger the sex inversion exerting an important role in gonadal restructuring and the development of male germ tissue in the process

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