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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.
131

Desempenho reprodutivo de novilhas Angus submetidas à IATF utilizando cipionato de estradiol ou análogo do hormônio liberador das gonadotrofinas como indutores de ovulação / Reproductive performance angus heifers submitted to a tai using estradiol cypionate or gonadotropian releasing hormone analogue as ovulation inductors

Silva, Eduardo Pradebon da January 2016 (has links)
Este estudo teve como objetivo avaliar o efeito da presença de corpo lúteo (CL) no início do protocolo de inseminação artificial a tempo fixo (IATF), no diâmetro do folículo ovulatório (DFO), na expressão de estro e na taxa de prenhez usando cipionato de estradiol (CE) ou GnRH como indutor de ovulação em novilhas de corte. No dia 0, novilhas [n = 414; 317 ± 23 kg; 3,08 ± 0,21 escore de condição corporal (escala de 1 a 5) entre 22 e 24 meses de idade] receberam um dispositivo intravaginal contendo 1g de progesterona (P4) e foram administrados 2 mg de benzoato de estradiol, IM. No dia 8, o dispositivo foi removido e as novilhas receberam 500 μg de cloprostenol sódico IM e foram divididas em dois grupos: CE [n = 213; 0,5 mg de CE, IM, no dia 8] e GnRH [n = 201; 25 μg de Licerelina, IM, no dia da IATF] e a IATF foi realizada 50 h após a remoção do dispositivo. As novilhas tiveram a região sacral pintada para verificar a expressão do estro entre a remoção do dispositivo de P4 e a IATF. No dia 0, foram realizados exames ultrassonográficos para verificar a presença de CL (com CL = 213, sem CL = 202), no dia 10 para medir o DFO e no dia 11 para confirmar a ovulação. As novilhas foram classificadas em 3 grupos de acordo com o DFO: pequeno (≤ 9,5mm), médio (9,6-11,5mm) e grande (≥ 11,6mm) para avaliar seu efeito na expressão de estro e prenhez. A expressão de estro foi confirmada quando a tinta estava removida no dia 10. A expressão de estro foi maior (P <0,05) no grupo CE em comparação com o grupo GnRH. O DFO diferiu (P <0,05) de acordo com a presença de CL ( P < 0,05), mas foi semelhante entre os tratamentos. A taxa de ovulação não diferiu nos grupos CE e GnRH. As taxas de prenhez foram semelhantes (P> 0,05) entre os grupos CE e GnRH, no entanto, a taxa de prenhez foi maior nas novilhas que expressaram estro (P <0,05), do que naquelas que não expressaram. A presença de CL no início do protocolo de IATF esteve associada a maior taxa de prenhez (P <0,05) no grupo GnRH em relação ao grupo CE, mas não diferiu entre novilhas sem CL. A manifestação de estro para novilhas tratadas com GnRH aumenta de acordo com DFO. O grupo CE apresenta alta manifestação de estro independente do DFO. A taxa de prenhez é maior à medida que o DFO aumenta. Em conclusão, as novilhas com CL no início do protocolo de IATF possuem maior folículo ovulatório, e quando tratadas com GnRH como indutor de ovulação atingem maiores taxas de prenhez. O tamanho do folículo ovulatório foi associado com o comportamento de estro e as taxas de prenhez nos tratamentos de CE e GnRH. / The aim of this study was to evaluate the effect of presence of corpus luteum (CL) at the onset of timed AI (TAI) protocol in ovulatory follicle diameter (OFD), estrus expression and pregnancy rate using estradiol cypionate (EC) or GnRH as ovulation inductor in beef heifers. On day 0, heifers [n=414; 317±23 kg; 3.08±0.21 body condition score (1 to 5 scale) and 22-24 months of age] received a 1g progesterone (P4) intravaginal device and 2 mg of estradiol benzoate, IM,. On day 8, device was removed, heifers received 500 μg of sodium cloprostenol, IM, and were divided in two groups: EC [n=213; 0.5mg EC, IM, on day 8] and GnRH [n=201; 25 μg of Licerelin, IM, at TAI] TAI was performed 50 h after device removal. The heifers had the base of the tail painted to verify estrus expression between P4 device removal and IATF. On day 0, ultrasound examinations were performed to verify the presence of CL (with CL = 213, without CL = 202).On day 10 to measure OFD and on day 11 to confirm ovulation. Heifers were classified into three groups according to OFD: small (≤ 9.5 mm), medium (9.6-11.5 mm) and large (≥ 11.6 mm) to evaluate their effect on estrus expression and pregnancy rate. Estrus expression was confirmed when ink marking was removed on day 10. Estrus expression was higher (P <0.05) in the EC group compared to GnRH group. The OFD differed (P <0.05) according to the presence of CL (P <0.05), but was similar between the treatments. The ovulation rate did not differ in CE and GnRH groups. Pregnancy rates were similar (P> 0.05) between the EC and GnRH groups, however, the pregnancy rate was higher in heifers who expressed estrus (P <0.05) than in those who did not express it. The presence of CL at the beginning of the IATF protocol was associated with a higher pregnancy rate (P <0.05) in the GnRH group in relation to the EC group, but did not differ between heifers without CL. The estrus manifestation for heifers treated with GnRH increases as the DFO increases, while the EC heifers has a high estrus manifestation independent of the DFO. The pregnancy rate also increases as DFO increases. In conclusion, heifers with CL at the beginning of the IATF protocol have increased ovulatory follicle size, and when treated with GnRH, as an ovulation inducer, attained higher pregnancy rates. The size of the ovulatory follicle was associated with higher estrus behavior and higher pregnancy rates in the EC and GnRH treatments.
132

Studies On Growth And Development Of The Ovarian Dominant Follicle In Monovulatory Species : Analysis Of Transcriptional Changes And Factors Influencing Periovulatory Events

Rao, Jyotsna U 03 1900 (has links)
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.
133

Evaluation of the Expression of LIN28A and LIN28B within the Hypothalamic-pituitary-gonadal Axis

Grieco, Anthony 07 December 2011 (has links)
The genes that regulate pubertal timing in the general population are not well understood. Recently, genome-wide association studies have demonstrated that genetic variants near LIN28B associate with variation in pubertal timing in humans. To investigate where within the hypothalamic-pituitary-ovarian (HPO) axis Lin28b, and its homologue Lin28a, regulate pubertal timing, expression of these genes was assessed across the pubertal transition. The finding that Lin28a/b expression decreases only in the ovary suggests that the Lin28 pathway may exert its regulatory effects with respect to puberty in the ovary. Another aim of this thesis was to examine the effect of estrogen on Lin28b expression in immortalized GnRH neuronal cells, but the data remains equivocal and detailed future studies are needed to make definitive conclusions. The ovarian expression data lay the foundation for further studies using conditional knockout mice to verify the importance of the tissue and age specific developmental pattern that was identified.
134

Evaluation of the Expression of LIN28A and LIN28B within the Hypothalamic-pituitary-gonadal Axis

Grieco, Anthony 07 December 2011 (has links)
The genes that regulate pubertal timing in the general population are not well understood. Recently, genome-wide association studies have demonstrated that genetic variants near LIN28B associate with variation in pubertal timing in humans. To investigate where within the hypothalamic-pituitary-ovarian (HPO) axis Lin28b, and its homologue Lin28a, regulate pubertal timing, expression of these genes was assessed across the pubertal transition. The finding that Lin28a/b expression decreases only in the ovary suggests that the Lin28 pathway may exert its regulatory effects with respect to puberty in the ovary. Another aim of this thesis was to examine the effect of estrogen on Lin28b expression in immortalized GnRH neuronal cells, but the data remains equivocal and detailed future studies are needed to make definitive conclusions. The ovarian expression data lay the foundation for further studies using conditional knockout mice to verify the importance of the tissue and age specific developmental pattern that was identified.
135

Stimulation de cellules épithéliales bronchiques humaines par la GnRH : effet sur le transport ionique médié par le CFTR

Benz, Nathalie 13 December 2013 (has links) (PDF)
Introduction : La mucoviscidose est une maladie génétique autosomale récessive causée par des mutations dans le gène CFTR (cystic fibrosis transmembrane conductance regulator). Ce dernier code un canal chlorure AMPc-dépendant localisé dans la membrane apicale des cellules épithéliales, dont l'activité est régulée par de nombreuses interactions protéine-protéine. Dans le cadre de la recherche de nouveaux partenaires du CFTR, une interaction directe entre le canal (sauvage et muté F508del) etl'annexine A5 (AnxA5) a été mise en évidence dans notre laboratoire. Des stratégies de sur et de sousexpression nous ont également permis d'établir un lien fonctionnel entre les deux protéines. En effet, nos travaux montrent que les sécrétions ioniques dépendantes du CFTR sont corrélées au niveau d'expression intracellulaire de l'AnxA5. Par ailleurs, une élévation des courants médiés par le CFTR ainsi qu'une augmentation de la quantité de canaux dans la membrane plasmique sont observées suite à la surexpression de l'AnxA5 dans des cellules exprimant le CFTR muté F508del.But de l'étude : Au vu de ces observations, l'AnxA5 apparaît comme une cible potentielle pour la correction de certains défauts engendrés par la mutation F508del. Une piste thérapeutique pourrait être l'identification de composés capables d'augmenter son expression dans des cellules épithéliales exprimant le mutant F508del de la protéine CFTR. Considérant les informations fournies par la littérature, notre choix s'est porté sur la GnRH (gonadotropin-releasing hormone), molécule utilisée en thérapeutique humaine depuis plus de 25 ans. Ainsi, nous avons évalué l'effet de la GnRH sur la modulation de l'expression de l'AnxA5 et sur le transport ionique dépendant du CFTR dans nos différents modèles d'étude Résultats : Outre la présence du récepteur de la GnRH dans nos modèles cellulaires, nous montrons également que l'expression de l'AnxA5 y est augmentée dès 60 minutes de traitement avec l'hormone (1 nM). De plus, comparativement à des cellules non stimulées, des cellules prétraitées avec la GnRH présentent une hausse significative des sorties actives d'iodure, corrélant avec une augmentation de la quantité de CFTR à la surface cellulaire. Ces observations ont été faites dans les modèles exprimant le CFTR muté F508del ainsi que dans ceux exprimant le CFTR sauvage. Conclusion : Dans nos modèles et selon nos conditions de stimulation, un traitement avec la GnRH augmente l'expression intracellulaire de l'AnxA5 et conduit à une élévation des sécrétions ioniques médiées par le canal CFTR. Néanmoins, au vu de la multitude de voies de signalisation susceptibles d'être activées et de gènes pouvant être régulés suite à la liaison de la GnRH sur son récepteur, l'effet observé sur l'AnxA5 ne représente probablement pas le seul évènement cellulaire à l'origine de l'impact positif enregistré sur l'activité du canal CFTR.
136

Is it Just the Hormones? : Sex Steroids, Chronic Stress and Violence in Premenstrual Dysphoric Disorder

Segebladh, Birgitta January 2011 (has links)
Premenstrual depressive symptoms and mood swings affect 3-8% of women in fertile age. The female hormones are believed to be the cause. Progesterone is well studied, but estrogen is not, and either are other causes such as intimate partner violence and chronic stress. The aim in this thesis was to investigate the influence of hormones as well as psychological aspects on the most common problems among women seeking care for premenstrual symptoms. In a cross-sectional study, four groups of women were included: ongoing users of oral contraceptives, with or without adverse mood symptoms and previous users, with or without experience of adverse mood. Depression and anxiety were significantly more common in both groups with reported adverse mood, in comparison with their control groups with no adverse mood. Self-reported PMS was significantly more common in those women who reported adverse mood, however, there was no difference in prospectively defined PMS or PMDD between the two groups of previous users. In a RCT with 25 women completing the study, GnRH treatment were tested in combination with two different HRT add-back doses of estradiol, in combination with progesterone and placebo. The higher dose of estrogen 1.5 mg in combination with progesterone induced significantly more pronounced symptoms than in combination with placebo. The lower dose, 0.5 mg gave less symptom recurrence in combination with progesterone. Exposure to violence was investigated among PMDD patients, healthy controls and gynecological patients. Among the participating women, gynecological patients, reported physical and/or emotional abuse significantly more often than did PMDD patients, as well as healthy controls. Chronic stress was investigated with diurnal cortisol, and low-dose dexamethasone test.  There was no difference in diurnal secretion of cortisol between PMDD patients and controls. No difference in the degree of dexamethasone suppression was found between PMDD patients and controls. According to the results from these studies, the main symptom provoking factor in women with PMDD appears to be the estradiol and progesterone fluctuations across the menstrual cycle, whereas chronic stress and intimate partner violence appears to be less relevant.
137

Controle do ciclo estral e taxa de prenhez em matrizes de corte bovinas: efeitos hormonais, genéticos e ambientais / Control of the estrous cycle and pregnancy rate in beef cattle cows and heifers: effects hormonal, genetic and environmental

Gottschall, Carlos Santos January 2011 (has links)
Investigou-se o desempenho reprodutivo de novilhas e vacas de corte submetidas a protocolos de sincronização de estros para a inseminação artificial e a associação entre marcadores moleculares e desempenho reprodutivo. Exp.1 avaliou-se a antecipação da aplicação da PGF2a em programa de IATF com implante de progesterona em 306 vacas Angus, com cria ao pé. A antecipação da aplicação da PGF2a afetou a taxa de concepção à IATF e prenhez final (P<0,05), respectivamente de 60,9% e 89,1% quando comparados a PGF2a na retirada do dispositivo, respectivamente de 49,3% e 76,7%. Exp.2 avaliaram-se os efeitos do GnRH e da manifestação de estro sobre o desempenho reprodutivo em 197 vacas Angus submetidas à IATF. A manifestação de estro antes da IATF influenciou a taxa de prenhez à IATF (TxPIATF) e prenhez final, respectivamente de 46,6%, 78,6% (C/estro) e 33,0%, 60,6% (S/estro) (P<0,05). O GnRH no momento da IATF resultou em menor taxa de prenhez à IATF, 32,3%, comparado a ausência de GnRH 48,0% (P<0,05), mas não afetou a prenhez final, respectivamente de 69,7% e 70,4%. Houve interação entre estro e GnRH. Vacas C/estro-C/GnRH tiveram 31,4% de prenhez à IATF contra vacas C/estro- S/GnRH com 61,5% (P<0,05). Nas vacas sem estro, o GnRH não apresentou efeito (P>0,05) na TxPIATF (32,6% e 33,3%). O escore de condição corporal (ECC) afetou a taxa de manifestação de estro e a TxPIATF, com superioridade (P<0,05) para vacas > de 3,0. Exp.3 compararam-se os efeitos de diferentes protocolos para a IATF com o acasalamento por touros (Controle) sobre o desempenho reprodutivo de 249 vacas Angus. Formou-se 5 grupos: Controle; Crestar 2º uso; OvSynch; Primer 1ºuso e Primer 2ºuso. A IATF dos animais foi realizada 27 dias e 38 dias após o inicio da estação do grupo controle. Sete dias após a IATF iniciou o repasse com touros. A estação de acasalamento (EA) foi de 91 dias para o grupo controle e 64 e 53 dias para os grupos IATF. A taxa de prenhez ao final da EA não se diferenciou entre os grupos 83,9%. As perdas reprodutivas entre o diagnóstico de gestação e o nascimento foram de 10,5%, sem diferenças entre grupos. O ECC de fêmeas que emprenharam no grupo controle foi diferente do ECC de fêmeas vazias, mas não se diferenciou nos animais da IATF. Exp.4 avaliaram-se protocolos de inseminação sobre o índice reprodutivo em 249 novilhas Britânicas e cruzas, acasaladas aos 14 e 27 meses. Novilhas de 14 e 27 meses foram submetidas aos tratamentos Crestar ou inseminação artificial (IA) por 7 dias, seguida por mais 5 dias após PGF2a (grupo PGF2a) Novilhas de 27 meses também foram submetidas ao OvSynch. Foram avaliados o peso vivo, ECC, escore de trato reprodutivo (ETR) ao início da estação reprodutiva. Os tratamentos OvSynch e Crestar tiveram 100% dos animais inseminados (IATF), enquanto os grupos IA com PGF2a aos 14 e 27 meses tiveram, respectivamente 21,9% e 43,5%. Não houve diferença nas taxas de concepção entre tratamentos e idades (P>0,05), com valores respectivos de 46,5%, 56,3%, 64,7% para Crestar, OvSynch, PGF2a e de 44,4% e 57,1%, para 14 e 27 meses. A taxa de prenhez à IA(TF) foi de 46,5%, 56,3%, 23,4% para Crestar, OvSynch, PGF2a, com superioridade (P<0,05) a favor do Crestar e OvSynch. A taxa de prenhez à IA(TF) foi de 18,6% e 41,3% (P<0,01) para idades 14 e 27 meses. A taxa de prenhez final, após o repasse com touros, foi superior a 90% em todos os grupos (P<0,05). O ETR influenciou a taxa de prenhez após a inseminação. Exp.5 e 6 buscou-se uma associação entre a resposta reprodutiva e marcadores moleculares ligados aos genes do receptor para IGF-1, LH , Leptina, receptores do FSH e LH. Foram utilizados dados de 249 novilhas (Exp4.) e 249 vacas (Exp.3). Nas novilhas a prenhez à inseminação e a prenhez final foram de 41,0% e 91,6%. Nas novilhas não foram encontradas associações entre marcadores e reprodução. No rebanho das vacas a taxa de natalidade no ano subseqüente foi de 75,5%, sem diferenças entre tratamentos, idade e escore ovariano. O ECC influenciou a taxa de natalidade, respectivamente de 55,6%, 75,8% e 82,4% (P<0,05) para os animais com ECC menor que 2,5; 2,5 a 2,9; maior ou igual a 3,0 ao do inicio EA. Vacas homozigóticas no marcador AFZ-1 apresentaram 84,4% de natalidade em comparação as heterozigóticas com 71,5% (P<0,05). A presença do alelo*161 nomarcador HEL5 resultou em 33,3% de natalidade, contra 76,5% em vacas sem esse alelo (P<0,05). Os experimentos evidenciaram que a antecipação da aplicação da PGF2a resultou em aumento da taxa de prenhez à IATF. O ECC mostrou-se como importante preditor do desempenho reprodutivo em vacas de corte. O uso do GnRH concomitante à IATF em vacas com manifestação de estro induzido com benzoato resultou em menor resposta reprodutiva à IATF. A IATF proporcionou aumento nas taxas de inseminação em novilhas, especialmente nas submetidas ao acasalamento 14 meses. O escore de trato reprodutivo ao início da estação de acasalamento influenciou a precocidade de concepção das novilhas. O atraso da realização da IATF após o início da EA não afetou a taxa de prenhez final de vacas de cria quando comparado ao acasalamento por touros. Marcadores moleculares apresentaram associação com o desempenho reprodutivo de bovinos. / Were investigated the reproductive performance of beef heifers and cows submitted to different estrus synchronization protocols for artificial insemination and the association between molecular markers and reproductive performance. Trial.1 The anticipation of the application of PGF2a in TAI program with implantation of progesterone in 306 nursing Angus cows was evaluated. Anticipating the application of PGF2a affected (P <0.05) conception rate to TAI and final pregnancy, respectively 60.9% and 89.1% when compared to PGF2a in the removal of the device, respectively 49.3% and 76.7%. Trial.2 The effects of GnRH and oestrus on reproductive performance in 197 Angus cows subjected to TAI It were evaluated. The expression of oestrus before TAI influenced the pregnancy rate to TAI (TxPTAI) and final pregnancy (P<0.05), respectively 46.6%, 78.6% (oestrus) and 33.0%, 60.6% (No/oestrus). GnRH at the time of TAI resulted in lower pregnancy rate to TAI (32.3%) compared to the absence of GnRH (48.0%) (P<0.05) but did not affect the final pregnancy, respectively 69, 7% and 70.4%. There was interaction between GnRH and oestrus. Cows with oestrus and GnRH had 31.4% pregnancy for TAI cows against with oestrus without GnRH with 61.5% (P <0.05). In cows without oestrus, GnRH had no effect (P> 0.05) TxPTAI (32.6% and 33.3%). The body condition score (BCS) affected the rate of oestrus and TxPTAI, with higher (P <0.05) for cows > than 3.0. Trial.3 The effects of different protocols for TAI with mating by bulls (control) on the reproductive performance of 249 Angus cows were compared. It was formed five groups: Control; Crestar 2nd use; OvSynch; Primer new and Primer 2nd use. The TAI was performed 27 days and 38 days after the start breeding season in the control group. Seven days after TAI was realized the clean-up bulls. The mating season (MS) was 91 days for the control group and 64 and 53 days for TAI groups. Pregnancy rate at the end of MS did not differ between groups (83.9%). Reproductive failure between diagnosis of pregnancy and birth were 10.5%, without differences between groups. The BCS to pregnant cows in the control group differed from open cows, but it was not different in cows submitted to TAI. Trial.4 Different protocols to insemination on reproduction in 249 British and crossbred heifers, bred at 14 and 27 months were evaluated. Heifers to 14 and 27 months were treated Crestar or artificial insemination (AI) for 7 days, followed by more than 5 days after PGF2a (PGF2a group) Heifers 27 months were also submitted to OvSynch. We evaluated body weight, BCS, reproductive tract score (RTS) to the beginning of the breeding season. Treatments OvSynch and Crestar had 100% of the animals inseminated (TAI), while groups with PGF2a IA at 14 and 27 months were respectively 21.9% and 43.5%. There was no difference in conception rates between treatment and age (P>0.05), with respective values of 46.5%, 56.3%, 64.7% for Crestar, OvSynch, PGF2a, and 44.4% and 57.1% for 14 and 27 months. Pregnancy rate to AI (TAI) was 46.5%, 56.3%, 23.4% for Crestar, OvSynch, PGF2a, with higher (P <0.05) in favor of Crestar and OvSynch. Pregnancy rate to AI (TAI) was 18.6% and 41.3% (P <0.01) for ages 14 and 27 months. The final pregnancy rate after clean-up bulls was superior to 90% in all groups (P<0.05). The RTS influenced the pregnancy rate after insemination. Trial.5 and 6 we looking for an association between the reproductive response and molecular markers linked to genes for IGF-1 receptor, LH , Leptin, FSH and LH receptors. We used data from 249 heifers (Trial4.) and 249 cows (Trial.3). Pregnancy in heifers at insemination and final pregnancy were 41.0% and 91.6%. No associations were found between markers and reproduction in heifers. In the cow`s herd the birth rate in subsequent years was 75.5%, with no differences between treatments, age and ovarian score. The BCS has influenced the birth rate, respectively 55.6%, 75.8% and 82.4% (P <0.05) for animals with BCS less than 2.5, 2.5 to 2.9; greater than or equal to 3.0 to the beginning of the MS. Cows in homozygous marker AFZ-1 showed 84.4% of the birth rate compared with 71.5% (P <0.05) in heterozygous cows. The presence of allele*161 to HEL5 marker resulted in 33.3% of birth rate vs. 76.5% in cows without this allele (P<0.05). The experiments showed that the anticipation of the implementation of PGF2a resulted in increased pregnancy rate to TAI. BCS has proven to be an important predictor of reproductive performance in beef cows. The use of GnRH in cows with the oestrus induced with benzoate showed worse reproductive response to TAI. The TAI has provided increased rates of insemination in heifers, especially in heifers submitted to matting by 14 months. The reproductive tract score at the beginning of the breeding season influenced the speed of conception in heifers. The delay of the realization of TAI after the onset of MS did not affect the final pregnancy rate of beef cows when compared to breeding only by bulls. Molecular markers were associated with the reproductive performance of cattle.
138

Desempenho reprodutivo de novilhas Angus submetidas à IATF utilizando cipionato de estradiol ou análogo do hormônio liberador das gonadotrofinas como indutores de ovulação / Reproductive performance angus heifers submitted to a tai using estradiol cypionate or gonadotropian releasing hormone analogue as ovulation inductors

Silva, Eduardo Pradebon da January 2016 (has links)
Este estudo teve como objetivo avaliar o efeito da presença de corpo lúteo (CL) no início do protocolo de inseminação artificial a tempo fixo (IATF), no diâmetro do folículo ovulatório (DFO), na expressão de estro e na taxa de prenhez usando cipionato de estradiol (CE) ou GnRH como indutor de ovulação em novilhas de corte. No dia 0, novilhas [n = 414; 317 ± 23 kg; 3,08 ± 0,21 escore de condição corporal (escala de 1 a 5) entre 22 e 24 meses de idade] receberam um dispositivo intravaginal contendo 1g de progesterona (P4) e foram administrados 2 mg de benzoato de estradiol, IM. No dia 8, o dispositivo foi removido e as novilhas receberam 500 μg de cloprostenol sódico IM e foram divididas em dois grupos: CE [n = 213; 0,5 mg de CE, IM, no dia 8] e GnRH [n = 201; 25 μg de Licerelina, IM, no dia da IATF] e a IATF foi realizada 50 h após a remoção do dispositivo. As novilhas tiveram a região sacral pintada para verificar a expressão do estro entre a remoção do dispositivo de P4 e a IATF. No dia 0, foram realizados exames ultrassonográficos para verificar a presença de CL (com CL = 213, sem CL = 202), no dia 10 para medir o DFO e no dia 11 para confirmar a ovulação. As novilhas foram classificadas em 3 grupos de acordo com o DFO: pequeno (≤ 9,5mm), médio (9,6-11,5mm) e grande (≥ 11,6mm) para avaliar seu efeito na expressão de estro e prenhez. A expressão de estro foi confirmada quando a tinta estava removida no dia 10. A expressão de estro foi maior (P <0,05) no grupo CE em comparação com o grupo GnRH. O DFO diferiu (P <0,05) de acordo com a presença de CL ( P < 0,05), mas foi semelhante entre os tratamentos. A taxa de ovulação não diferiu nos grupos CE e GnRH. As taxas de prenhez foram semelhantes (P> 0,05) entre os grupos CE e GnRH, no entanto, a taxa de prenhez foi maior nas novilhas que expressaram estro (P <0,05), do que naquelas que não expressaram. A presença de CL no início do protocolo de IATF esteve associada a maior taxa de prenhez (P <0,05) no grupo GnRH em relação ao grupo CE, mas não diferiu entre novilhas sem CL. A manifestação de estro para novilhas tratadas com GnRH aumenta de acordo com DFO. O grupo CE apresenta alta manifestação de estro independente do DFO. A taxa de prenhez é maior à medida que o DFO aumenta. Em conclusão, as novilhas com CL no início do protocolo de IATF possuem maior folículo ovulatório, e quando tratadas com GnRH como indutor de ovulação atingem maiores taxas de prenhez. O tamanho do folículo ovulatório foi associado com o comportamento de estro e as taxas de prenhez nos tratamentos de CE e GnRH. / The aim of this study was to evaluate the effect of presence of corpus luteum (CL) at the onset of timed AI (TAI) protocol in ovulatory follicle diameter (OFD), estrus expression and pregnancy rate using estradiol cypionate (EC) or GnRH as ovulation inductor in beef heifers. On day 0, heifers [n=414; 317±23 kg; 3.08±0.21 body condition score (1 to 5 scale) and 22-24 months of age] received a 1g progesterone (P4) intravaginal device and 2 mg of estradiol benzoate, IM,. On day 8, device was removed, heifers received 500 μg of sodium cloprostenol, IM, and were divided in two groups: EC [n=213; 0.5mg EC, IM, on day 8] and GnRH [n=201; 25 μg of Licerelin, IM, at TAI] TAI was performed 50 h after device removal. The heifers had the base of the tail painted to verify estrus expression between P4 device removal and IATF. On day 0, ultrasound examinations were performed to verify the presence of CL (with CL = 213, without CL = 202).On day 10 to measure OFD and on day 11 to confirm ovulation. Heifers were classified into three groups according to OFD: small (≤ 9.5 mm), medium (9.6-11.5 mm) and large (≥ 11.6 mm) to evaluate their effect on estrus expression and pregnancy rate. Estrus expression was confirmed when ink marking was removed on day 10. Estrus expression was higher (P <0.05) in the EC group compared to GnRH group. The OFD differed (P <0.05) according to the presence of CL (P <0.05), but was similar between the treatments. The ovulation rate did not differ in CE and GnRH groups. Pregnancy rates were similar (P> 0.05) between the EC and GnRH groups, however, the pregnancy rate was higher in heifers who expressed estrus (P <0.05) than in those who did not express it. The presence of CL at the beginning of the IATF protocol was associated with a higher pregnancy rate (P <0.05) in the GnRH group in relation to the EC group, but did not differ between heifers without CL. The estrus manifestation for heifers treated with GnRH increases as the DFO increases, while the EC heifers has a high estrus manifestation independent of the DFO. The pregnancy rate also increases as DFO increases. In conclusion, heifers with CL at the beginning of the IATF protocol have increased ovulatory follicle size, and when treated with GnRH, as an ovulation inducer, attained higher pregnancy rates. The size of the ovulatory follicle was associated with higher estrus behavior and higher pregnancy rates in the EC and GnRH treatments.
139

Inseminação artificial em tempo fixo em porcas desmamadas associada à utilização de análogo do GnRH e eCG / Fixed-time artificial insemination in weaned sows associated with use of an analogue of GnRH e eCG

Baroncello, Edegar January 2015 (has links)
A inseminação artificial em tempo fixo (IATF), juntamente com a inseminação artificial pós-cervical (IAPC), permite uma redução expressiva da mão de obra e uma melhor utilização dos machos geneticamente superiores. O objetivo deste estudo foi avaliar a eficiência do eCG associado agonista de GnRH (buserelina) ou apenas buserelina para indução e sincronização da ovulação em porcas desmamadas e submetidos a apenas uma IATF. Um total de 495 femeas suínas desmamadas foram utilizadas, cuja detecção de estro foi realizada uma vez ao dia (07:30). As fêmeas foram divididas em três tratamentos: Controle (n = 165) - a primeira IA foi realizada no início do estro (0 h) e repetida a cada 24 h, posteriormente, durante o estro; Tratamento 2: eCG + GnRH (n = 165) – femeas receberam uma injeção intramuscular de 600 UI de eCG após o desmame, e uma injeção intramuscular de buserelina (10 μg) 86-89 h após a administração de eCG; Tratamento 3: GnRH - fêmeas receberam uma injeção intramuscular de buserelina (10 μg) 86-89 h após o desmame. Nos três grupos era realizada a exposição ao macho no dia seguinte ao desmame uma vez ao dia, e aquelas fêmeas que demostrassem estro eram retiradas dos protocolos de IATF. Os grupos tratados receberam uma única IA, 118-120 h após o desmame (30-33 h após a buserelina). A IAPC contou com doses homospérmicas (1,5 x 109 células de espermáticas/50 ml) que foram utilizadas nas femeas em todos os três tratamentos. Não houve diferenças entre os tratamentos quanto ao número de femeas em estro até o terceiro dia (P>0,05). O intervalo entre o desmame e a ovulação foi significativamente maior (P< 0,05) no grupo controle (141,5 ± 1,58 h) comparativamente aos tratamentos eCG+GnRH (133,3 ± 1,60 h) e GnRH (135,9 ± 1,57 h). As femeas do tratamento eCG+GnRH ovularam em média antes (P<0,05) em relação ao grupo GnRH (44,5 ± 1,74 vs 48,2 ± 1,73 h). A taxa de parto foi superior (P<0,05) no grupo de controle, comparativamente aos tratamentos eCG + GnRH e GnRH, mas não houve diferença (P>0,05) em leitões nascidos totais entre os tratamentos. O uso do GnRH, com ou sem a administração prévia de eCG, antecipa a ovulação nas fêmeas suínas desmamadas. Nas fêmeas tratadas com eCG+GnRH ou GnRH, há em maior percentual de fêmeas inseminadas fora do momento ideal, em relação à ovulação, o que pode prejudicar o desempenho reprodutivo, sendo necessários ajustes no momento de aplicação dos hormônios ou no momento da inseminação para estudos subsequentes. / Fixed-time artificial insemination (FTAI) together with post-cervical artificial insemination (PCAI), allows an expressive reduction in labor requirements and a wider use of higher indexing boars. The aim of this study was to evaluate the efficiency of eCG agonist of GnRH (buserelin) or just buserelin for induction and synchronization of ovulation in weaned sows and submitted to FTAI .A total of 495 weaned sows whose estrus detection was performed once daily (07:30 A.M), starting a day after weaning. The sows were allocated into three treatment groups: Control (n=165) – the first AI was performed at estrus onset (0 h) and repeated every 24 h thereafter during estrus; Treatment 2: eCG + GnRH (n=165) – sows received an intramuscular injection of 600 UI eCG after weaning, and an intramuscular injection of buserelin (10 μg) 86-89 h after eCG administration; Treatment 3: GnRH - sows received an intramuscular injection of buserelina (10 μg) 86-89 h after weaning. . In the three groups it was performed boar exposure in the following day to weaning once a day, and those sows that demonstrated oestrus were removed from FTAI protocols. Treated groups received a single AI, 118-120 h after weaning (30-33 h after buserelin). PCAI with homospermic doses (1.5 x 109 total of sperm cells/50 ml) were respectively performed in sows in all treatment group. There were no differences (P> 0,05) in number of sows that showed oestrus until the third day between treatments. The interval between weaning and ovulation was significantly higher (P< 0,05) in the control group (141,5 ± 1,58 h) comparatively the treatments eCG+GnRH (133,3 ± 1,60 h) and GnRH (135,9 ± 1,57 h). Sows of treatment eCG+GnRH ovulated earlier (P< 0,05) comparing to the GnRH group (44,5 ± 1,74 vs 48,2 ± 1,73 h). Higher (P<0,05) farrowing rate in control group comparatively to treatments eCG+GnRH e GnRH was observed, but there were no differences (P> 0,05) in total piglets born between treatments. Use of GnRH, with or without previous administration of eCG anticipates ovulation in sows weaned, in the sows treated with eCG + GnRH or GnRH, there is a greater percentage of females inseminated outside the ideal time, with respect to ovulation, it can harm the reproductive performance, with necessary adjustments at the time of application hormones or at the time of insemination for subsequent studies.
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Aplica??o de biot?cnicas para monitoramento e controle do ciclo estral de esp?cies silvestres do bioma caatinga / Application of biotechniques for monitoring and controlling the estrous cycle of wild species of caatinga biome

Peixoto, Gislayne Christianne Xavier 04 March 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-12-29T18:22:21Z No. of bitstreams: 1 GislayneChristianneXavierPeixoto_TESE.pdf: 2528597 bytes, checksum: 54797aa7e0919a87c62bd4fafcfb4ff4 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-02T21:19:23Z (GMT) No. of bitstreams: 1 GislayneChristianneXavierPeixoto_TESE.pdf: 2528597 bytes, checksum: 54797aa7e0919a87c62bd4fafcfb4ff4 (MD5) / Made available in DSpace on 2017-01-02T21:19:23Z (GMT). No. of bitstreams: 1 GislayneChristianneXavierPeixoto_TESE.pdf: 2528597 bytes, checksum: 54797aa7e0919a87c62bd4fafcfb4ff4 (MD5) Previous issue date: 2016-03-04 / O objetivo da presente tese foi aplicar biot?cnicas no monitoramento e controle do ciclo estral de esp?cie silvestres do bioma caatinga, como ferramenta para aperfei?oamento do manejo em cativeiro, bem como conserva??o ou multiplica??o dessas esp?cies. A tese foi dividida em 3 experimentos. No primeiro, foi realizado o monitoramento do ciclo estral de tatus-peba (Euphractus sexcinctus) por diferentes m?todos de monitoramento, na qual foi observado ciclo estral com dura??o de 23,5 ? 3,12 dias, com uma fase folicular de 8,8 ? 1,4 dias e 15,62 ? 2,1 dias de fase l?tea. Na fase folicular foram observadas secre??o sanguinolenta vaginal, edema vulvar, presen?a de muco e facilidade de introdu??o do swab, com pico de estr?geno de 240,66 ? 12,69 pg/ml e predom?nio de c?lulas superficiais na citologia vaginal, com visualiza??o de fol?culos ovarianos por ultrassonografia. Na fase l?tea foi observada aus?ncia de secre??o sanguinolenta e dificuldade de introdu??o do swab, al?m do aumento nos n?veis de progesterona (10,83 ? 1,86 ng/ml) e visualiza??o de corpo l?teo por ultrassom. No segundo experimento, dois protocolos para indu??o e sincroniza??o de estro foram testados em cutias (Dasyprocta leporina). O primeiro, consistia na administra??o de duas doses de cloprostenol (5?g) com intervalo de nove dias; e o segundo, na administra??o de 30 ?g de an?logo de GnRH, seguida da administra??o de cloprostenol (5?g) ap?s sete dias e uma nova dose de an?logo de GnRH (30?g) ap?s dois dias. N?o houve diferen?a estat?stica entre os protocolos testados (P=0.1009). Entretanto, a prostaglandina isolada promoveu a indu??o de estro em 40% das f?meas, em 3 e 6 dias, e as associa??es de cloprostenol e GnRH, em 60% das f?meas, em 4 e 10 dias, ap?s ?ltima dose administrada, com pico de estr?geno de 19,95 ? 2,41pg/ml e 9,67 ? 1,8pg/ml, respectivamente. Em ambos os tratamentos, essas f?meas mostraram caracter?sticas externas de estro como abertura e hiperemia vulvar, muco vaginal e f?cil penetra??o de swab. O terceiro experimento teve por objetivo comparar a efici?ncia de dois protocolos para sincroniza??o de estro e adaptar a t?cnica de insemina??o artificial (IA) em f?meas de catetos (Pecari tajacu), sendo este realizado ap?s identifica??o e aplica??o do m?todo de sincroniza??o mais eficaz. O primeiro protocolo baseava-se na administra??o dupla de cloprostenol (120?g) com intervalo de nove dias, e o segundo, na associa??o de 400 UI de gonadotrofina cori?nica equina e 200 UI de gonadotrofina cori?nica humana, em dose ?nica. Para a IA, as f?meas foram sincronizadas com a associa??o eCG e hCG. Todas as f?meas apresentaram estro. Com o uso do cloprostenol, as f?meas mostraram estro nove dias ap?s a ?ltima aplica??o da droga, e na associa??o, ap?s seis dias. Posteriormente ? realiza??o da IA, n?o foram visualizados embri?es por ultrassonografia. No entanto, duas f?meas apresentaram aumento uterino, com presen?a de l?quido anecog?nico no l?men, e n?veis altos de progesterona com 30 e 60 dias ap?s a ?ltima IA (67.08 ? 16.85 ng/ml e 73.42 ? 22.59 ng/ml, respectivamente). Assim, como conclus?o geral, o monitoramento da atividade ovariana em tatus-peba, bem como a indu??o e sincroniza??o em cutias e catetos, permitem o uso dessas biot?cnicas em larga escala, facilitando a gest?o dessas esp?cies em cativeiro. / The objective of the present thesis was to apply biotechnologies in monitoring and control the estrous cycle of wild species of the caatinga biome, as a tool for improving the management in captivity, as well as conservation or multiplication of these species. The thesis was divided into three experiments. The first was realized the monitoring of the estrous cycle in armadillos (Euphractus sexcinctus) by different monitoring methods, which was observed estrous cycle with duration of 23.5 ? 3.12 days, a follicular phase 8.8 ? 1.4 days and luteal phase of 15.62 ? 2.1 days. In the follicular phase were observed vaginal bloody discharge, vulvar edema, presence of mucus and ease of introduction of swab, with peak estrogen 240.66 ? 12.69 pg / ml and predominance of superficial cells in the vaginal cytology, with follicles observed by ovarian ultrasound. In the luteal phase was observed absence of bloody discharge and difficulty of introducing the swab, besides the increase in progesterone levels (10.83 ? 1.86 ng / ml) and corpus luteum viewing by ultrasound. In the second experiment, two protocols for induction and estrus synchronization were tested in agoutis (Dasyprocta leporina). The first consisted in the administration of two doses of cloprostenol (5?g) with nine-day interval; and the second, in the administration of 30 mcg GnRH analogue, followed by cloprostenol administration (5?g) after seven days and a new dose of GnRH analogue (30?g) after two days. There was no statistical difference between the protocols tested (P=0.1490). However, the isolated prostaglandin promoted estrus induction in 40% of females, 3 to 6 days, and cloprostenol and GnRH associations, 60% females, 4 and 10 days after last dose, with peak estrogen 19.95 ? 2,41pg / ml and 9.67 ? 1,8pg / ml, respectively. In both treatments, these females showed estrous external characteristics as opening and hyperemia vulvar, vaginal mucus and easy penetration swab. The third experiment was to compare the efficiency of two protocols for estrous synchronization and to adapt the artificial insemination (AI) in collared peccary females (Pecari tajacu), which was carried out after identification and to appliction the most effective method of synchronization. The first protocol was based on the dual administration of cloprostenol (120?g) with nine-day interval, and the second, in the association of 400 IU equine chorionic gonadotrophin (eCG) and 200 IU of human chorionic gonadotropin (hCG), a single dose. For IA, females were synchronized with eCG and hCG association. All females exhibited estrus. With the use of cloprostenol, females exhibited estrus nine days after the last drug application, and with use of the association, after six days. After the realization of AI, were not observed embryos by ultrasound. However, two females showed increased uterine with presence of anechogenic fluid in the lumen, and high levels of progesterone 30 to 60 days after the last IA (67.08 ? 16.85 ng / mL and 73.42 ? 22.59 ng / ml, respectively). Thus, as the general conclusion, the monitoring of ovarian activity in armadillos as well as the induction and synchronization in agouti and peccaries, allow the use of these biotechnologies in large scale, facilitating the management of these species in captivity.

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