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Aspiration of equine oocytes from immature follicles after treatment with equine pituitary extract (EPE) alone or in combination with hCG

BLANCO, I. D. P; DEVITO, L. G; FERREIRA, H. N; ARAUJO, G. H. M; FERNANDES, Claudia Barbosa; ALVARENGA, M. A; LANDIM-ALVARENGA, Fernanda da Cruz
Fonte: Amsterdam Publicador: Amsterdam
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
27.34%
This study examined the effect of treating mares with equine pituitary extract (EPE) alone or in combination with hCG on the recovery rate of immature follicles by transvaginal follicular aspiration (ovum pick-up; OPU). Ten normally cycling crossbred mares aged 3–15 years and weighing 350–400 kg were subjected to each of three treatments in a random sequence with each exposure to a new treatment separated by a rest cycle during which a spontaneous ovulation occurred. The treatments were (1) superovulated with 25 mg EPE and treated with 2500 IU hCG, (2) superovulation with 25 mg EPE, and (3) control (no exogenous treatment). Treatments 7 days after spontaneous ovulation; and all the follicles >10 mm were aspirated 24 h after the largest follicle achieved a diameter of 27–30 mm for control group, and most follicles reached 22–27 mm for the EPE alone treatment. To the group EPE + hCG, when the follicles reached 22–27 mm, hCG was administered, 24 h before OPU. Superovulation increased the number of follicles available for aspiration. The total number of follicles available for aspiration was 61 in the EPE/hCG group, 63 in the EPE group and 42 in the control. The proportion of follicles aspirated varied from 63.5% to 73.8%. Oocyte recovery rate ranged from 15.0% to 16.7% and the proportion of mares that yielded at least one oocyte was 70% (7/10) in the EPE/hCG...

Diferentes protocolos de superovulação com inseminação artificial em tempo fixo em Bos taurus e Bos indicus; Different superovulation protocols with fixed time artificial insemination in Bos taurus and Bos indicus

Martins, Claudiney de Melo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/08/2007 PT
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37.34%
Esse estudo está apresentado em Capítulo 1 (Protocolo de Superovulação com IATF em Bos taurus) e Capítulo 2 [Protocolos de superovulação com IATF em Bos indicus, com 3 experimentos; 1- Momento da administração de LH em vacas Nelore (Bos indicus) superovuladas e inseminadas em tempo fixo; 2- Efeito da administração de progesterona injetável no início do protocolo de sincronização para superovulação com IATF em vacas Nelore; 3- Efeito do número de inseminações em vacas Nelore superovuladas e inseminadas em tempo fixo]. No Capítulo 1 objetivou-se avaliar o momento da retirada do dispositivo de P4 (DIB®) e da administração de LH em vacas Holandesas. Dezesseis vacas receberam DIB (D-1) e 2mg de BE (D0). Superovulou-se com 200mg de FSHp em 8 doses decrescentes a partir do D4. No D6, administrou-se PGF e estabeleceram-se quatro grupos: P24LH48 (retirada do DIB 24h e LH 48h pós PGF); P24LH60 (retirada 24h e LH 60h); P36LH48 (retirada 36h e LH 48h) e P36LH60 (retirada 36h e LH 60h; fatorial 2x2; cross-over). Realizou-se a IATF 12 e 24h pós LH. Os efeitos principais para P24vsP36 e LH48vsLH60 foram: taxa de ovulação (TO; 49,9 ± 5,7 vs 60,9± 4,8% e 53,1±5,3 vs 57,5±5,4%; P>0,05), estruturas totais (ETot; 4...

Efeito da insulina sobre a superovulação de ovelhas e desenvolvimento de um sistema nanoestruturado para permeação de mucosa; Insulin Effect on Sheep Superovulation and the Development of a nanostructure systemfor mucosal permeability

Brandão, Humberto de Mello
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 17/12/2009 PT
Relevância na Pesquisa
37.64%
A nutrição é o principal fator que interfere com o desempenho reprodutivo de mamíferos e vários metabólitos e hormônios, envolvidos no metabolismo energético, funcionam como sinalizadores para o eixo hipotálamo-hipófise-gonadal. O fato de a insulina ser o principal regulador da homeostase de glicose e exercer controle em diversas etapas do metabolismo de gorduras e proteínas, fez desse hormônio, ao longo do processo evolutivo, um modulador da reprodução. Neste estudo, no experimento 1, foi comparado o efeito da hiper e da hipoinsulinemia, no desempenho reprodutivo relacionado ao processo de superovulação em ovelhas. Para tanto foram utilizadas 27 ovelhas, distribuídas em 3 grupos: a) controle; b) grupo diabético (induzido pela aplicação I.V. de 50mg/kg de Alloxano); e c) grupo hiperinsulinêmico (suplementado com 1 UI/kg ao dia, S.C.). Todos os animais receberam um pessário vaginal, contendo 60 mg de medroxiprogesterona no D0 e foram superovulados, com 250UI de FSH em 6 aplicações, iniciadas no D10. No D12 aplicaram-se 250UI de eCG e 125 g de cloprostenol sódico. As ovelhas foram submetidas à monta natural e a colheita dos embriões foi realizada no sétimo dia após o início do estro. Em média, os teores de insulina medidos a partir da remoção dos pessários até a colheita dos embriões foram de 14...

Fatores associados à produção e à sobrevivência embrionária em programas de superovulação e transferência de embriões em fêmeas da raça Holandesa em clima tropical; Factors associated to embryo production and survival in superovulation programs and embryo transfer in Holstein females raised in tropical climate

Vieira, Lais Mendes
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/02/2013 PT
Relevância na Pesquisa
37.34%
A alta variabilidade na resposta aos tratamentos superovulatórios e na produção de embriões tem sido relacionada a causas multifatoriais. Além disso, são restritas as informações que relacionam fatores correlatos ao embrião à concepção. Dessa forma, o objetivo do presente estudo foi avaliar a influência de variáveis relacionadas às doadoras (categoria animal e época do ano de produção do embrião) na eficiência de programas de superovulação (SOV), assim como na eficiência reprodutiva de receptoras em programas de transferência de embrião. Foram avaliados dados de 1.562 protocolos de SOV (609 em vacas em lactação e 953 em novilhas da raça Holandesa) e 4.076 transferências de embrião (receptoras Holandesas em lactação). A taxa de SOV (número de doadoras com dois ou mais CL) foi semelhante entre novilhas e vacas em lactação (89,7 vs. 91,9%, respectivamente; P = 0,26). A época do ano, também, não influenciou a taxa de SOV (época quente = 89,3% vs. época não quente = 92,2%; P = 0,09). Doadoras lactantes apresentaram maior número de CL (10,6 ± 0,6 vs. 7,5 ± 0,4; P < 0,0001), de estruturas recuperadas (7,6 ± 0,6 vs. 4,6 ± 0,4; P < 0,0001) e taxa de recuperação (77,6 vs. 58,7%; P < 0,0001) que novilhas. Doadoras superovuladas na época quente apresentaram menor número de CL (8...

Comparison of three protocols for superovulation of brown brocket deer (Mazama gouazoubira)

Zanetti, Eveline dos Santos; Barbanti Duarte, Jose Mauricio
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 642-655
ENG
Relevância na Pesquisa
27.34%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); This study aims to evaluate the ovulation rate and the presence of functional corpora lutea after treatment by three different protocols designed to cause superovulation in brown brocket deer. Six female received an intravaginal device containing 0.33?g of progesterone (CIDR (R)) for 8 days, followed by 0.5?mg injection of estradiol benzoate at the time of insertion and 265?mu g of cloprostenol at the time of removal. Afterwards, the hinds were divided into three groups (n = 2): Treatment A received injection of 600?IU?eCG on Day 4 after CIDR (R) insertion; Treatment B received injection of 300?IU?eCG at the same time; and Treatment C received injection of 250?IU FSH dissolved in PVP, also on Day 4 post-insertion. The treatments were crossed over with 4448 day intervals after CIDR (R) removal, such that all the deer were submitted to all three treatments. The mean ovulation rate (Treatment A = 3.40 +/- 0.68, Treatment B = 1.40 +/- 0.24, Treatment C = 0.80 +/- 0.49), total ovarian stimulation (Treatment A = 4.80 +/- 1.02, Treatment B = 1.80 +/- 0.37...

Aspiration of equine oocytes from immature follicles after treatment with equine pituitary extract (EPE) alone or in combination with hCG

Blanco, I. D. P.; Devito, L. G.; Ferreira, H. N.; Araujo, G. H. M.; Fernandes, C. B.; Alvarenga, M. A.; Landim e Alvarenga, Fernanda da Cruz
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 203-209
ENG
Relevância na Pesquisa
27.34%
This study examined the effect of treating mares with equine pituitary extract (EPE) alone or in combination with hCG on the recovery rate of immature follicles by transvaginal follicular aspiration (ovum pick-up; OPU). Ten normally cycling crossbred mares aged 3-15 years and weighing 350-400 kg were subjected to each of three treatments in a random sequence with each exposure to a new treatment separated by a rest cycle during which a spontaneous ovulation occurred. The treatments were (1) superovulated with 25 mg EPE and treated with 2500 IU hCG, (2) superovulation with 25 mg EPE, and (3) control (no exogenous treatment). Treatments 7 days after spontaneous ovulation; and all the follicles > 10 mm were aspirated 24 h after the largest follicle achieved a diameter of 27-30 mm for control group, and most follicles reached 22-27 mm for the EPE alone treatment. To the group EPE+hCG, when the follicles reached 22-27 mm, hCG was administered, 24 h before OPU. Superovulation increased the number of follicles available for aspiration. The total number of follicles available for aspiration was 61 in the EPE/hCG group. 63 in the EPE group and 42 in the control. The proportion of follicles aspirated varied from 63.5% to 73.8%. Oocyte recovery rate ranged from 15.0% to 16.7% and the proportion of mares that yielded at least one oocyte was 70% (7/10) in the EPE/hCG...

Superovulation in mares: Limitations and perspectives

Alvarenga, Marco A.; Carmo, Marcio T.; Landim e Alvarenga, Fernanda da Cruz
Fonte: Hippiatrika Verlag Mbh Publicador: Hippiatrika Verlag Mbh
Tipo: Artigo de Revista Científica Formato: 88-91
ENG
Relevância na Pesquisa
37.52%
Superovulation is an important tool for routine use in equine embryo transfer (ET) in order to reduce the costs and to enhance the efficiency of ET programs. Satisfactory superovulatory answers (2-7 ovulations) have been reported in mares treated with Equine Pituitary Extract (EPE) and more recently using a commercial Equine FSH. However, embryo recovery rates have been inconsistent and below expectations (20-50% embryos/ovulation). Recent studies have shown that superovulatory treatment leads to disturbances in oocyte maturation and transport, especially in mares with a high ovarian response. Higher and more consistent embryo recovery rates per ovulation have been observed in mares treated with lower doses of EPE. This paper presents a review of recent studies related to superovulation in mares.

Ovarian response to superovulation in Nelore cows (Bostaurusindicus L.)

Becker, W. A P; Pinheiro, L. E L
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 785-793
ENG
Relevância na Pesquisa
37.52%
Superovulation was induced in 15 Nelore cows with porcine follicle stimulating hormone (FSH-P) or pregnant mare serum gonadotropin (PMSG), and embryos were collected to compare the response of this breed of cattle to these hormones. FSH-P was given in 30-and 40-mg doses for 5 d as a single daily injection or fractionated into two daily injections. PMSG was given in doses of 1000 and 2000 IU. The animals were killed immediately after embryo collection and the ovaries and genitalia were examined clinically. PMSG proved to be more effective in inducing superovulation than FSH-P, probably because PMSG caused no stress since it was administered as a single dose. No differences were observed between the 30-and 40-mg dose of FSH-P or between the application as a single or fractionated dose. Differences did occur, however, between the number of ovulations and embryos obtained at each collection. On the basis of postmortem analysis, we concluded that lack of egg uptake by the infundibulum had occurred in cases of increased ovulation, with excessive increase in volume of the ovary. We also recommend using smaller doses of FSH-P and suggest that avoiding stress in handling is essential for a good response to hormonal stimulation by Zebu cattle. © 1986.

Repeatability and heritability of response to superovulation in Holstein cows

Tonhati, Humberto; Lôbo, R. B.; Oliveira, H. N.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1151-1156
ENG
Relevância na Pesquisa
37.89%
The objective of this study was to estimate the relative effects of genetic and phenotypic factors on the efficacy and efficiency of superovulation for Holstein-Friesian cows reared in Brazil. A database, established by the Associacao Brasileira de Criadores de Bovinos da Raca Holandesa, consisting of a total of 5387 superovulations of 2941 cows distributed over 473 herds and sired by 690 bulls was used for the analysis. The records were analyzed by MTDFREML (Multiple Trait Derivative-Free Restricted Maximum Likelihood), using a repeatability animal model. The fixed effects included in the model were contemporaneous group (veterinarian, herd, year and season of the superovulation); number of semen doses; cow age; and superovulation order. The estimated repeatability of the number of the transferable embryos was low (0.13), and the estimated heritability was 0.03. These results indicate that environmental factors play a critical role in the response of a cow to a superovulation treatment. There is little evidence that future responses to superovulation by individual females can be predicted by previous treatment(s) or that superovulation response is an heritable trait.

Superovulation in Cycling Mares Using Equine Follicle Stimulating Hormone (eFSH)

Niswender, K. D.; Alvarenga, M. A.; McCue, P. M.; Hardy, Q. P.; Squires, E. L.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 497-500
ENG
Relevância na Pesquisa
27.52%
Superovulation would potentially increase the efficiency and decrease the cost of embryo transfer by increasing embryo collection rates. Other potential clinical applications include improving pregnancy rates from frozen semen, treatment of subfertility in stallions and mares, and induction of ovulation in transitional mares. The objective of this study was to evaluate the efficacy of purified equine follicle stimulating hormone (eFSH; Bioniche Animal Health USA, Inc., Athens, GA) in inducing superovulation in cycling mares. In the first experiment, 49 normal, cycling mares were used in a study at Colorado State University. Mares were assigned to 1 of 3 groups: group 1, controls (n = 29) and groups 2 and 3, eFSH-treated (n = 10/group). Treated mares were administered 25 mg of eFSH twice daily beginning 5 or 6 days after ovulation (group 2). Mares received 250 (of cloprostenol on the second day of eFSH treatment. Administration of eFSH continued until the majority of follicles reached a diameter of 35 mm, at which time a deslorelin implant was administered. Group 3 mares (n = 10) received 12 mg of eFSH twice daily starting on day 5 or 6. The treatment regimen was identical to that of group 2. Mares in all 3 groups were bred with semen from 1 of 4 stallions. Pregnancy status was determined at 14 to 16 days after ovulation. In experiment 2...

Protocolos de superovulação em vacas da raça Gir quanto ao número de estruturas totais, embriões viáveis e degenerados

Prado, Fabrício Rasi de Almeida
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 51 f.
POR
Relevância na Pesquisa
27.52%
Pós-graduação em Medicina Veterinária - FMVZ; Foram avaliadas 57 vacas da raça Gir PO, não lactantes, com escore corporal de 3,5 a 4,0 numa escala de zero a cinco pontos. As doadoras foram distribuídas em três grupos de forma aleatória, onde A (n=19), B (n=19) e C (n=19). As doadoras do grupo A foram superovuladas com 300 UI de FSH, o grupo B com 400 UI de FSH e o grupo C com 500 UI de FSH. Foi utilizado CIDR e administrado, via intramuscular, 2,5 mg de benzoato de estradiol. Cinco dias mais tarde, inicia-se o tratamento superestimulatório com diferentes concentrações de FSH. Com a última aplicação de FSH, administrou-se PGF2a, via intramuscular e doze horas após a aplicação da PGF2a foi retirado o CIDR. As vacas superovulados receberam uma dose de 50 æg de GnRH, via intramuscular, doze horas após a retirada do CIDR. As doadoras foram inseminadas doze horas após a aplicação de GnRH com duas doses de sêmen, em intervalos de doze horas entre as mesmas. As doses de sêmen utilizadas foram do mesmo touro e da mesma partida. Para análise estatística do potencial de desenvolvimento dos protocolos de superovulação, as proporções de embriões viáveis entre os tratamentos foram comparadas pelo teste de Qui-quadrado ( )...

Effects of environmental factors on multiple ovulation of zebu donors

Peixoto,M.G.C.D.; Bergmann,J.A.G.; Fonseca,C.G.; Penna,V.M.; Pereira,C.S.
Fonte: Universidade Federal de Minas Gerais, Escola de Veterinária Publicador: Universidade Federal de Minas Gerais, Escola de Veterinária
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2006 EN
Relevância na Pesquisa
27.89%
Data on 1,294 superovulations of Brahman, Gyr, Guzerat and Nellore females were used to evaluate the effects of: breed; herd; year of birth; inbreeding coefficient and age at superovulation of the donor; month, season and year of superovulation; hormone source and dose; and the number of previous treatments on the superovulation results. Four data sets were considered to study the influence of donors’ elimination effect after each consecutive superovulation. Each one contained only records of the first, or of the two firsts, or three firsts or all superovulations. The average number of palpated corpora lutea per superovulation varied from 8.6 to 12.6. The total number of recovered structures and viable embryos ranged from 4.1 to 7.3 and from 7.3 to 13.8, respectively. Least squares means of the number of viable embryos at first superovulation were 7.8 ± 6.6 (Brahman), 3.7 ± 4.5 (Gyr), 6.1 ± 5.9 (Guzerat) and 5.2 ± 5.9 (Nellore). The numbers of viable embryos of the second and the third superovulations were not different from those of the first superovulation. The mean intervals between first and second superovulations were 91.8 days for Brahman, 101.8 days for Gyr, 93.1 days for Guzerat and 111.3 days for Nellore donors. Intervals between the second and the third superovulations were 134.3...

The association of two single nucleotide polymorphisms (SNPs) in growth hormone (GH) gene with litter size and superovulation response in goat-breeds

Zhang,Chunyan; Liu,Yun; Huang,Kunkun; Zeng,Wenbing; Xu,Deqing; Wen,Qunying; Yang,Liguo
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
Relevância na Pesquisa
37.73%
Two active mutations (A 781 G and A 1575 G) in growth hormone (GH) gene, and their associations with litter size (LS), were investigated in both a high prolificacy (Matou, n = 182) and a low prolificacy breed (Boer, n = 352) by using the PCR-RFLP method. Superovulation experiments were designed in 57 dams, in order to evaluate the effect of different genotypes of the GH gene on superovulation response. Two genotypes (AA and AB, CC and CD) in each mutation were detected in these two goat breeds. Neither BB nor DD homozygous genotypes were observed. The genotypic frequencies of AB and CC were significantly higher than those of AA and CD. In the third parity, Matou dams with AB or CC genotypes had significantly larger litter sizes than those with AA and CD (p < 0.05). On combining the two loci, both Matou and Boer dams with ABCD genotype had the largest litter sizes when compared to the other genotypes (p < 0.05). When undergoing like superovulation treatments, a significantly higher number of corpora lutea and ova, with a lower incidence of ovarian cysts, were harvested in the AB and CC genotypes than in AA and CD. These results show that the two loci of GH gene are highly associated with abundant prolificacy and superovulation response in goat breeds.

The association of two single nucleotide polymorphisms (SNPs) in growth hormone (GH) gene with litter size and superovulation response in goat-breeds

Zhang, Chunyan; Liu, Yun; Huang, Kunkun; Zeng, Wenbing; Xu, Deqing; Wen, Qunying; Yang, Liguo
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.64%
Two active mutations (A 781 G and A 1575 G) in growth hormone (GH) gene, and their associations with litter size (LS), were investigated in both a high prolificacy (Matou, n = 182) and a low prolificacy breed (Boer, n = 352) by using the PCR-RFLP method. Superovulation experiments were designed in 57 dams, in order to evaluate the effect of different genotypes of the GH gene on superovulation response. Two genotypes (AA and AB, CC and CD) in each mutation were detected in these two goat breeds. Neither BB nor DD homozygous genotypes were observed. The genotypic frequencies of AB and CC were significantly higher than those of AA and CD. In the third parity, Matou dams with AB or CC genotypes had significantly larger litter sizes than those with AA and CD (p < 0.05). On combining the two loci, both Matou and Boer dams with ABCD genotype had the largest litter sizes when compared to the other genotypes (p < 0.05). When undergoing like superovulation treatments, a significantly higher number of corpora lutea and ova, with a lower incidence of ovarian cysts, were harvested in the AB and CC genotypes than in AA and CD. These results show that the two loci of GH gene are highly associated with abundant prolificacy and superovulation response in goat breeds.

Superovulation Using the Combined Administration of Inhibin Antiserum and Equine Chorionic Gonadotropin Increases the Number of Ovulated Oocytes in C57BL/6 Female Mice

Takeo, Toru; Nakagata, Naomi
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 29/05/2015 EN
Relevância na Pesquisa
27.85%
Superovulation is a reproductive technique generally used to produce genetically engineered mice. Superovulation in mice involves the administration of equine chorionic gonadotropin (eCG) to promote follicle growth and then that of human chorionic gonadotropin (hCG) to induce ovulation. Previously, some published studies reported that inhibin antiserum (IAS) increased the number of ovulated oocytes in ddY and wild-derived strains of mice. However, the effect of IAS on the C57BL/6 strain, which is the most widely used inbred strain for the production of genetically engineered mice, has not been investigated. In addition, the combined effect of IAS and eCG (IASe) on the number of ovulated oocytes in superovulation treatment has not been examined. In this study, we examined the effect of IAS and eCG on the number of ovulated oocytes in immature female mice of the C57BL/6 strain in superovulation treatment. Furthermore, we evaluated the quality of obtained oocytes produced by superovulation using IASe by in vitro fertilization (IVF) with sperm from C57BL/6 or genetically engineered mice. The developmental ability of fresh or cryopreserved embryos was examined by embryo transfer. The administration of IAS or eCG had a similar effect on the number of ovulated oocytes in C57BL/6 female mice. The number of ovulated oocytes increased to about 3-fold by the administration of IASe than by the administration of IAS or eCG alone. Oocytes derived from superovulation using IASe normally developed into 2-cell embryos by IVF using sperm from C57BL/6 mice. Fresh or cryopreserved 2-cell embryos produced by IVF between oocytes of C57BL/6 mice and sperm from genetically engineered mice normally developed into live pups following embryo transfer. In summary...

Superovulation chez la vache laitière : impact de la progestéronémie

Pelletier, Jean-Philippe
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
Relevância na Pesquisa
37.93%
Les récentes recherches suggèrent que la superovulation de vaches laitières sous une concentration élevée de progestérone permet de meilleurs résultats que la superovulation sous une basse progestéronémie pendant la première vague folliculaire. Nous émettions donc l’hypothèse qu’une basse progestéronémie pendant la phase lutéale, une problématique connue chez la vache laitière haute productrice, compromet le rendement en embryons suite à la superovulation de la deuxième vague folliculaire. Afin de tester cette hypothèse, 18 vaches laitières ont été superovulées à deux reprises avec deux protocoles distincts, dont un atteignant un niveau lutéal de progestérone (>2.5 ng/mL, le corps jaune comme source de progestérone) et l’autre un niveau sublutéal (<2.5 ng/mL, l’implant intravaginal comme unique source de progestérone). Le nombre d’embryons transférables était similaire entre les protocoles. Curieusement, nous avons obtenu un développement accéléré des follicules dans le protocole sublutéal (p = 0,002), un développement embryonnaire plus avancé (p = 0,01) et une qualité améliorée des embryons (p = 0,02) par rapport au protocole lutéal. Ces résultats suggèrent que des facteurs autres qu’une basse progestéronémie peuvent affecter le rendement en embryons. Une pulsatilité augmentée de la LH grâce à une basse progestéronémie pendant la deuxième vague folliculaire pourrait être responsable du développement folliculaire accru ainsi que du développement et de la qualité augmentés des embryons. Ces résultats indiquent que des niveaux sublutéaux de progestérone pendant la phase lutéale ne compromettent pas le résultat d’un traitement de superovulation mais...

Estratégias para aumentar a recuperação de estruturas embrionárias de búfalas superovuladas; Strategies to increase embryo recovery of superovulated buffaloes

Soares, Júlia Gleyci
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/04/2015 PT
Relevância na Pesquisa
27.64%
Apesar de inúmeros estudos desenvolvidos no Brasil e no mundo, a utilização das biotecnologias de superovulação (SOV) e transferência de embriões (TE) em bubalinos ainda apresenta resultados inconsistentes, associados à principalmente à baixa taxa de recuperação de embriões. Dessa forma, o objetivo do presente estudo foi avaliar o efeito da utilização de dispositivo de P4 (para promover diminuição da contratilidade do trato genital, Capitulo 1) ou da administração de PGF2α (para promover aumento da atividade da fímbria e da frequência do batimento ciliar, Capítulo 2) durante o período periovulatório na captação dos oócitos pelas fímbrias e no aumento da produção de embriões em búfalas superovuladas. No Experimento 1 (Capítulo 1), doadoras bubalinas foram homogeneamente divididas em dois grupos: controle (G-C; n=8) e tratamento com progesterona (P4) durante o período periovulatório (G-P4; n=8). A emergência da onda de crescimento folicular foi sincronizada com um dispositivo intravaginal de P4 e a administração de 2 mg i.m. de benzoato de em dia aleatório do ciclo estral (Dia 0; D0). A partir do D4, todas as búfalas receberam 200 mg i.m. de FSH duas vezes ao dia, em 8 doses decrescentes. Foram administrados 530µg i.m. de PGF2α no D6 e no D7. A P4 foi removida do G-C no D7 e do G-P4 no D10. No D8...

Superovulação de novilhas da raça Nelore com diferentes doses de FSH/LH e congelação de embriões pelo método one-step com etilenoglicol; Superovulation of Nelore heifers with different FSH/LH doses and embryo freezing by one-step method with ethylene-glycol

Visintin, José Antonio; Arruda, Rubens Paes de; Madureira, Ed Hoffman; Mizuta, Katia; Celeghini, Eneiva Carla Carvalho; Assumpção, Mayra Elena Ortiz D’Avila; Gusmões, Pedro Paulo Gimenes; Candini, Pedro Henrique
Fonte: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia Publicador: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/01/1999 POR
Relevância na Pesquisa
37.34%
Este trabalho teve como objetivo identificar a dose mais eficiente de FSH/LH (300, 400 e 500 UI) no tratamento superovulatório de novilhas da raça Nelore, assim como avaliar o método one-step no processo de congelação de embriões. A variação da resposta superovulatória tem sido muito grande, o que explica o interesse de diversos pesquisadores em encontrar novos hormônios, doses e momentos para realizar a estimulação ovariana. Foram empregadas doses de 300 (n = 20), 400 (n = 21) ou 500 UI (n = 21) de FSH/LH, iniciando-se no décimo dia do ciclo estral, em 8 aplicações decrescentes, durante quatro dias consecutivos. Foi aplicado PGF2alfa concomitante com a quinta subdose de FSH/LH e realizadas duas inseminações artificiais às 12 e às 24 horas após o início dos sintomas de estro. As colheitas dos embriões foram realizadas 6,5 dias após a primeira inseminação artificial. Pelo exame ultra-sonográfico, avaliaram-se os números de folículos no momento da inseminação artificial (15,12; 15,76; e 14,94) e de corpos lúteos (10,68; 11,55; e 10,81) no dia da colheita, encontrando 5,20; 1,81; e 2,76 embriões viáveis, respectivamente, para 300 UI, 400 UI e 500 UI de FSH/LH. O grupo de 300 UI de FSH/LH apresentou os melhores resultados em relação aos embriões viáveis. Dos 106 embriões congelados pelo método one-step em 1...

Superovulation and embryo production in Bubalus bubalis); SUPEROVULAÇÃO OVARIANA E PRODUÇÃO DE EMBRIÕES EM Bubalus bubalis

LIPINSKI, L.C.; KOZICKI, L.E.; MARTINEZ, J.L.; PIASECKI JUNIOR, S.J.; SEGUI, M.S.; WEISS, R.R.
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 15/08/2006 POR
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37.64%
The aim of the present research work was to optimize ovarian superovulation rate and the embryo production in Murrah and Mediterranean buffaloes around the 60th day after parturition. Fourteen animals were divided in two groups of 7 animals each, G1 (treated animals) and G2 (untreated animals). All animals were subjected to a step of oestrus synchronization by receiving at the 0 day (OD) a vaginal pressary with progestagen (CIDR-B, Intervet), followed by the administration, in the morning of the day 1 (D1), of 3 mg stradiol benzoate IM (Estrogin, Farmavet, SP). The ovarian superovulation (SO) was carried out daily, at intervals of 12 hours in the morning and the afternoon by means of the administration of follicule stimulant hormone (FSH) (Pluset, Serono, Italy) in both groups of experimental animals, during four days according to the following protocol: at the 6th day, 75 IU; at the 7th day, 40 IU; at the 8th day, 30 IU; and at the 9th day, 20 IU. At the afternoon of the 8th day, administration of 500 µg of cloprostenol IM (Closin-Schering-Plough) was performed followed by the withdraw of the vaginal pessaries from all animals. Then, observations on the estrus of the experimental animals has been carried out. For this purpose the animals were inseminated twice at intervals of 12 hours. Additionaly...

Can repeated superovulation and embryo recovery in Boer goats limit donor participation in a MOET programme?

Lehloenya,K.C.; Greyling,J.P.C.; Grobler,S.
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 EN
Relevância na Pesquisa
37.34%
This study evaluated the effect of repeated superovulation and embryo recovery in 15 Boer goat does. Does were synchronised for oestrus using CIDR's for 17 days and superovulated with pFSH during the natural breeding season (autumn). Cervical inseminations with fresh undiluted semen were performed 36 h and 48 h following CIDR removal and the embryos surgically flushed six days after the second AI. Does superovulated for the first time recorded a shorter mean (± s.e.) induced duration of oestrus (20.8 ± 1.0 h), when compared to those repeatedly superovulated (30.4 ± 6.7 h). The mean (±s.e.) number of structures and embryos recovered were significantly lower in does treated repeatedly (6.0 ± 1.7 and 3.8 ± 1.7) than does superovulated for the first time (12.9 ± 0.5 and 11.7 ± 0.5), respectively. The mean (±s.e.) number of unfertilised ova per donor was significantly higher in repeatedly superovulated does (5.5 ± 1.6), compared to does superovulated for the first time (0.1 ± 0.1). The fertilisation rate and the number of transferable embryos were significantly lower in does treated repeatedly, compared to does superovulated for the first time. These results indicate that the number of times that a Boer goat doe can be utilised as the embryo donor may be limited to three times.