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Progesterone production in superovulated holstein heifers and in crossbred recipient of embryo supplemented with betacarotene and tocopherol; Produção de progesterona em novilhas Holandesas superovuladas e receptoras de embrião mestiças suplementadas com betacaroteno e tocoferol

SALES, José Nélio de Sousa; DIAS, Lilian Mara Kirsch; FRANCI, Celso Rodrigues; ROCHA, Alexandro Aluísio; CARDOSO, Guilherme Gastão; SOUZA, José Camisão de
Fonte: Editora da Universidade Federal de Lavras Publicador: Editora da Universidade Federal de Lavras
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.17%
Two experiments were conducted to evaluate the effect of the intramuscular injection of betacarotene associated to tocopherol on the plasma concentration progesterone of superovulated Holstein heifers (experiment 1) and in crossbred (Bos taurus x Bos indicus) heifers submitted to fixed-time embryo transfer (FTET, experiment 2). In experiment 1, after estrus synchronization and superovulation animals were inseminated 12 and 24 hours after estrus onset and embryos flushed 7 days later. Heifers were allocated randomly to one of three treatments: Control; T800 (800 mg of betacarotene plus 500 mg of tocopherol) and T1200 (1,200 mg of betacarotene plus 750 mg of tocopherol). The treatments were given on the day of ear implant placement and repeated on the first day of superovulation. Blood samples were collected on D0, D5, D9, D12 and D16. In experiment 2, treatments were imposed at intravaginal device insertion (D0). The same experimental design, as in experiment 1, was used. Blood samples were collected on D17 (embryos implanted) for progesterone determination by radioimmunoassay. In experiment 1, average plasma progesterone concentrations after corpora lutea formation (D12 plus D16 means) were 13.7±1.8 ng/ml, 14.5±2.3 ng/ml and 10.8±2.3 ng/ml for control...

Influência da receptora e do embrião sobre a viabilidade embrionária e sexo determinados através da ultra-sonografia ; Influence of the recipient and embryo on embryonic viability and sex determined by ultrasonografic exam

Mello, Valérya Fernandes
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 15/12/2003 PT
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Este trabalho foi conduzido com a finalidade de se verificar a influência da receptora e do embrião sobre o índice de prenhez (IP) e proporção de sexo. Um total de 431 embriões produzidos in vitro foram transferidos não cirurgicamente para o corno uterino de receptoras mestiças, previamente sincronizadas, de acordo com o desenvolvimento embrionário e grau de qualidade do embriâo. O primeiro exame de diagnóstico de prenhez (DP) foi realizado aos 26-28 dias da transferência e o segundo, aos 50-52 dias, quando foram também realizadas as avaliações das receptoras e a determinação do sexo dos fetos através da ultra-sonografia. O índice de prenhez foi de 38,0% (164/431) para o primeiro DP e 92,1% (151/164) das receptoras permaneceram prenhes aos 50-52 dias, evidenciando 7,9% (13/164) de perdas embrionárias e/ou fetais entre os exames. Maiores índices de prenhez (P<0,05) foram obtidos para embriões classificados como de grau 1 (86,5%) e desenvolvimento embrionário ao estágio de blastocisto expandido (Bx; 40,1%). A avaliação das receptoras revelou maior ocorrência de corpos lúteos (CL) no ovário direito (65,1% vs. 34,9%), contudo, sem influenciar no IP, com 92,8% e 88,5% de prenhez, respectivamente, para CL no ovário direito e esquerdo. O tipo de CL (grau 1...

Emprego de um novo dispositivo intravaginal para liberação sustentada de progesterona em programas de TETF em receptoras de embrião (Bos taurus taurus x Bos taurus indicus); Use of a new intravaginal device for releasing progesterone-based ETFT program in embryo recipients (Bos taurus taurus x Bos taurus indicus)

Pardo, Fernando José Delai
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 27/06/2008 PT
Relevância na Pesquisa
36.17%
Dentre os inúmeros fatores para o sucesso dos programas de TE, as receptoras merecem grande destaque por serem fator determinante no sucesso desta biotecnologia. Atualmente, os produtos de liberação de progesterona disponíveis no mercado brasileiro são importados e confeccionados a base de nylon e silicone. O silicone é uma matriz biocompatível, mas não biodegradável, contrariamente aos novos dispositivos que utilizam biopolímeros obtidos a partir da fermentação bacteriana da cana-de-açúcar. O presente experimento tem como objetivo estudar a eficiência do novo dispositivo intravaginal de liberação sustentada de progesterona no programa de TETF, em novilhas e vacas cruzadas, pela avaliação das taxas de aproveitamento, concepção e de prenhez. O experimento foi realizado em parceria com a empresa de Embryo-sys®, a qual foi responsável por realizar a sincronização das receptoras, assim como das inovulações. As sincronizações e as inovulações foram realizadas em três propriedades nos municípios de Paranapanema-SP, Itapetininga-SP e Ouro Fino-MG. Todos os animais foram submetidos a rigoroso manejo sanitário e ginecológico, e mantidos a pasto (Brachiaria decumbens) com suplementação mineral e água ad libitum. As receptoras (n = 205) foram agrupadas equitativamente quanto ao escore de condição corporal...

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
36.36%
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...

Suplementação de vacas receptoras de embiões com ácidos graxos pollinsaturados esteríficados; Supplementation of embryo recipients cows with esterificated polyunsatured fatty acids

Cardona, Juan Camilo Angel
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
36.54%
Foi realizado um experimento para avaliar os efeitos da inclusão de ácidos graxos poliinsaturados (PUFA) em suplementos isoenergéticos, fornecidos a novilhas receptoras de embriões, sobre o desempenho produtivo e reprodutivo e sobre alguns parâmetros plasmáticos. Os três tratamentos avaliados foram: suplemento funcional onde as novilhas receberam suplemento contendo 150 gr de sabões cálcicos de PUFA (Megalac-E®), suplemento energético onde as novilhas receberam um suplemento sem a inclusão de sabões cálcicos e sem suplementação. O período experimental teve uma duração de 60 dias sendo que a suplementação iniciou 30 dias antes da transferência dos embriões e acabou com a confirmação da prenhez. Foram utilizadas 44 novilhas cruzadas Angus*Hereford de dois anos de idade e peso médio no inicio do experimento de 385±36 kg, mantidas num mesmo piquete de campo nativo melhorado e suplementadas diariamente de forma individual. As novilhas foram pesadas a cada 28 dias e a sincronização do estro foi realizada utilizando duas doses de PGF2 com um intervalo de 11 dias. Sete dias após a detecção do cio foi realizada a medição do corpo lúteo e a transferência dos embriões. Amostras de sangue foram coletadas no dia da transferência dos embriões e no dia da confirmação de prenhez. O tipo de suplemento utilizado não afetou as variaveis de comportamento reprodutivo...

Associations among milk production and rectal temperature on pregnancy maintenance in lactating recipient dairy cows

Vasconcelos, J. L. M.; Cooke, R. F.; Jardina, D. T. G.; Aragon, F. L.; Veras, M. B.; Soriano, S.; Sobreira, N.; Scarpa, A. B.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 140-147
ENG
Relevância na Pesquisa
36.27%
The objective of this study was to evaluate the associations among milk production, rectal temperature, and pregnancy maintenance in lactating recipient dairy cows. Data were collected during an 11-mo period from 463 Holstein cows (203 primiparous and 260 multiparous) assigned to a fixed-time embryo transfer (ET) protocol. Only cows detected with a visible corpus luteum immediately prior to ET were used. Rectal temperatures were collected from all cows on the same day of ET. Milk production at ET was calculated by averaging individual daily milk production during the 7 d preceding ET. Pregnancy diagnosis was performed by transrectal ultrasonography 21 d after ET. Cows were ranked and assigned to groups according to median milk production (median = 35 kg/d; HPROD = above median; LPROD = below median) and rectal temperature (<= 39.0 degrees C = LTEMP; >39.0 degrees C = HTEMP). A milk production x temperature group interaction was detected (P = 0.04) for pregnancy analysis because HTEMP cows ranked as LPROD were 3.1 time more likely to maintain pregnancy compared with HTEMP cows ranked as HPROD (P = 0.03). Milk production did not affect (P = 0.55) odds of pregnancy maintenance within LTEMP cows, however, and no differences in odds of pregnancy maintenance were detected between HTEMP and LTEMP within milk production groups (P > 0.11). Within HTEMP cows...

Effects of timing of induced luteolysis in embryo donor mares on reproductive performance and pregnancy rate in recipient mares

Goretti, R. G.; Araujo, R. R.; Rocha Filho, A. N.; Araujo, G. H. M.; Lopes, E. P.; Guimaraes, J. D.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 1170-1174
ENG
Relevância na Pesquisa
36.64%
The objective was to evaluate the effects of giving prostaglandin F(2 alpha) (PGF) to donor mares 48 h prior to embryo collection. Non-lactating donor mares (n = 20 estrous cycles in 10 mares), ranging from 2.5 to 10 y of age and 400 to 500 kg of body weight were used from September 2004 to February 2005 in the southern hemisphere (Brazil). Donor mares were randomly assigned in a cross-over design study. During a Treated cycle, 7.5 mg PGF was given 48 h prior to embryo collection, whereas in the Control cycle, 7.5 mg PGF was given at embryo collection. In Treated Cycles, serum progesterone concentrations decreased between the day of PGF treatment and the day of embryo collection (13.9 +/- 5.4 and 0.5 +/- 0.3 ng/mL, respectively; P < 0.05). In Treated versus Control cycles, the interovulatory interval was shorter (14.9 +/- 0.9 vs 17.5 +/- 1.1 d, P < 0.05). However, there was no significant difference between these groups for the interval from PGF to ovulation (average, 9.8 d), embryo recovery rate (average, 75%), embryo quality, uterine protein concentration, and pregnancy rate in recipient mares (average, 87% at 15 d after ovulation, with no pregnancy loss detected by 60 d). In conclusion, giving donor mares PGF 48 h prior to embryo collection reduced the average interovulatory interval by approximately 2.5 d...

Description and genetic analysis of three sets of monozygotic twins resulting from transfers of single embryos to recipient mares

Mancill, Semira S.; Blodgett, Glenn; Arnott, Robert J.; Alvarenga, Marco; Love, Charles C.; Hinrichs, Katrin
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1040-1043
ENG
Relevância na Pesquisa
36.73%
Case Description-3 sets of monozygotic twins resulting from transfers of single embryos to recipient mares were examined. Clinical Findings-In all 3 recipient mares with twin pregnancies, only 1 embryonic vesicle was detected before day 25 of gestation. In 1 recipient mare, 2 apparent adjacent vesicles, each containing an embryo with a heartbeat, were visualized on ultrasonographic examination on day 37 of gestation. The other 2 recipient mares underwent ultrasonographic examination on day 30 of gestation, at which time only 1 vesicle and embryo was identified. In these latter 2 recipient mares, however, a thorough ultrasonographic examination for a second conceptus on day 30 had not been performed, as only 1 embryo had been transferred and visualized on early ultrasonographic examination. Treatment and Outcome-All twin pregnancies resulted in death of both fetuses. Genetic analysis confirmed that each set of monozygotic twins originated from the transferred embryo. Clinical Relevance-Monozygotic twin pregnancy may occur after embryo transfer; thus recipient mares should be examined thoroughly for multiple conceptuses, especially between 25 and 30 days of gestation. At this time, the allantoides of monozygotic twins should be visible ultrasonographically and effective management may still be possible.

Use of long-acting progesterone to acyclic embryo recipient mares

Greco,Gabriel Maksoud; Burlamaqui,Fábio Luis Gonçalves; Pinna,Aline Emerim; Queiroz,Fernando José Rohen de; Cunha,Maria Pia dos Santos; Brandão,Felipe Zandonadi
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2012 EN
Relevância na Pesquisa
46.64%
The objective of this study was to evaluate the efficiency of cyclic and acyclic progesterone-treated recipient mares in a commercial embryo transfer program. Acyclic recipients were treated with decreasing amounts of estradiol cypionate (ECP® - Pfizer Saúde Animal, São Paulo, Brazil), followed by 1500 mg of a sustained-release progesterone injection (P4LA150® - Laboratórios B.E.T., Rio de Janeiro, Brazil). Out of all 1506 embryo recovery attempts performed, 59.36% were positive (894/1506). Pregnancy rates of cyclic and acyclic mares were, respectively, 44.12% (319/723) and 57.68% (139/241) - higher in acyclic recipients under progesterone treatment. Embryo loss was similar between groups (9.72% 31/319 vs. 11.51% - 16/139). When fertility data on acyclic mares treated with long-action progesterone were grouped in relation to the interval of the beginning of the treatment with progesterone to the embryo transfer, there was no difference in pregnancy rates at 12 days (51.28% - 20/39; 58.92% - 33/56; 60.52% - 46/76 and 58.57% - 41/70 for embryos transferred 3 (P3), 4 (P4), 5 (P5) and 6 (P6) days after the beginning of the treatment with progesterone). Groups P3, P4, P5 and P6 showed embryo loss rates of 20.00% (4/20), 12.12% (4/33)...

Embryo transfer in no cycling Crioula and Quarter horse breeds treated with estradiol cipionate and long-acting progesterone

Kaercher,Fernanda; Siqueira,Marlon; Mercadante,Alessandro; Figueiredo,Tatiana; Weiss,Romildo Romualdo; Siqueira,Felipe; Kozicki,Luiz Ernandes
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
Relevância na Pesquisa
36.6%
The aim of this work was to prepare the mares for embryo transfer. In group 1 (G1,treated, n=15), recipient mares in anoestrus or in a transition period were treated with 5.0, 3.0 and 2.0 mg of estradiol cipionate at the days 0, 1 and 2 respectively, beginning at the day of ovulation (DO). From the fourth day on, the mares this group received long-acting progesterone weekly, up to the 120 day of gestation. At D8, the embryo was collected from the donor and transferred to the recipient. At D12, the ultrasonographyc diagnosis of pregnancy was carried out. The control group (G2, not treated, n=20) was formed by cycling recipient mares, displaying ovulation at each 2 to 3 days after the donors mare ovulation. The pregnancy rate was higher (p<0.05) in the mares from G2 (85.0%) than from G1 (53.3%). Thus, it could be concluded that the treated mares although showed lesser pregnancy rate than the cycling mare, were satisfactory alternative to be used mainly when there is no available cycling recipient.

Efficiency of porcine somatic cell nuclear transfer – a retrospective study of factors related to embryo recipient and embryos transferred

Huang, Yongye; Ouyang, Hongsheng; Yu, Hao; Lai, Liangxue; Pang, Daxin; Li, Zhanjun
Fonte: The Company of Biologists Publicador: The Company of Biologists
Tipo: Artigo de Revista Científica
Publicado em 02/10/2013 EN
Relevância na Pesquisa
36.22%
The successful generation of pigs via somatic cell nuclear transfer depends on reducing risk factors in several aspects. To provide an overview of some influencing factors related to embryo transfer, the follow-up data related to cloned pig production collected in our laboratory was examined. (i) Spring showed a higher full-term pregnancy rate compared with winter (33.6% vs 18.6%, P = 0.006). Furthermore, a regression equation can be drawn between full-term pregnancy numbers and pregnancy numbers in different months (y = 0.692x−3.326). (ii) There were no significant differences detected in the number of transferred embryos between surrogate sows exhibiting full-term development compared to those that did not. (iii) Non-ovulating surrogate sows presented a higher percentage of full-term pregnancies compared with ovulating sows (32.0% vs 17.5%, P = 0.004; respectively). (iv) Abortion was most likely to take place between Day 27 to Day 34. (v) Based on Life Table Survival Analysis, delivery in normally fertilized and surrogate sows is expected to be completed before Day 117 or Day 125, respectively. Additionally, the length of pregnancy in surrogate sows was negatively correlated with the average litter size, which was not found for normally fertilized sows. In conclusion...

Embryo transfer cannot delineate between the maternal pregnancy environment and germ line effects in the transgenerational transmission of disease in rats

Tran, Melanie; Gallo, Linda A.; Hanvey, Alanna N.; Jefferies, Andrew J.; Westcott, Kerryn T.; Cullen-McEwen, Luise A.; Gardner, David K.; Moritz, Karen M.; Wlodek, Mary E.
Fonte: American Physiological Society Publicador: American Physiological Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
36.53%
Adverse conditions in utero can have transgenerational effects, in the absence of a subsequent insult. We aimed to investigate the contribution of the maternal pregnancy environment vs. germ line effects in mediating alterations to cardiorenal and metabolic physiology in offspring from mothers born small. Uteroplacental insufficiency was induced by bilateral uterine artery and vein ligation (Restricted group) or sham surgery (Control group) in Wistar-Kyoto rats. Restricted and control female offspring (F1) were mated with either breeder males (embryo donor) or vasectomized males (embryo recipient). Embryo transfer was performed at embryonic day (E) 1, whereby second-generation (F2) embryos gestated (donor-in-recipient) in either a control (Cont-in-Cont, Rest-in-Cont) or restricted (Cont-in-Rest, Rest-in-Rest) mother. In male and female offspring, glomerular number and size were measured at postnatal day (PN) 35, and systolic blood pressure, glucose control, insulin sensitivity, and pancreatic β-cell mass were measured in separate sibling cohorts at 6 mo. Rest-in-Rest offspring were hypothesized to have similar characteristics (reduced growth, altered metabolic control, and hypertension) to non-embryo-transferred Rest, such that embryo transfer would not be a confounding experimental influence. However...

Efeito da progesterona exógena na produção de embriões em novilhas leiteiras; Effect of exogenous progesterone on embryo production in dairy heifers

SANTOS, Klayto José Gonçalves dos
Fonte: Universidade Federal de Goiás; BR; UFG; Doutorado em Ciência Animal; Ciências Agrárias Publicador: Universidade Federal de Goiás; BR; UFG; Doutorado em Ciência Animal; Ciências Agrárias
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
36.29%
The reproductive and productive index of dairy cattle in Brazil are below the desirable rates, and, in recent decades, the increase in milk production occurred, partly, more because of the expansion of explored areas and the increase of herds than due to an effective productive increment. The development and application of reproductive biotechnologies are essential conditions for improving reproductive efficiency, especially for domestic ruminants, and techniques such as artificial insemination and embryo transfer have been successfully used. Other biotechnologies such as in vitro embryo production, cloning and genetic modification help to accelerate genetic improvement, because they include animals with superior desirable traits, although the results in terms of production are not so good. The main goal of an embryo transfer program is to obtain a high number of viable embryos per donor, after exogenous hormones administration, by increasing the number of oocytes released, enabling the embryo transfer to recipient cows in order to complete the gestation. Cows are born with more than 100,000 oocytes in ovarian follicles, but by natural via, only 0.01% of viable products can be generated, or a number close to 10 calves throughout their reproductive life. One of the proposed solutions to this problem was the development of in vitro production (IVP) of bovine embryos...

Development of in vitro embryo production systems for red deer (Cervus elaphus) - Part 3. In vitro fertilisation using sheep serum as a capacitating agent and the subsequent birth of calves

Berg, D.; Pugh, P.; Thompson, J.; Asher, G.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2002 EN
Relevância na Pesquisa
36.22%
The following experiments investigated the use of sheep serum (SS) as a capacitating agent for red deer (Cervus elaphus) sperm during in vitro fertilisation. Red deer oocytes were collected at slaughter and matured in vitro for 24h in TCM-199 supplemented with 10% foetal calf serum, 10 microg ml(-1) FSH and LH, and 1microg ml(-1) of oestradiol. Fertilisation medium was IVF-SOF modified to contain 5mM Ca(2+) and no glucose. Experiment 1 investigated the addition of heparin, BSA (8 mg ml(-1)) or 20% SS. All oocytes were penetrated when IVF-SOF was supplemented with SS compared to 10 and 0% penetration when either heparin or BSA was present (P<0.01). However, 43.8% of these oocytes were polyspermic when the medium contained SS. In Experiment 2, the effect of sperm concentration on penetration rates during in vitro fertilisation was investigated. Total sperm penetration and monospermic penetration rates increased with increased sperm concentrations in a log linear manner (P<0.001) and both approached an asymptote at 0.4 x 10(6) sperm ml(-1) with 93.6 and 77% for total and monospermic penetration, respectively. Polyspermic fertilisation also increased with increasing sperm concentrations (P<0.05) but was variable (range 3.5+/-4.2 to 42.3+/-10.6%)...

Heteroplasmy in bovine fetuses produced by intra and inter subspecific somatic cell nuclear transfer: Neutral segregation of nuclear donor mitochondrial DNA in various tissues and evidence for recipient cow mitochondria in fetal blood.

Hiendleder, S.; Zakhartchenko, V.; Wenigerkind, H.; Reichenbach, H.D.; Bruggerhoff, K.; Prelle, K.; Brem, G.; Stojkovic, M.; Wolf, E.
Fonte: Soc Study Reproduction Publicador: Soc Study Reproduction
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
Relevância na Pesquisa
36.35%
Varying degrees of mitochondrial DNA (mtDNA) heteroplasmy have been observed in nuclear transfer embryos, fetuses, and offspring, but the mechanisms leading to this condition are unknown. We have generated a clone of 12 bovine somatic cell nuclear transfer fetuses, using nuclear donor cells, recipient oocytes, and recipient heifers with defined mtDNA genotypes, to study nuclear-mitochondrial interactions and the origins of mtDNA heteroplasmy. Embryos were reconstructed from granulosa cells with Bos taurus mtDNA type A and recipient oocytes collected from three different maternal lineages with B. taurus mtDNA type B, B. taurus mtDNA type C, or B. indicus mtDNA. Sequence differences in the control region (CR) of B. taurus mtDNAs ranged from 6 to 11 nucleotides and differences between B. taurus and B. indicus CRs from 45 to 50 nucleotides. Fetuses were recovered from recipient heifers with B. taurus mtDNA type B on Day 80 after nuclear transfer (eight B. taurus A/B, two B. taurus A/C, and two B. taurus A/B. indicus). Agarose gel analysis of the CR by polymerase chain reaction-based restriction fragment length polymorphism failed to detect nuclear donor mtDNA in 11 investigated tissues of 10 viable fetuses and in DNA samples of two fetuses in resorption (one B. taurus A/B and one B. taurus A/C). A more sensitive analysis of 1801 plasmid clones with CR inserts derived from tissues of a B. taurus A/B. indicus fetus detected no or very low levels of heteroplasmy (0.5–0.7%). However...

Embryo-Maternal Communication in Bovine – Strategies for Deciphering a Complex Cross-Talk

Wolf, E.; Arnold, G.; Bauersachs, S.; Beier, H.; Blum, H.; Einspanier, R.; Frohlich, T.; Herrier, A.; Hiendleder, S.; Kolle, S.; Prelle, K.; Reichenbach, H.D.; Stojkovic, M.; Wenigerkind, H.; Sinowatz, F.
Fonte: Blackwell Wissenschafts-Verlag GMBH Publicador: Blackwell Wissenschafts-Verlag GMBH
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
Relevância na Pesquisa
36.32%
Early embryonic development, implantation and maintenance of a pregnancy are critically dependent on an intact embryo-maternal communication. So far, only few signals involved in this dialogue have been identified. In bovine and other ruminants, interferon tau is the predominant embryonic pregnancy recognition signal, exhibiting antiluteolytic activity. However, this is just one aspect of the complex process of embryo-maternal signalling, and a number of other systems are more likely to be involved. To gain a more comprehensive understanding of these important mechanisms, integrated projects involving specialists in embryology, reproductive biotechnology and functional genome research are necessary to perform a systematic analysis of interactions between pre-implantation stage embryos and oviduct or uterine epithelial cells, respectively. State-of-the-art transcriptomic and proteomic technologies will identify reciprocal signals between embryos and their maternal environment and the respective downstream reaction cascades. For in vivo studies, the use of monozygotic twins as recipient animals provides elegant model systems, thus eliminating genetic variability as a cause of differential gene expression. In addition, suitable systems for the co-culture of oviduct epithelial or endometrium cells with the respective embryonic stages need to be established for functional validation of candidate genes potentially involved in the dialogue between embryos and their maternal environment. The knowledge of these mechanisms should help to increase the pregnancy rate following embryo transfer and to avoid embryonic losses. Candidate genes involved in embryo-maternal communication will also be used to define new quality criteria for the selection of embryos for transfer to recipients. Another application is the supplementation of embryotrophic factors or components of embryo-maternal signalling in optimized formulations...

Influência do genótipo das receptoras de embriões bovinos (Bos taurus ou Bos indicus) sobre a taxa de gestação

Rebelo, Carolina Sant'ana da Silva
Fonte: Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária Publicador: Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária
Tipo: Trabalho de Conclusão de Curso
Publicado em //2008 POR
Relevância na Pesquisa
36.41%
Dissertação de Mestrado Integrado em Medicina Veterinária; O presente estudo teve como objectivo avaliar a influência do genótipo da receptora de embriões bovinos sobre a taxa de gestação. Foram utilizadas fêmeas bovinas da raça Nelore registadas na ABCZ (Associação Brasileira de Criadores de Zebu) de superioridade genética comprovada como dadoras de embriões. Para receptoras, seleccionaram-se 571 fêmeas bovinas em idade reprodutiva, cruzadas de genótipos Bos taurus e cruzadas de genótipos Bos indicus com condição corporal entre 3 e 4 (escala de 1 a 5). Todas as fêmeas utilizadas foram avaliadas quanto ao seu estado clínico-ginecológico, para verificar se estavam aptas ao processo de superovulação (dadoras) e à manutenção de uma possível gestação (receptoras). As receptoras foram divididas em dois grupos, tendo como principal critério a divisão dos genótipos entre as espécies Bos taurus e Bos indicus. Não houve diferença estatística (p>0,05) entre os grupos, pelo que a variavél genótipo da receptora não influenciou a taxa de gestação. Porém, a taxa de gestação foi influenciada por outros factores como o estádio de desenvolvimento do embrião e a dificuldade de passagem pelo cervix. Assim...

Ultrasonography of the conceptus development from days 15 to 60 of pregnancy in non-cyclic recipient mares

Silva,Elisa Sant'Anna Monteiro da; Pantoja,José Carlos de Figueiredo; Puoli,José Nicolau Próspero; Meira,Cezinande
Fonte: Universidade Federal de Santa Maria Publicador: Universidade Federal de Santa Maria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
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The present study evaluated the development of equine conceptus transferred to non-cyclic recipient mares treated with altrenogest. Twenty four mares were used as embryo recipients during the ovulatory phase (Control group; n=8) or anestrus/transitional phases (Altrenogest group; n=16) and were evaluated by transrectal ultrasonography, at five day intervals, to monitor the development of embryonic vesicles from 15 to 45 days of pregnancy and embryo proper/fetus from 20 to 60 days. Embryonic vesicle's features such as shape, embryo location within the vesicle and umbilical cord development were similar between cyclic and non-cyclic recipient mares. The embryonic vesicle and embryo proper/fetus growth was significant (P<0.05) between 15 and 60 days of gestation in Altrenogest and Control groups, except for days 20 to 30, where embryonic vesicle growth decrease was observed (P>0.05). The embryonic vesicle and embryo proper/fetus growth was similar (P>0.05) when gestational days were compared between groups. The similarity in conceptus growth between cyclic and non-cyclic recipient mares during early pregnancy indicates that the uterine environment of non-cyclic recipient mares treated with progestins provides similar conditions for the development of transferred embryos

Dinâmica folicular e taxa de prenhez em novilhas receptoras de embrião (Bos taurus indicus x Bos taurus taurus) tratadas com o protocolo "Ovsynch" para inovulação em tempo fixo; Follicular dynamics and pregnancy rate in embryo recipient (Bos taurus indicus x Bos taurus taurus) treated with "Ovsynch" protocol for fixed-time embryo transfer

Baruselli, Pietro Sampaio; Marques, Márcio de Oliveira; Carvalho, Nelcio Antonio Tonizza de; Berber, Rodolfo Cassimiro de Araújo; Valentim, Renato; Carvalho Filho, Ademário Fernandes de; Costa Neto, Waldyr Pinto
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 01/01/2003 POR
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56.62%
Objetivou-se avaliar a eficiência da sincronização da ovulação para inovulação em tempo fixo em novilhas Bos taurus indicus x Bos taurus taurus receptoras de embrião. No Experimento 1, a dinâmica folicular foi acompanhada durante o protocolo "Ovsynch" (G1; n=35) e após a aplicação de PGF2alfa (G2; n=34). No Experimento 2, os mesmos tratamentos foram realizados a campo em 168 (G1) e 177 (G2) novilhas. No D6, colheu-se sangue para dosagem de P4 e se realizaram exames ultra-sonográficos. No D7, realizou-se a inovulação. No Experimento 1, 45,7% dos animais ovularam após o 1º GnRH (P;0,05). Ao final, a taxa de prenhez no Gl foi de 35,7% e no G2 de 25,4% (P<0,05). Foram detectadas em estro 53,7% das novilhas do G2 e 33,3% do Gl (P<0,05). Os corpos lúteos com maior área determinaram maiores concentrações de P4 e taxa de concepção (P<0,05). A sincronização da ovulação para inovulação em tempo fixo aumentou as taxas de ovulação, de aproveitamento e de prenhez em novilhas receptoras de embrião.; The aim of this study was to evaluate the efficacy of the synchronization of ovulation for fixed-time embryo transfer in crossbred recipient heifers (Bos taurus indicus x Bos taurus taurus). At Experiment 1, ovarian ultrasonography was performed to evaluate follicular dynamics during the "Ovsynch" protocol (G1; n=35) or single PGF2alpha injection (G2; n=34). At Experiment 2...

Embryo transfer in angus and brahman recipient cows: Effect of two methods of estrus synchronization on induced estrus and pregnancy

Chase, Jr,Chad C; Vargas,Carlos A; Hammond,Andrew C; Olson,Timothy A; Griffin,James L; Murphy,Clifton N; Tewolde,Assefaw; Fields,Michael J
Fonte: UNIVERSIDAD DEL ZULIA Publicador: UNIVERSIDAD DEL ZULIA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2009 EN
Relevância na Pesquisa
36.44%
Over a 3-year period, 88 Angus and 87 Brahman cows were used as recipients to determine the effects of breedtype and method of estrous synchronization on induced estrus and subsequent pregnancy following embryo transfer. Estrus was synchronized in recipients using either prostaglandin-F2α (PGF; Lutalyse) or progestogen (PRO; Syncro-Mate-B). Recipients were treated (im) with PGF on day -11 (25 mg), 0 (12.5 mg), and 1 (12.5 mg). Recipients were treated with PRO on day -9 (6 mg norgestomet ear implant and 2 mL [im] of 3 mg of norgestomet and 5 mg of estradiol valerate) and the ear implant was removed on day 0. Embryos were randomly transferred to recipients synchronous +24 to -24 h with a 7-d embryo. Both synchronization methods (PGF vs. PRO) were similarly effective in inducing estrus (89.8 vs. 86.7%). Percentage of induced estrus was similar between Brahman (91.0%) and Angus (85.6%). Recipients treated with PGF had a longer (P = 0.001) interval to estrus than PRO treated recipients (77.4 vs. 60.1 h). Estrus response in Angus was earlier (P = 0.043) than in Brahman (65.4 vs. 72.2 h). Neither breed (P = 0.97; Angus 49% 35/72 and Brahman 54% 38/70) nor estrus synchronization treatment (P = 0.23; PRO 49% 35/72 and PGF 54% 38/70) affected pregnancy rate. Pregnancy rates in recipients closely synchronized (0 h) was 60.0%...