Effects of hormonal treatments on reproductive performance and embryo production

Thatcher, W.W.; Moreira, Frederico Rafael; Santos, J.E.P.; Mattos, R.C.; Lopes, Fernanda; Pancarcı, Şükrü Metin; Risco, C.A.

doi:10.1016/s0093-691x(00)00447-7

Cited by 133 publications

(76 citation statements)

References 30 publications

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“…During early luteal phase, inadequate or low progesterone levels generally cause to strike against embryonic development (Nephew et al 1991). For this reason, progesterone from corpus luteum is needed for embryonic implantation and development in uterus (Thatcher et al 2001) or exogenous progesterone applications may be needed to continue these vital processes for embryo (Davies and Beck 1992;Nephew et al 1994;Rostami et al 2017).…”

Section: Introductionmentioning

confidence: 99%

Effect of double GnRH injections on reproductive parameters in Awassi ewes receiving long-term progesterone

Zonturlu

Kaçar

Kaya

et al. 2018

Journal of Applied Animal Research

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The aim of this study was to investigate the effect of single or double Gonadotropin releasing hormone (GnRH) injections at the time of mating and following on day 9 on pregnancy rates and litter size in ewes. Oestrus was synchronized in 130 adult ewes using intravaginal sponges containing 20 mg of fluorogestone acetate for 14 days. All ewes received 10 IU/kg of pregnant mare serum gonadotropin (PMSG) at the sponge withdrawal. Then animals were divided into three groups. Ewes in group 1 (G1; Control, n = 68) received 1 ml placebo injection. In group 2 (G2; n = 30), ewes in oestrus were treated with 1 ml GnRH (4 μg/ml) at the time of mating. In group 3 (G3; n = 32), ewes were injected 1 ml GnRH not only at the time of mating but also on day 9 post-mating. There was significantly higher in duration of oestrus G1 compared with the G2 and G3. Pregnancy rate was found to be higher in G3 (96.0%) than in G1 (72.7%) and G2 (83.3%). The litter size was significantly higher for G3 (1.26 ± 0.14) in comparison with the G1 (1.18 ± 0.07) and G2 (1.22 ± 0.10). In conclusion, Post-mating GnRH injection enhanced the pregnancy rate and litter size, because of its beneficial effects on embriyo viability by increasing luteal formations. ARTICLE HISTORY

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Section: Introductionmentioning

confidence: 99%

Effect of double GnRH injections on reproductive parameters in Awassi ewes receiving long-term progesterone

Zonturlu

Kaçar

Kaya

et al. 2018

Journal of Applied Animal Research

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“…É possível que o rbST melhore a maturação nuclear e citoplasmática dos oócitos (Bevers et al, 1997;Izadyar et al, 1997, Bevers &Izadyar, 2002. Além disso, o tratamento das doadoras de embriões com rbST reduz a proporção de oócitos não-fecundados e aumenta o número de embriões transferíveis (Thatcher et al, 2001).…”

Section: Resultsunclassified

Efeito da somatotropina na população folicular, recuperação de oócitos e produção in vitro de embriões em vacas Gir

et al. 2007

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RESUMO -Avaliou-se o efeito da pré-estimulação ovariana com somatotropina bovina recombinante (rbST), associada ou não ao FSH, sobre a população folicular, a recuperação de oócitos e a produção in vitro de embriões em vacas Gir. Utilizaram-se vacas não-lactantes, em boas condições reprodutiva e corporal, cujo ciclo estral foi sincronizado pela administração de 0,5 mg de cloprostenol. Durante o experimento, as vacas receberam continuamente implantes auriculares de norgestomet, renovados a cada 14 dias, e, posteriormente, foram submetidas aos tratamentos: T1 ou controle -punção sem tratamento pré-estimulatório; T2 -aplicação única de 160 mg de rbST antes de cada punção; e T3 -punção após o tratamento com 160 mg de rbST em aplicação única, seguida de administração de 250 UI de FSH em doses decrescentes. Os oócitos foram maturados e fertilizados in vitro e os presumíveis zigotos foram cultivados por 192 horas pós-fertilização. Os tratamentos não foram diferentes quanto à população folicular presente no ovário. Entretanto, com a administração de 250 UI de FSH (T3), verificou-se aumento no diâmetro do maior folículo e no número de folículos grandes e médios e diminuição no número de folículos pequenos. A taxa de recuperação não diferiu entre o tratamento controle e T3 (com administração de FSH), mas foi menor no T2 (aplicação, em dose única, de 150 mg de rbST antes de cada punção). O número de oócitos de grau 1 foi maior e o de degenerados, menor no T3 em relação ao T1 e ao T2. O rbST (T2) aumentou a taxa de clivagem e a produção de blastocistos e, quando associado ao FSH, melhorou a qualidade dos oócitos nos animais Gir.Palavras-chave: bovinos, Gir, punção folicular, rbST Effect of somatotropin on follicular population, oocyte retrieval and in vitro embryo production in Gir cowsABSTRACT -The aim of this study was to evaluate ovarian pre-stimulation using recombinant bovine somatotropin (rbST) or rbST associated to FSH on follicular population, oocyte retrieval and in vitro embryo production in Gir cows (Bos indicus). Estrous cycle of non-lactating cycling cows with similar body and reproductive conditions were synchronized with cloprostenol followed by norgestomet ear implants, replaced every fourteen days. The animals were randomly distributed in three treatments: TI or control (punctured without pre-stimulation), TII (injection of 160 mg of rbST, before each aspiration) and TIII (injection of 160 mg of rbST followed by administration of 250 U.I. of FSH, before each aspiration). Oocytes were maturated and fertilized in vitro and presumptive zygotes were cultured in vitro for 192 hours post-fertilization. Treatments did not differ for ovarian follicular population. However, an increase in the diameter of the largest follicle and in the number of large and medium follicles with reduction in the number of small follicles was observed for TIII. Oocyte recovery did not differ between TI and TIII, but recovery rate was lower for TII. The number of grade I oocytes was higher and the number of degenerated oocytes was lower ...

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“…However, ovarian responsiveness to gonadotropins remains highly variable among individuals, and such unpredictability has become a major limiting factor for the development of embryo transfer (Mapletoft et al, 2002;Mapletoft and Hasler, 2005). Although several sources of this variability have been identified, including follicle stage, age, parity, and nutritional and gonadotropin reparation (Kafi and McGowan, 1997;Thatcher et al, 2001;Bó et al, 2002;Mossa et al, 2007;Malhi et al, 2008), no significant improvement in the superovulatory response has been observed since the early 1990s (Cory et al, 2013). The candidate gene approach has been widely used in genetic association and biomarker studies in animals and humans (Tabor et al, 2002).…”

Section: Introductionmentioning

confidence: 99%

Polymorphism of the inhibin βA gene and its relationship with superovulation traits in Chinese Holstein cows

Chen

Yang

2014

Genet. Mol. Res.

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ABSTRACT. Inhibin is a major regulator of secretion of folliclestimulating hormone, which is involved in follicular development and regulation of steroidogenesis in females. The objectives of this study were to detect polymorphisms of the bovine inhibin beta-A subunit (INHβA) gene and to evaluate its associations with superovulatory responses in 171 Chinese Holstein cows treated for superovulation. Polymerase chain reaction-restricted fragment length polymorphism revealed a C>T transition determining the StyI polymorphism at position 7639 in intron I of the bovine INHβA gene, and three genotypes (CC, CT, and TT) were detected. The frequencies of the three genotypes showed a tendency for CT > TT > CC, and this polymorphism was in Hardy-Weinberg equilibrium. Statistical analysis revealed no significant differences of least square means for superovulation traits among the three genotypes (P > 0.05). These results demonstrate, for the first time,

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Effects of hormonal treatments on reproductive performance and embryo production

Cited by 133 publications

References 30 publications

Effect of double GnRH injections on reproductive parameters in Awassi ewes receiving long-term progesterone

Effect of double GnRH injections on reproductive parameters in Awassi ewes receiving long-term progesterone

Efeito da somatotropina na população folicular, recuperação de oócitos e produção in vitro de embriões em vacas Gir

Polymorphism of the inhibin βA gene and its relationship with superovulation traits in Chinese Holstein cows

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