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2.
Reprod Domest Anim ; 59(8): e14688, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39115242

RESUMO

This study evaluated the use of the GnRH agonist hormone, deslorelin, to control the follicular population before initiating multiple ovulation and embryo transfer (MOET) treatment. Twenty-four cross-bred Santa Inês ewes, aged between 2 and 4 years, were randomly assigned to either a control group (n = 11) or a treated group (n = 13). All ewes received an intravaginal device containing 60 mg of medroxyprogesterone acetate on day 0, and a new device on day 7, which remained in place until day 14. Additionally, the ewes were administered 125 µg of cloprostenol on day 7. The superovulatory treatment involved administering 200 mg of pFSH, divided into eight decreasing doses at 12-h intervals starting on day 12. On day 14, 300 IU of eCG was administered. In the deslorelin group, three doses of 100 µg of deslorelin were administered starting on day 3 after the insertion of the vaginal device, with subsequent doses given at 72-h and 144-h intervals. Natural mating was performed 36 h after the removal of the progesterone implant using males with proven fertility. Embryo collection took place on the 6th day after mating, and the recovered structures were quantified and evaluated for quality and developmental stage. Transrectal ultrasonography was conducted on days 12, 16 and 21 to evaluate the ovaries, specifically to assess the ovarian follicular population and the presence of the corpus luteum. Ewes in the control group had higher embryo recovery rates (p < .01) compared to the treated group (5.2 ± 0.8 vs. 1.1 ± 0.8), with differences observed primarily in the number of morulae. The number of corpus luteum observed during the laparotomy on day 21 was significantly higher (p < .01) in the control group (10.44 vs. 4.5 corpus luteum per ewe). Yet, the treated group had a significantly higher number of follicles (p < .05) on the first day of pFSH application (5.5 vs. 3.0 follicles per ewe). In conclusion, although the inclusion of deslorelin in the superovulation protocol resulted in increased synchronization of oestrus and follicle number, it did not lead to an increase in the number of corpus luteum or harvested embryos.


Assuntos
Transferência Embrionária , Hormônio Foliculoestimulante , Superovulação , Pamoato de Triptorrelina , Animais , Feminino , Pamoato de Triptorrelina/análogos & derivados , Pamoato de Triptorrelina/farmacologia , Pamoato de Triptorrelina/administração & dosagem , Superovulação/efeitos dos fármacos , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/administração & dosagem , Transferência Embrionária/veterinária , Cloprostenol/farmacologia , Cloprostenol/administração & dosagem , Gravidez , Ovário/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Carneiro Doméstico , Ovinos/fisiologia , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Gonadotropina/administração & dosagem , Acetato de Medroxiprogesterona/farmacologia , Acetato de Medroxiprogesterona/administração & dosagem
3.
Theriogenology ; 226: 343-349, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38964033

RESUMO

Two experiments evaluated the effect of different hormonal treatments to synchronize follicle wave emergence on follicle dynamics and pregnancies per AI (P/AI) in estradiol (E2)/progesterone (P4) timed-AI (TAI) protocols in lactating dairy cows. In Experiment 1, lactating, primiparous Holstein cows (n = 36) received a P4 releasing device (Day 0) and were allocated at random to one of the following three treatment groups: Group EB received 2 mg E2 benzoate (EB) intramuscularly (i.m.), Group EB + GnRH received 2 mg EB+20 µg buserelin (GnRH) i.m., or Group EB + P4 received 2 mg EB + 100 mg of injectable P4 (iP4) in oil i.m. All cows received 0.150 mg D-Cloprostenol on Days 7 and 8 followed by P4 device removal, 400 IU eCG and 1 mg ECP on Day 8. Daily ultrasound examinations revealed that although the interval from P4 device removal to ovulation was not affected by treatment, cows that received EB + GnRH had an earlier (P < 0.05) emergence of the new follicular wave (Day 2.6 ± 0.2) than the other two treatment groups (Days 3.5 ± 0.3 and 6.1 ± 0.3, for EB and EB + P4, respectively). In Experiment 2, 808 lactating cows were assigned randomly to the three treatments evaluated in Experiment 1, and all the cows were TAI to determine P/AI. Cows in the EB + GnRH group had greater P/AI (57.4 %, P < 0.01) than those in the EB (44.6 %) or EB + P4 (45.7 %) groups. In conclusion, the administration of GnRH, but not iP4, on the day of insertion of a P4 device improves P/AI in lactating dairy cows synchronized for TAI with an estradiol/P4-based protocol.


Assuntos
Estradiol , Sincronização do Estro , Hormônio Liberador de Gonadotropina , Inseminação Artificial , Lactação , Folículo Ovariano , Progesterona , Animais , Bovinos/fisiologia , Feminino , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , Lactação/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Progesterona/administração & dosagem , Progesterona/farmacologia , Estradiol/farmacologia , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Sincronização do Estro/métodos , Gravidez , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Gonadotropina/administração & dosagem , Busserrelina/farmacologia , Busserrelina/administração & dosagem
4.
JBRA Assist Reprod ; 28(3): 521-525, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38875134

RESUMO

Non-obstructive azoospermia (NOA) is the most severe form of male factor infertility. It results form from either primary or secondary testicular failure. Here, we report cases of two patients with NOA due to maturation arrest and increased serum FSH, treated with GnRH agonist and gonadotrophins. The two NOA patients underwent a pharmacological treatment consisting of pituitary desensibilization using a GnRH agonist and testicular stimulation using menotropin. Testicular stimulation started one month after the beginning of GnRH agonist treatment. The female partner underwent controlled ovarian stimulation (COS) followed by intracytoplasmic sperm injection (ICSI). On the third day of the cycle, menotropin daily doses was administered. When at least one follicle ≥14 mm was visualized, pituitary blockage was performed using GnRH antagonist ganirelix. When three or more follicles attained a mean diameter of ≥17 mm, triptorelin acetate was administered to trigger final follicular maturation. Oocyte retrieval was performed 35 hours later. After treatment, male partner blood levels of the FSH, LH, decreased and total testosterone were increased. Spermatozoa was observed after semen collection in both cases. After COS, oocytes were retrieved and ICSI was performed. Embryos were biopsied for preimplantation genetic testing (PGT) and those considered euploidy were transferred resulting in positive implantation, ongoing pregnancy, and livebirth on both cases. In this report we present a successful strategy for hypergonadotropic hypogonadism AOA men, as an alternative approach to the surgical testicular sperm recovery. Nevertheless, prospective randomized trials are needed to confirm our findings.


Assuntos
Azoospermia , Hormônio Liberador de Gonadotropina , Hipogonadismo , Feminino , Humanos , Masculino , Gravidez , Azoospermia/tratamento farmacológico , Hormônio Liberador de Gonadotropina/agonistas , Gonadotropinas/uso terapêutico , Hipogonadismo/tratamento farmacológico , Nascido Vivo , Indução da Ovulação/métodos , Injeções de Esperma Intracitoplásmicas
5.
Anim Reprod ; 21(2): e20240007, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903866

RESUMO

Reviewing the current state of knowledge on reproductive performance and productive traits in rams has many advantages. First, the compilation of this information will serve as a literature resource for scientists conducting research around the world and will contribute to the understanding of the data collected and interpreted by researchers on the different hormonal strategies used to improve reproductive performance in rams. Second, it will allow scientists to identify current knowledge gaps and set future research priorities in ram reproduction. Rams play an important role in the global flock economy, but their reproductive analysis has been limited in the use of hormonal technologies to increase the productivity of sheep flocks. In this review, we cite the most important works on six hormones that, in one way or another, modify the hypothalamus-pituitary-gonadal axis, at different doses, in and out of the reproductive season, breeds, application methods, among other factors. The overall aim is to increase the reproductive efficiency of rams in different scenarios and, in some cases, of other species due to the lack of limited information on rams.

6.
Anim Reprod ; 21(1): e20230123, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510564

RESUMO

The impact of GnRH treatment on the day of TAI in beef cows has received limited investigation, especially concerning its association with estrus expression. Consequently, two experiments were conducted to assess the potential of GnRH treatment on the day of TAI to enhance fertility according to the expression or not of estrus in beef cows. Experiment 1 aimed to determine ovulation rate and luteal function, while Experiment 2 aimed to determine the effect of the two GnRH treatment approaches on pregnancy rate. In Experiment 1, multiparous Brangus suckling cows (n = 17) were submitted to an 8-day TAI protocol. Estrus occurrence was evaluated based on chalk removal on D10 (TAI) and cows were assigned to receive GnRH (25µg lecirelin; im) according to the group: GnRH (n = 7), regardless of estrus expression; or selectGnRH (n = 10), only cows not detected in estrus. Ovulation rate occurring until 77h after IVD removal did not differ (p = 0.17) between GnRH (85.7%; 6/7) and selectGnRH (100%; 10/10). Also, corpus luteum size and serum progesterone concentration were not affected (p>0.05) by treatments. In Experiment 2, crossbred taurine suckled cows (n = 384) were submitted to the same protocol as described in Experiment 1 and were randomly allocated to GnRH or selectGnRH groups. There was no difference in P/AI between groups (selectGnRH = 55.6%; GnRH = 54.3%; p = 0.7) 30 days after TAI. As expected, there was a pronounced effect (p<0.0001) of estrus expression on P/AI (Estrus = 61.5%; No estrus = 33.0%), regardless of group. In summary, ovulation timing and rate and luteal function did not differ between groups. Also, GnRH administration only in cows that do not show estrus is recommended, considering hormone savings and similar conception rate.

9.
JBRA Assist Reprod ; 28(1): 21-26, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38224580

RESUMO

OBJECTIVE: hCG is commonly used as an ovulation trigger in IVF. Its usage is associated with OHSS. GnRH agonist is an alternative to hCG and is associated with reduced incidence of OHSS. This study compared the cycle outcomes of GnRH agonists with hCG as an ovulation trigger in IVF cycles. METHODS: The medical notes of 209 IVF cycles receiving GnRH agonist and hCG as ovulation trigger over 18 months were reviewed in this retrospective study. The number and quality of mature oocytes, the number and quality of embryos, pregnancy rates, and outcomes were compared using Independent T-test or One-way ANOVA for normal distribution. The Mann-Whitney test or Kruskal-Wallis test was used for not normally distributed. p<0.05 was considered statistically significant. RESULTS: The cycle outcomes of 107 GnRH agonist-trigger and 102 hCG-trigger were compared. The MII oocytes retrieved and 2PN count was significantly higher in the GnRH agonist trigger group (p<0.001). Clinical pregnancy rate and ongoing pregnancy were higher in the GnRH agonist trigger group but were not statistically significant. The GnRH agonist trigger group was associated with low OHSS than the hCG trigger group (n=2(1.9%) and n=12(11.8%) respectively, p=0.004). CONCLUSION: GnRH agonist trigger is an option as a final maturation trigger in high-responder women undergoing IVF or ICSI cycles.


Assuntos
Síndrome de Hiperestimulação Ovariana , Feminino , Humanos , Gravidez , Gonadotropina Coriônica/uso terapêutico , Fertilização , Fertilização in vitro , Hormônio Liberador de Gonadotropina , Malásia/epidemiologia , Oócitos , Síndrome de Hiperestimulação Ovariana/epidemiologia , Síndrome de Hiperestimulação Ovariana/prevenção & controle , Ovulação , Indução da Ovulação , Estudos Retrospectivos , Centros de Atenção Terciária
10.
JBRA Assist Reprod ; 28(1): 2-8, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-37850846

RESUMO

OBJECTIVE: Pre-treatment (PT) therapies in IVF are known to be used as pre-stimulation modality to improve cycle outcomes. This study aims to assess whether PT in GnRH antagonist cycles triggered with GnRH-agonist impact oocyte maturation response. METHODS: Data were retrospectively collected for patients who underwent GnRH antagonist cycle with agonist triggering with and without PT. The patients were allocated to groups according to their PT status. The primary outcome evaluated was suboptimal maturation response. Suboptimal maturation to trigger was defined as no oocyte upon retrieval when adequate response was expected. RESULTS: The study population included 196 patients who underwent GnRH antagonist cycle with agonist triggering. The study group included 69 patients who received PT. The control group included 127 patients with no PT. In univariate analysis, the PT group significantly displayed suboptimal response compared to the controls (p = 0.008). All the patients in the study group with suboptimal response (with or without hCG re-triggering) were treated with GnRH-agonist as PT. Basal and pre-trigger LH values were significantly lower in the study group compared to controls (p < 0.001). Multivariate regression analysis revealed that PT with GnRH agonist was a significant predictor for suboptimal response. CONCLUSIONS: Pre-treatment, and particularly the use of GnRH-agonist as PT in antagonist cycles triggered with agonist, increases the risk of suboptimal response to GnRH-agonist trigger. This might be explained by prolonged pituitary suppression, which lasts beyond the PT cessation.


Assuntos
Fertilização in vitro , Hormônio Liberador de Gonadotropina , Humanos , Estudos Retrospectivos , Indução da Ovulação , Oogênese , Oócitos , Gonadotropina Coriônica
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