Laboratory of Veterinary Reproduction, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
J Reprod Dev. 2021 Apr 21;67(2):83-88. doi: 10.1262/jrd.2020-126. Epub 2021 Jan 29.
Estrus synchronization requires multiple treatments of hormonal drugs, requiring considerable time and cost. The aim of the present study was to develop an estrus synchronization protocol using intravaginal administration of estradiol benzoate (EB) capsules in goats. Two types of capsules were prepared: an EB capsule that melted immediately after administration and a sustained-release (SR) EB capsule that dissolved slowly and reached a peak after 24 h. Goats with functional corpus lutea were intramuscularly treated with prostaglandin F (PG). At 24 h after PG administration, goats were administered 1 mg of EB solution intramuscularly (PG + 24IM; n = 6) or 1 mg of EB capsule intravaginally (PG + 24EB; n = 6). The SR EB capsule was administered intravaginally at the time of PG administration (PG + SR; n = 6). The control group (n = 6) received only PG. All groups showed estrus within 72 h after PG administration. The onset of estrus did not differ significantly between the PG + 24IM and PG + SR groups but was earlier than in the control group. Estradiol concentration in the PG + SR group peaked at 11.5 ± 6.1 h after EB and PG administration. Peak estradiol concentrations were not significantly different between the PG + 24IM and PG + SR groups (78.0 ± 25.8 and 64.0 ± 38.1 pg/ml, respectively), and were higher than the PG + 24EB and control groups (27.3 ± 8.8 and 14.6 ± 6.1 pg/ml, respectively). These results suggest that intravaginal administration of an EB capsule with a sustained-drug release base is applicable for estrus synchronization, as an alternative to intramuscular administration.
发情同步需要多次使用激素药物治疗，需要相当多的时间和成本。本研究的目的是开发一种使用苯甲酸雌二醇（EB）阴道胶囊在山羊中进行发情同步的方案。制备了两种类型的胶囊：一种是给药后立即融化的 EB 胶囊，另一种是缓慢溶解并在 24 小时后达到峰值的缓释（SR）EB 胶囊。有功能黄体的山羊接受前列腺素 F（PG）肌内注射。在 PG 给药后 24 小时，山羊肌内注射 1 毫克 EB 溶液（PG + 24IM；n = 6）或阴道内给予 1 毫克 EB 胶囊（PG + 24EB；n = 6）。PG 给药时阴道内给予 SR EB 胶囊（PG + SR；n = 6）。对照组（n = 6）仅接受 PG。所有组在 PG 给药后 72 小时内均出现发情。PG + 24IM 和 PG + SR 组发情开始时间无显著差异，但早于对照组。PG + SR 组雌二醇浓度在 EB 和 PG 给药后 11.5 ± 6.1 小时达到峰值。PG + 24IM 和 PG + SR 组之间的雌二醇浓度峰值无显著差异（分别为 78.0 ± 25.8 和 64.0 ± 38.1 pg/ml），高于 PG + 24EB 和对照组（分别为 27.3 ± 8.8 和 14.6 ± 6.1 pg/ml）。这些结果表明，阴道内给予具有持续药物释放基底的 EB 胶囊适用于发情同步，可替代肌内给药。
