College of Life Science and Agricultural Engineering, Nanyang Normal University, Nanyang, Henan, China.
Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and technology, Northwest A&F University, Yangling, Shaanxi, China.
Reprod Domest Anim. 2023 Jun;58(6):851-859. doi: 10.1111/rda.14358. Epub 2023 Apr 16.
This study explored the specific molecular mechanisms through which repeated estrus synchronization (ES) treatments reduce the reproductive performance of dairy goats. Ninety-six goats (n = 24/group) were randomly assigned to two groups receiving ES treatments thrice every fortnight (3-equine chorionic gonadotropin [eCG] and 3-follicle stimulating hormone [FSH] groups) and two groups receiving one ES treatment (1-eCG and 1-FSH groups). ES treatments of 1- and 3-eCG goats were performed via the intravaginal insertion of a controlled internal drug release (CIDR) device containing 300 mg progesterone (P4), followed by 300 IU eCG injections 48 h before CIDR withdrawal. The 1- and 3-FSH goats received CIDR for 10 days, followed by 50 IU FSH and 100 μg PGF2α within 12 h of CIDR withdrawal. Ovaries of three goats in estrus from both groups were harvested for analysis. Subsequently, all the goats in estrus were artificially inseminated twice. Consequently, 3-eCG and 3-FSH goats showed a considerably reduced estrus rate and litter size than 1-eCG and 1-FSH goats. AQP3 mRNA and protein expression were significantly higher in the 3-eCG and 3-FSH groups than in the 1-eCG and 1-FSH groups. AQP3 overexpression led to cell apoptosis and decreased steroid hormone secretion ability of ovarian granulosa cells. Moreover, it resulted in a decrease in maturation and cleavage rates after parthenogenetic activation and in vitro fertilization, respectively. AQP3 gene was involved in reducing the reproductive performance of repeated ES-treated dairy goats. These findings provide a theoretical foundation for the effective use of reproductive hormones in breeding techniques for livestock.
本研究旨在探讨重复发情同步（ES）处理降低奶山羊繁殖性能的具体分子机制。96 只山羊（n=24/组）被随机分为两组，分别接受每隔两周重复 3 次 ES 处理（3 次马绒毛膜促性腺激素[eCG]和 3 次促卵泡激素[FSH]组）和接受 1 次 ES 处理（1 次 eCG 和 1 次 FSH 组）。1-eCG 和 3-eCG 组山羊通过阴道插入含有 300mg 孕酮（P4）的控释宫内节育器（CIDR）装置，然后在 CIDR 撤去前 48 小时注射 300IU eCG。1-FSH 和 3-FSH 组山羊接受 CIDR 处理 10 天，然后在 CIDR 撤去后 12 小时内注射 50IU FSH 和 100μg PGF2α。两组发情的 3 只山羊的卵巢被采集用于分析。随后，所有发情的山羊都进行了两次人工授精。结果，3-eCG 和 3-FSH 组的发情率和产仔数明显低于 1-eCG 和 1-FSH 组。AQP3 mRNA 和蛋白表达在 3-eCG 和 3-FSH 组明显高于 1-eCG 和 1-FSH 组。AQP3 过表达导致卵巢颗粒细胞凋亡和类固醇激素分泌能力下降。此外，它分别导致孤雌激活和体外受精后的成熟率和卵裂率降低。AQP3 基因参与降低重复 ES 处理奶山羊的繁殖性能。这些发现为在畜牧业繁殖技术中有效利用生殖激素提供了理论基础。
