秦川牛发情周期内激素水平的变化以及胎次差异

The Variations in Hormone Levels during the Estrous Cycle in Qinchuan Cattle and Parity Differences

中文关键词: 生殖激素，青年牛，经产牛，发情周期，秦川牛

英文关键词: reproductive hormones  Yang Cows  Multiparous Cows  parity, estrous cycle  Qinchuan cattle.

中文摘要:

      肉牛繁殖力低下始终是制约产业发展的关键因素,尽管利用外源生殖激素调控发情周期可以提高繁殖力,但不同胎次的母牛在发情调控和超数排卵过程中对激素处理的响应存在差异。本研究采用ELISA方法测定激素水平,监测秦川牛发情周期内的促卵泡素(FSH)、促黄体素(LH)、雌二醇(E2)和孕酮(P4)浓度,比较青年牛与经产牛的激素水平差异。结果表明,在发情周期内,青年秦川牛的FSH浓度在第15天显著高于经产牛(P＜0.05), E2浓度在第0天和第20天显著高于经产牛(P＜0.05),P4浓度在第5天,第10天,第15天,第20天显著高于经产牛(P＜0.05),LH浓度在整个发情周期中均显著高于经产牛(P＜0.05)。这些发现为制定基于胎次的激素处理策略提供了依据,从而有助于提高肉牛的繁殖效率。

英文摘要:

      Low reproductive efficiency in beef cattle remains a critical factor limiting the industry"s development. Although the use of exogenous reproductive hormones can regulate the estrous cycle and improve fertility, differences in the hormonal response between cows of different parities during estrous regulation and superovulation have been observed. In this study, we employed the ELISA method to measure hormone levels, monitoring the concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and progesterone (P4) in QinChuan cows throughout their estrous cycles. The results showed that the FSH concentration in young cows on day 15 was significantly higher than that in multiparous cows (P<0.05). Similarly, the E2 concentration was significantly higher in young cows on days 0 and 20 (P<0.05), while the P4 concentration was significantly elevated in young cows on days 5, 10, 15, and 20 (P<0.05). Furthermore, LH concentration was consistently higher in young cows throughout the entire estrous cycle (P<0.05). These findings provide a basis for developing parity-based hormone treatment strategies, thereby improving reproductive efficiency in beef cattle.