补饲对母牦牛同期发情处理的效果分析

Effect analysis of supplementary feeding on the treatment of estrus synchronization test in female yaks

为了对不同繁殖体况的母牦牛采取不同程度的补饲方案,研究补饲对母牦牛同期发情处理后发情和受胎的影响,从而探讨环湖地区牦牛繁殖率低下的形成机理及解决方案。试验选用青海省环湖地区3～10岁营养体况相近的受体母牦牛352头,按试验要求随机将青年牛、经产牛分为3组,分别补饲0,0.5,1.0 kg饲料,补饲时间为3个月,补饲结束后实施同期发情试验和定时授精,授精后40～60 d采用直肠检查法检查受胎情况。结果表明:补饲前与补饲后相比青年牛、经产牛营养状况差异显著(P<0.05),不同卵巢机能状态对母牦牛的发情率和受胎率的影响差异极显著(P<0.01),补饲Ⅱ组和补饲Ⅰ组青年牛、经产牛的发情率和受胎率与对照组相比差异极显著(P<0.01),补饲Ⅱ组与补饲Ⅰ组青年牛、经产牛同期发情处理后的发情率和受胎率与对照组差异显著(P<0.05)。说明母牦牛体内营养储备状况是制约牦牛繁殖率的关键因素,在传统的放牧条件下通过适度补饲能够改善母牦牛的繁殖体况和卵巢机能状态,可明显提高母牦牛的发情率和受胎率。

To investigate the effect of different levels of supplementary feeding on the estrus and conception for female yaks after the treatment of estrus synchronization, exploring the mechanism of low reproductive rate of female yaks around the Qinghai Lake. 352 three to ten - year - old female yaks around the Qinghai Ia.ke areas were divided into three groups with different feeding programs, including 0 kg, 0.5 kg and 1.0 kg of concentrated feed in the supplementary feeding. After 3 months supplementation, the implementation of synchronization of oestrus and timed insemination experiment was conducted. The pregnancy was checked by rectal examination at 40 - 60 days after insemination. The results showed that the difference between before and after supplementary feeding was extremely significant （ P 〈 0.05 ） in the nutritional status of the young and muhiparous yaks, and the difference was extremely significant （ P 〈 0. 01 ） in the effects of estrus and pregnancy for the female yaks with various functional states of ovaries. For the comparison of the estrus and pregnancy effects for the young and multiparous yaks, the differ- ence was extremely significant （P 〈 0. 01 ） both of the supplementary group I and I1 compared to the control, but there was no significant difference （ P 〈 0. 05 ） between the supplementary group I and ii. The results indicate that the body＇ s nutritional reserve of female yak is a key factor to restrict the reproduction rate of yak. Appropriate supplementary feeding can improve the body＇ s reproductive condition and ovarian function of female yaks under traditional grazing conditions, and can significantly increase the estrus and conception rates.