不同月龄荷斯坦奶牛对超排效果的影响

The Effect of Different Month-age Holstein Diary Cattle on Superovulation

用青年牛进行超排可以加快遗传进展,缩短世代间隔。试验对不同月龄的青年奶牛和成年奶牛的超排效果进行了比较,分别为7～9.9月龄、10～12.9月龄、13～15月龄和成年奶牛。183头奶牛中有170头奶牛超排有反应,且不同月龄的奶牛在超排成功率上没有显著差异,但随着超排奶牛月龄的增加,超排成功率有升高的趋势。170头奶牛中有1468枚胚胎冲出,其中920枚胚胎可用(62.7%)。7～9.9月龄的奶牛的平均获胚数为5.4枚,可用胚为2.8枚,显著低于其它组别(P<0.05)。大于10月龄的青年奶牛各组间的超排效果没有显著差别(P>0.05),平均获胚数为8.9枚,平均可用胚为5.6枚。不同月龄对未受精卵率的影响不大,但是小于10月龄的青年奶牛的变性胚率要显著高于其它组别的奶牛(P<0.05)。这些结果表明,大于10月龄以上的奶牛可以成功地进行超排,但是小于10月龄的奶牛不能应用于胚胎的商业化生产中。

Utilizing heifers for superovulation can quicken genetic evolution and shorten generational interval. In this paper, the superovulatary effects of different month-old heifers and cows were compared, 7～7.9,10～12.9,13 ～ 15month-old separately. During 183 donors, 170 had the superovulatary response, there were no differences during different month-old donors at the rate of superovulatary, but there was a increasing trend go ing with rising age. There were 1 468 embryos flushed for the 170 donors, 920 were useable （62.7%） . The average embryo number and average useable embryo number for the 7～9. 9 month-old group were 5.4 and 2. 8, less than other group＇ s markedly （P〈0. 05）. There were no differences between groups of more than 10 month-old donors at the average embryo number and average useable embryo number, the average embryo number and average useable embryo for donors of more than 10 month-old were 8.9 and 5.6 seperatly. There was no influence for non-fertilized rate during different month-old do- nors, but the denatured embryo rate in the 7～9. 9 group was more than other group＇s markedly （P〈0.05）. These results showed that, heifers that were more than 10 month old could be superovulated successfully, but heifers that were less than 10 month old could not be utilizing for the embryo production.