青年奶牛活体取卵技术的研究

本文利用B超活体取卵技术(ovumpickup,OPU)对青年荷斯坦奶牛活体取卵,探讨影响活体取卵的因素及对青年奶牛发情周期的影响。4头青年荷斯坦奶牛在连续观察两个发情周期后,进行连续的一周一次OPU操作,持续16周,然后观察OPU后的发情周期特征及卵巢状况。结果显示:在数量上,个体间穿刺卵泡的总数和回收卵母细胞的总数不完全一致,但卵泡直径的百分比构成个体之间无显著差异(P>0.05),回收率相似;在质量上,各级卵母细胞的构成在各个体间没有显著差异(P>0.05);OPU期间奶牛出现情期延长的趋势,且发情表现减弱,但停止OPU后发情基本正常。研究表明:利用活体取卵技术对青年荷斯坦奶牛进行每周一次的长期连续取卵,在一定的条件下,能够达到较为稳定的回收率和获得一定数量和质量的卵母细胞,但会导致奶牛发情周期的改变,而在停止OPU后能较快恢复。

A Study of Ovum Pick up on Dairy Heifers

To discuss the effect and impact of ovum pick up (OPU) on Holstein dairy heifers, OPU was carried out under the B-type ultrasound scan guidance. After characterization of two normal estrous cycles, four heifers were subjected to consecutive 16 weeks of once-weekly OPU. Afterwards, the status of ovaries and estrous cycle characteristics were observed. On quantity, the total number of follicles and recovered oocytes were different between individual heifers, but there was no significant difference on percents of different sizes of punctured follicles and recovery rates. On quality, the percents of different categories of oocytes were similar. During OPU period, the heifers showed a longer cycle length and weak signs of estrus, but normal estrous cycle nearly came back soon after OPU. The research demonstrates that certain quantity and quality oocytes and stable recovery rate can be obtained from long-term once-weekly OPU on Holstein dairy heifers, but the characteristics of estrous cycle will be changed and become nearly normal soon after OPU.