Investigation of oocyte maturation and fertilizati in high-producing and sub-fertile dairy cows

为探讨现代高产奶牛低生育力的原因，对奶牛卵母细胞的成熟和受精特性进行了研究。结果显示了LH峰后排卵的时间和体内成熟的排卵前卵母细胞的超微结构。测定了精子运输至输卵管贮库所需时间和排卵卵母细胞的功能寿命。通过使用体外成熟卵母细胞，我们确定了发育能力获得的特征。此外，我们开发了一种新的治疗重复繁殖奶牛通过使用精浆蛋白，和一个新的体外卵母细胞生长培养系统，以检查应力对卵母细胞的生长和成熟的影响。本文还指出通过监测阴道温度变化预测排卵时间和异常排卵的可能性

To elucidate the causes of low fertility in modern high producing dairy cows, we investigated the characteristics of oocyte maturation and fertilization. As the results, the time of ovulation after LH surge and the ultrastructure of in vivo matured preovulatory oocytes were revealed. The time required for the sperm transport to the oviduct reservoir and functional life span of ovulated oocytes were estimated. By using in vitro mature oocytes, we defined the characters of acquisition of developmental capacity. Moreover, we developed a novel treatment of repeat breeding cows by using seminal plasma proteins, and a new in-vitro oocyte growth culture system to examine the effects of stresses on oocyte growth and maturation. The possibility of prediction of the time of ovulation and abnormal ovulation by monitoring vaginal temperature changes was also indicated