“假黄牛”或“假牦牛”精母细胞减数分裂及精子发生的研究

The Meiosis and Spermatogeny of the Spermatocyte form “False Yellow Cattle ”or “False Yak”

黄牛与牦牛种间杂交的Ｆ３代杂种公牛，精母细胞减数分裂及精子发生的水平，与Ｆ１和Ｆ２代相比，呈现明显的渐进性改善。但个体间睾丸发育状况及减数分裂与精子发生水平仍有较大差异，且仍能观察到一些异常现象。Ｆ３代公牛虽能产生数量较多的精子，但大多仍是畸形或有缺损，这可能是其仍无生育力的主要原因。

The meiosis and spermatogeny of spermatocyte of F 3 bull bybridized between the yellow catlle and yak have an apparent improvement compared with F 1 and F 2.But there are certain differences among individuals testis development ,meiosis and spermatogeny and some abnormal phenomina .F 3 bull can produce a large amount of sperm ,but the majority of which are deformed or defected ,which are probably the main cause for their sterility .