Especially for rat, its long tail of sperm makes its sperm cryopreservation very hard.Accordingly, ICSI of rat is not done better than mouse.

• 尤其是大鼠，因为其较长的精子尾巴，使得它的精子冷冻保存相当困难，并且大鼠的卵胞浆内精子注射(ICSI)技术也没有小鼠那样成熟。