南方鲇受精细胞学观察

Cytological Observation on Fertilization of Southern Catfish Silurus meridionalis

对17℃和24℃水温条件下受精的南方鲇Silurys meridionalis受精卵进行了细胞学观察。结果表明，南方鲇属于单精入卵、单精受精，在17℃的水温条件下，受精后约20s精子进入卵子细胞质，受精后20min左右卵子形成第2极体，并排出体外，受精后25min左右雌雄原核形成，40-45min雌雄原核开始接触并部分融合，50min雌雄原核完全融合形成合子核。24℃条件下除了雌雄原核的形成和融合的时间早一些外，其他受精细胞学程序与17℃基本一致。

The artificial fertilization processes of southern catfish Siluru~ meridionalis were observed cytologically under the water temperature of 17℃ and 24℃. The results showed that the fertilization of southern catfish was monospermy. Under the water temperature of 17℃, the sperm entered into the egg at about 20s after fertilization. The second polar body formed and was extruded at about 20min after fertilization. At around 25min after insemination, the sperm transformed into male pronucleus as well as the female pronucleus was formed at the same time. The male pronucleus and female pronucleus fused partly at 40 - 45 min and fused completely at around 50min after insemination. In the water temperature of 24℃, the cytological behaviors were almost the same as that observed under 17℃ , except that the time of these behaviors appeared earlier.