池养鲻的卵巢发育和卵子发生过程

通过卵巢切片的组织学分析揭示，幼鲻在土池养殖3个月后可见线状卵巢，大约5个月后卵原细胞进入第一次成熟分裂前期的双线期转变为早期初级卵母细胞。接着卵母细胞生发泡(核)和胞质体积增加，核质比从3．5：1减少至2：1。此后卵巢中卵母细胞停滞发育持续至养殖的第3年。在第3年卵巢切片看出卵母细胞进入脂肪泡时相，在第3年秋季进入卵黄发生时相。但在人工养殖条件下卵母细胞仅能发育到卵黄发生后期，即卵母细胞胞质充满卵黄颗粒，生发泡居中而不移位。这些结果对于用人工养殖鲻为亲鱼开展人工繁殖提供重要的科学依据。并讨论了卵子发生6个时相的生物学特点及其重要的细胞器在卵黄发生中可能的生理作用。

The process of the ovary development and oogenesis in the cultured-pond Mugil cephalus

The biological character of ovary development and oogenesis in the artificial cultured grey mullet of outdoor pond was reported firstly. The analysis of ovary histological sections revealed that an ovary of thin line was seen in grey mullet after being cultured for three months, then, the oogonia of diplotene stage of the first meiotic prophase in ovary transformed into primary oocyte after being cultured for about five months. During this stage the germinal vesicle (nucleus) and cytoplasm increased in volume, but the nucleo-cytoplasmic ratio decreased from 3.5 : 1 to 2 : 1. The development of early oocytes in ovary stagnated until the third year of culture. At that time, the oocytes of adipose vesicle phase could be seen in the sections of ovary. The oocytes of vitellogenic phase occurred in the autumn of the third year . We have observed that under the artificial cultured condition of outdoor pond the ovary of grey mullet could not complete maturation and the oocytes only developed into the late stage of vitellogenesis, i. e, the cytoplasm of oocyte was full of yolk granules and germinal vesicle located at center without migration. These results will provide the important scientific basis for the artificial prepagation using cultured grey mullet. Finally, the biological character and physiological role of important cell organella in the oocytes of six phases in the process of oogenesis were discussed in the paper.