摘要
湖南地区鳖的性成熟年龄是四年。成熟雌鳖每年产卵3—5次(窝),一般每次产卵8—12个,最多可达20—26个,是典型的多次产卵类型。由8—10微米直径的卵原细胞,长足到17—20毫米的成熟卵子,其间可以分为卵原细胞期、初级卵泡期、生长卵泡期和成熟卵泡期。在生长卵泡期可以看到由卵表伸向放射膜内的微绒毛(microvilli),这种结构与卵黄形成所需的物质转运有关。曲细精管中精子的正常形成和存活,不受季节变化的影响。进入雌鳖输卵管中的精子经过冬季到来年的生殖季节仍保持受精能力。
We discovered the year rings in the scapular bone of Trionyx sinensis and by which the age for sexual maturity of the turtle has been determined to be four years. The mature females spawn 3—5 times per year, each time it generally lays 8—12 eggs and at most 20—26 eggs. Hence the female turtle belongs to the type of spawning several times a year. A fully mature egg, which is differentiated from oogonium 8—10 micron in dimeter, reaches 17—20 mm in diameter. The entire course of oogenesis, from oogonium to mature egg, can be divided into four stages, i. e. oogonium, primary follicles, growing follicles and mature follicles.We observed that the microvilli on the sur face of oocyte insert into the radial membrane during the growing follicular stage; this structure may be related to the transportation of substances which are necessary for the formation of volk.No seasonal changes of the normal formation and existence of spermatozoa have been found in the seminiferous tubules. Our research also discovered that the spermatozoa which enter female's oviduct in the summer or autumn could retain their capacity of fertilization in the reproductive season of the next year.