中华鳖精巢发育的组织学观察

[目的]研究中华鳖精巢的形成、分化和发育。[方法]以200枚中华鳖受精鳖卵为试验材料，研究1～4龄鳖的生殖腺指数以及精巢的形成、发育和组织学变化，观察其生精细胞及精子的显微结构。[结果]在（32±0．5）℃条件下孵化鳖卵，胚胎发育至第5天形成生殖嵴；第16天原始生殖细胞开始分化，至第24～26天性腺分化结束形成精巢或卵巢；成熟的精巢由生精小管组成，生精小管一侧为管壁上皮，另一侧为生发区；各个生精小管中生殖细胞发育基本同步，在生精小管内生殖细胞的成熟方式由近基膜处向管腔推进，依次是精原细胞、初级精母细胞、次级精母细胞、精子细胞和精子，最终进入输精小管。[结论]中华鳖精巢的发育可分4个时期，即精原细胞期、精母细胞期、精子细胞期和精子期。

Histological Observation on the Testis Development in Trionyx sinensis

[Objective] The aim was to study the formation, differentiation and development of testis in Trionyx sinensis. [Method] With 200 fertilized eggs of T. sinensis as tested materials, the gonad indices of 1-4 years old T. sinensis and the formation, development and histological change of their testes were studied and the microstructures of their spermatogenic cells and sperms were observed. [Result] The T. sinensis eggs were hatched at (32±0.5) ℃, the genital ridges formed on the 5th day of embryonic development period. The primordial germ cells started to differentiate on the 16th day. The differentiation of gonads finished and the testes or ovaries formed in the period from the 24th day to the 26th day. The mature testis was composed of seminiferous tubules, their one side was tube-wall epithelial and the other side was germinal region. The developments of germ cells in all the seminiferous tubules were basically synchronous. From near basal membrane to luminal, the maturation modes of germ cells in seminiferous tubules were spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids and sperms successively. Finally, the sperms entered into small sperm ducts. [Conclusion] The development of testis in T. sinensis could be divided into 4 stages: spermatogonium stage, spermatocyte stage, spermatid stage and sperm stage.