松江鲈幼鱼性腺分化的组织学观察OA北大核心CSTPCD

To elucidate the processes of gonadal differentiation and development in Trachidermus fasciatus,larvae at 10-120 days post-hatching(dph)were examined using conventional paraffin sections and hematoxylin-eosin tissue staining.The results revealed several key milestones:primordial gonadal formation at 20 dph,appearance of the embryonic ovarian cavity at 40 dph,initiation of ovarian cytological differentiation marked by primary oocytes at 45 dph,entry into stage Ⅱ at 60 dph,and appearance of fissure seminiferous tubules at 65 dph indicating the onset of anatomical differentiation of the testis(stage Ⅰ).Furthermore,at 70 dph,the formation of a spermatogonium ves-icle signaled the cytological differentiation of spermatogonia.By 90 dph,the presence of stage Ⅱ spermatocytes,forming primary spermatocytes arranged in bundles,marked a significant stage in testicular development.T.fasci-atus exhibited heteromorphic differentiation into males and females.The oocyte development was partially syn-chronous,and the ability of lipid accumulation is relatively strong.The differentiation time of the testis was later than that of the ovaries,and the differentiation direction of the gonads was affected by the number of germ cells.T.fasciatus displayed distinct reproductive characteristics,providing valuable insights into its gonadal development and differentiation.These results clarified the gonadal differentiation process and key time nodes,provided im-portant foundational data for studying the sex determination mechanism,and also contributed theoretical reference for the artificial breeding and sex control induction sensitive periods in T.fasciatus.