The process of gonadal development and differentiation of large yellow croaker Larimichthys crocea was investigated with histological methods. The sampled fries were hatched on Sept. 22 , 2009 at 26 ℃. The temperature for nursery and culture were 22.0 - 25.8 ℃ and 11.5 - 25.6 ℃, respectively. At the age of 20 days post hatch (dph ), when the fries gained 17.6 - 19.2 mm in body length (BL), a pair of primordial gonads were present in the abdominal cavity. Ovarian differentiation occurred at 55 dph (BL 27.5 -37.0 mm), and was characterized by the presence of clusters of oogonia. The formation of ovarian cavity and meiosis of germ cells began simultaneously at the age of 60dph (BL 28.0 - 37.2 mm). The presence of primary oocytes occurred at the age of 120 dph (BL 39.2 - 51.0 mm). The differentiation of testis began at the age of 95 dph (BL 38.0 - 48.0 mm) and was characterized by the presence of efferent duct and the scattering of somatic cells throughout the gonad. Cyst of spermatocytes could be seen at 215 dph (BL 44.0 - 59.2 mm) and testis lobules started to form at 230 dph (BL 56.2 -72.8 mm). These results suggested that large yellow croaker is a differentiated gonochorist, and differentiation of the ovary occurs earlier than that of testis.%利用组织学方法研究了大黄鱼的性腺分化和发育规律.大黄鱼受精卵于2009年9月22日开始孵化,孵化水温26℃,育苗水温22.0～25.8℃,养殖水温11.5 ～ 25.6℃.20日龄稚鱼(体长17.6～ 19.2 mm)腹腔中一对原始性腺已经形成.55日龄幼鱼(体长27.5 ～ 37.0 mm)半数个体性腺中形成成簇发育的卵原细胞群,标志着卵巢解剖学分化开始.减数分裂和卵巢腔的形成同时开始于60日龄(体长28.0 ～ 37.2 mm).120日龄幼鱼(体长39.2～51.0 mm)性腺中,初级卵母细胞出现,标志着卵巢细胞学分化的开始.精巢分化开始于第95日龄(体长38.0～48.0 mm),其解剖学标志为生精导管的形成及体细胞在性腺中的散布方式.145 ～ 195日龄,由于水温过低,鱼苗停止生长,期间性腺发育水平没有明显变化.215日龄幼鱼(体长44.0～59.2 mm)性腺中精母细胞的出现标志着精巢细胞学分化的开始.精小叶于230日龄(体长56.2～72.8 mm)形成.由此可见,大黄鱼雌性性腺发育早于雄性性腺,且大黄鱼性腺分化类型属于分化型雌雄异体型.
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