池塘养殖金钱鱼的胚胎发育及胚后发育观察

Embryonic and postembryonic development of Scatophagus argus in pond-culture

为建立金钱鱼（Scatophagus argus）人工繁殖技术，采用人工养殖的金钱鱼经人工催产获得受精卵，对胚胎及初孵仔鱼发育在双目显微镜下进行了连续观察和研究。结果表明：水温（24±0.2）℃，盐度28条件下，金钱鱼正常发育特征为受精卵经28．5h孵化出膜。受精卵呈规则圆形、具光泽、卵膜薄且无色透明，直径（681．5±11．2）μm；受精后4h进入囊胚期；6．5h进入原肠期；12．5h进入胚体形成期；13．5h进入器官形成期，器官形成依次为视囊期、尾泡出现期、肌节期、脑泡期、耳囊期、尾芽期、晶体期、尾鳍期和肌肉效应期；28．5h开始出膜；31．5h达出膜高峰。初孵仔鱼头朝下侧卧，运动不活跃，全长1615．46-1650．35岬，初孵仔鱼6．5h直肠出现，肛门未通；32h肛门通，51h开口。金钱鱼早期发育研究为金钱鱼生产性育苗工艺和管理技术的建立提供科学依据。

In order to establish an artificial breeding technology for Scatophagus Argus, fertilized eggs were obtained from pond-raised Scatophagus argus using the hormonal injection method. The development of embryoes and newly hatched larvae were observed under a microscope. The result showed that the larvae hatched out at about 28.5 h after fertilization in condition of water temperature （24±0.2）℃ and salinity 28. The fertilized egg was round, glossy, and colorless, with a thin egg envelope, and it was （681.5±11.2） μm in diameter. Blastula stage, gastrula stage, and embryo body stage, organ formation stage appeared at 4 h, 6.5 h, and 12.5 h after fertilization, respectively. The organ formation stage appeared at 13.5 h after fertilization, which included optic capsule stage, tail vesicle stage, myotome formation stage, brain vesicle stage, otic capsule stage, tail bud stage, lens formation stage, caudal fin stage, and muscular contraction in chronological order. The hatching stage appeared at 28.5 h and peaked at 31.5 h after fertilization. The newly hatched larvae were in a state of head over heels, body lied on the side, not active in movement, 1615.46 -1650.35 μm in the total length, and its rectum did not appear until 6.5 h after hatching with close anus. The anus of the atched larvae was open at 32 h after hatching and its mouth opened at 51 h after hatching. The study of embryo and larval development in Scatophagus argus is to provide the scientific basis for reproductive technology and management of artificial breeding.