新疆扁吻鱼的胚胎发育和仔鱼发育的初步观察

Preliminary Observation on Embryonic and Fry Upgrowth of Aspiorhynchus laticeps(Day)

2006年4月首次利用人工驯化成熟的扁吻鱼亲鱼进行人工繁殖试验，并获得成功。试验期间观察了扁吻鱼的胚胎发育和仔鱼发育的形态特征及发育特点。该鱼的成熟卵呈圆球形，青灰色，沉性和具微黏性。卵径1．5—1．7mm，吸水膨胀后卵径达2．6—2．8mm。在水温幅度18℃-21℃时，受精卵1h40min形成胚盘,2h进入卵裂期，12h进入囊胚期，21h50min为原肠中期，30h进入神经胚期，44h17min肌肉开始收缩，64h后心跳开始，多数受精卵经95h后出膜。出膜仔鱼长7—8mm。第6d仔鱼全长约10mm，卵黄囊基本被吸收，鳔充气，鱼苗开始平游，并开口摄食。在水温幅度13℃-19℃时，受精卵经120-130h后出膜。

In this study, an experiment of artificially breedingAspiorhynchus laticeps （Day） in the Aksu River, Xinjiang, was successfully carried out in April 2006, and the morphological characteristics of the eggs and the embryonic and fry growth ofA. laticeps （Day） were lucubrated. The ripe eggs are spherosome-shaped, caesious and slightly adhesive, their diameter varies in a range of 1.5 - 1.7 mm, and their maximal diameter varies in a range of 2.6 - 2.8 mm after they are adsorbed with water to expand. In water with temperature of 18℃ - 21℃, the oosperms become as blastoderms after 1 hour and 40 minutes, the cleavage occurs 2 hours late, blastula occurs 12 hours late, gastrular cleavage occurs 21 hours and 50 minutes late, neurulation occurs 30 hours late, muscle contraction occurs after 44 hours and 17 minutes, heartthrob starts after 64 hours, and most oosperms hatch out of the membranous walls after 95 hours. The body length of the newly-hatched fries is 7 - 8 mm and grow to 10 mm on sixth day, the yolk sac is almost absorbed, the swim bladders begin to charge, and the fries begin to swim and eat. In water with temperature of 13℃ - 19℃, the oosperms can hatch out of the membranous walls after 120 - 130 hours.