条石鲷胚胎及仔稚鱼的发育

Study on the embryo & larva fish development of Oplegnathus fasciatus

通过对条石鲷胚胎发育和仔鱼发育形态的观察,确定了条石鲷早期发育的进程.条石鲷的受精卵为圆球形、透明、浮性,卵径为0.90～0.95 mm, 油球1个,卵裂为盘状卵裂.在水温23～24℃,盐度26～28的条件下,受精后7 h 10 min,胚胎发育至原肠期;受精后12 h,眼囊形成;受精后20 h 30 min,心跳开始搏动;受精后26 h 30 min,仔鱼孵出.初孵仔鱼全长1.78～2.03 mm,至5日龄全长3.25～3.30 mm时,卵黄囊完全消失;至8～15日龄,全长3.50～4.97 mm时,鳔形成;至18～20日龄,全长7.10～7.31 mm时,尾鳍鳍条发育完整.

The morphological features of embryonic and larval developmental in Oplegnathusfasciatus were described to determine the developmental process. The fertilized eggs with a lipid drop were oval pelagic and transparent. Egg cleavage acted as in discoidal segmentation. Under water temperature 23 - 24℃, salinity 26 - 28, the embryo developed to the stage of gastrula, eye sac, heart beat at 7 h 10 min, 12 h, 20 h 30 min after fertilization respectively. Through total 26 h 30 min embryo development, the larvae finally hatched with 1.78 - 2.03 mm whole length. The yolk sac of larvae would disappear after 5 days post hatching. To whole length 3.50 - 4.97 ram, air bladder of larvae formed about 8 - 15 days post hatching. Then the soft rays of caudal fin developed finally at 18 - 20 days post hatching with 7.10- 7.31 mm whole length.