松江鲈胚胎及胚后发育研究

Embryonic and Postembryonic Development of Roughskin Sculpin Trachidermus fasciatus

采用人工繁育的松江鲈子一代为亲本,人工授精,在水温6℃、盐度32的条件下人工脱黏孵化,观察了胚胎发育。结果显示:松江鲈受精卵经过7 h进入卵裂期,经过2 d发育至囊胚期,5 d进入原肠期,经过9 d发育至眼囊期,17 d出现围心腔,22 d时肌节形成,29 d时体色素开始沉积,30~35 d孵出。在水温11.37℃~16.88℃、盐度32的条件下进行仔稚鱼培育。初孵仔鱼平均全长6.98 mm,出膜后4 d卵黄囊完全吸收,出膜后28 d背鳍、腹鳍、胸鳍和尾鳍发育完全,体表黑色素沉积增加,进入稚鱼期,出膜后55 d身体不透明,进入幼鱼期。结果显示,由于水温等环境因素的原因,胚胎发育与胚后发育各个阶段所需的时间与前人的研究结果存在一定差异。

The embryo development was observed in artificially fertilized and debonding eggs of first generation of artificially bred roughskin sculpin Trachidermus fasciatus,and incubated under the conditions of water temperature of 6℃and a salinity of 32.It was found that the cleavage was observed 7 hours post fertilization(HPF),blastula in 2 days post fertilization(DPF),gastrula stage 5 DPF,eye sac stage 9 DPF,pericardial cavity stage 17 DPF,myomere stage 22 DPF,pigmentation state 29,and hating 30~35 DPF.The larvae and juveniles were cultured under the condition of water temperature 11.37℃~16.88℃and a salinity of 32.The newly hatched larvae had laverage total body length of 6.98 mm,with exhausted yolk sac in 4 days post hatching(DPH)and dorsal fin,ventral fin,pectoral fin and caudal fin in 28 DPH at natural water temperature,with increase in the melanin deposition on the body surface.It was when the larvae became postlarvae.The body transparency basically disappeared 55 DPH when the roughskin sculpin turned into juvenile stage.The results showed that the time required for each stage of embryonic development and post-embryonic development was different from that of previous studies,this may be due to different water temperature during embryogenesis and post-embryonic development of roughskin sculpin.