雅砻江鲈鲤的人工繁殖、胚胎及卵黄囊仔鱼发育

采用不同配伍的外源激素对培育成熟的野生鲈鲤进行人工催产,并对其胚胎和1-10日龄卵黄囊仔鱼的发育进程进行详细的观察和描述。注射促黄体素释放激素类似物A2、地欧酮和绒毛膜促性腺激素的鲈鲤亲鱼组的催产效果明显好于注射鲤鱼脑垂体和促黄体素释放激素类似物A2的亲鱼组,效应时间为58h,平均受精率和平均孵化率分别为87.33%和90.75%。在水温(16±2)℃条件下,鲈鲤胚胎发育历时117.83h,所需积温为1855.33℃·h,出膜10d后仔鱼开始平游。鲈鲤胚胎发育分为受精卵、卵裂期、囊胚期、原肠胚期、神经胚期、器官形成期和出膜期7个阶段,共26个时期。分析发现,在人工催产配伍激素中添加适量的绒毛膜促性腺激素,有助于鲈鲤亲本顺利排卵;鲈鲤卵黄囊仔鱼在孵化出膜后的前5d处于内营养阶段,第6d起转入混合营养阶段,为仔鱼培育的第一危险时期。

Artificial Propagation,and Embryonic and Yolk-sac Larval Development in Percocypris pingi in Yalong River

The wild Percocypris pingi was reared to spawn induced by injection of hormone to obtain fer‐tilized eggs in this study .The results showed that females injected with LHRH‐A2 +DOM+ HCG ovula‐ted more fluently ,with the response time of 58 h ,mean fertilization rate of 87 .33% and mean hatching rate of 90 .75% .Furthermore ,the embryonic and yolk‐sac larval development were described in detail . Under the water temperature of (16 ± 2) ℃ ,fertilized eggs were hatched in 117 .83 hours with the accumu‐lative temperature of 1855 .33 ℃ · h .The embryonic development was divided into 7 stages including 26 subphases :fertilized egg ,cleavage stage ,blastula stage ,gastrula stage ,neurula stage ,organogenesis stage and hatching stage .The yolk‐sac larva grew rapidly and endogenously by in the first five days after hatching ,turned into the stage of mixed nutrition ,a critical stage ,since the sixth day ,and started to swim horizontally ten days later .