倒刺鲃仔稚鱼发育的观察

Observation on larval and juvenile development of Spinibarbus denticulatus

以人工繁殖的倒刺鲃仔鱼为材料,观察了仔鱼发育过程,对各个发育期的形态特征进行了描述。结果表明:倒刺鲃仔鱼发育可分为卵黄囊仔鱼、晚期仔鱼、稚鱼期;初孵仔鱼平均全长(6.16±0.29)mm;水温(25±0.5)℃时,开口时间为2日龄,具有摄食能力的时间为5.15日龄;卵黄囊消失时间为7.79日龄,混合营养期为2.64 d;发育到9日龄时,尾鳍鳍条开始出现;到18.79日龄时,仔鱼各鳍鳍条全部形成,进入稚鱼期;发育到22日龄时,个别鱼体出现透明鳞片;仔鱼全长与日龄成直线相关,其回归方程为:LT=0.4801D+6.9620(R2=0.9870)。

The present paper reports the results of observation on larval development of Spinibarbus denticulatus. Larvae obtained by artificial fertilization and incubation were used in this study. The results showed：the larval development of Spinibarbus denticulatus was divided into yolk-sac larva, late stage larva, juvenile stage. The mean of total length of newly hatched larvae was （6. 16 ± 0. 29 ） ram. When water temperature was （25 ± 0.5 ） ℃, larvae had an opened mouth 2 days after hatching, and the larvae began to feed at 5.15 days old. Yolk was exhausted at 7.79 days old, and its mixtrophic stage continued for 2.64d. Caudal fin rays appeared on 9 days old. All of spines and soft rays completed and larvae entered juvenile stage at 18.79 days old. 22 days after hatching, some larvae had scales and developed into young fish. The linear relation model between total length and age is Lr =0. 4801D ＋6. 9620（R^2 =0. 9870）.