大泷六线鱼仔鱼摄食及生长的研究↑（*）

本文以大泷六线鱼(Hexagrammosotakii)人工孵化所得的卵黄囊期仔鱼为材料,对仔鱼早期阶段的摄食及生长情况作了实验研究。结果表明:在13.5～14℃条件下,大泷六线鱼仔鱼6日龄开始摄食,约8日龄卵黄囊耗尽,10日龄饥饿仔鱼进入PNR期,混合营养期为2d;饥饿仔鱼的开口率(初次摄食率)开始较低,此后上升,到卵黄囊耗尽时达高峰(63%),以后又下降。仔鱼前期的生长率平均为0.254mm/d,饥饿仔鱼生长几乎停止,同期喂食仔鱼的生长率亦下降为0.102mm/d;摄食仔鱼在孵化后20d内的全长(L)和日龄(d)的相关式为L=0.085d 7.04。仔鱼存在昼夜摄食节律,在1昼夜中有2个摄食高峰,分别出现在14:00和20:00。

Studies on feeding and growth of fat greenling during early development

The larval fat greenling (Hexagrammos otakii)begins to feed at 6 d of age. At 10 d of age, the larvae, who didn't feed from outside, enter the period of PNR. The yolk is exhausted at day 8. The initial feeding rate is lower, then slowly reachs the peak when the yolk is exhausted. After that, it decreases. The highest initial feeding rate is 63%.The growth rate of larvae before the period of feeding is 0.254 mm/d. When they enter feeding period the unfed larvae almost stop growing. At the same time the feeding larvae's growth rate decreases to 0.102 mm/d. The relations of the feeding larvae between total length (L) and days of age within 20 d after hatching is L(mm)=0.085 d 7.04. The larvae have feeding rhythms day and night,and have two feeding peaks: one is at 14:00, and the other at 20:00.