斜带石斑鱼种苗转饵模式研究

Weaning of Orange-spotted Grouper(Epinephelus coioides)Larvae by Means of Different Feeding Regimes

对36日龄平均体质量(0.21±0.01)g的斜带石斑鱼种苗的转饵模式进行研究。设计5种转饵模式:转饵1组前10d投喂生物饵料,然后转投配合饲料;转饵2、转饵3和转饵4组前10d进行联合投喂(转饵2:25%配合饲料+75%生物饵料;转饵3:50%配合饲料+50%生物饵料;转饵4:75%配合饲料+25%生物饵料),然后转投配合饲料;转饵5组直接投喂配合饲料;转饵试验至种苗60日龄结束。试验结果表明,由于鱼体长度变异系数显著高于其他各组(P<0.05),转饵4组试验鱼死亡率最高,而其他各组之间差异不显著(P>0.05);试验结束时,转饵1组试验鱼体质量和质量增加率最低,显著低于其他各组(P<0.05),而转饵2组又显著低于转饵4和转饵5组(P<0.05);转饵1组种苗36—45日龄的特定生长率显著低于其他各组(P<0.05),而46—60日龄的特定生长率显著高于其他各组(P<0.05)。转饵试验结束后,各组种苗全鱼水分和粗蛋白含量差异不显著(P>0.05),转饵5组种苗全鱼粗脂肪含量显著低于其他各组(P<0.05)。综合比较各项指标,转饵3的模式种苗质量增加率较高而死亡率较低,是本研究中效果较好的转饵模式。

The suitable feeding regime was studied for weaning of orange-spotted grouper（Epinephelus coioides）larvae 36 days after hatch（DAH）with average body weight of（0.21±0.01）g.The larvae were fed by five feeding regimes as following：in regime R1,the larvae fed live food（LP）in the first ten days,and then weaned onto inert diet（ID）;in regimes R2,R3 and R4,the larvae fed the mixed diet in the first ten days（R2：25%ID ＋75% LP;R3：50%ID ＋50% LP;R4：75%ID ＋25% LP）,and then weaned onto ID;in regime R5,the larvae fed ID in 36DAH（at the end of the weaning experiment）.The results showed that there was the maximal mortality（DR）in the larvae in regime R4 due to significantly higher coefficient of variance（CV）of body length（P〈0.05）,significantly higher than those in other regimes（P〈0.05）,and there were no significant differences in CV and DR among other regimes（P〉0.05）.The minimal final body weight and weight gain rate（WGR）were observed in the larvae in regime R1 at the end of the experiment,significantly lower than in other regimes（P〈0.05）,and significantly lower in regime R2 than regimes R4 and R5（P〈0.05）.The larvae in regime R1 had significantly lower specific growth rate than the larvae in other regimes did during 36—45DAH（P〈0.05）,and significantly higher than in other regimes during 46—60DAH（P〈0.05）.After the experiment,there were no significant differences in moisture and crude protein content in the larvae among all feeding regimes（P〉0.05）.However,the larvae in regime R5 had significantly lower crude lipid content than the larvae in other regimes did（P〈0.05）.It is concluded that feeding regime R3 is the optimal feeding regime for the larvae which showed higher WGR and lower DR.