盐度对黄颡鱼幼鱼生长与饲料利用率的影响

目的]为推广黄颡鱼养殖技术提供参考。方法]用不同盐度水体养殖黄颡鱼幼鱼,研究其对水体盐度的适应性及盐度对其生长和饲料利用率的影响。结果]在盐度为11.5‰的水体中养殖96h后黄颡鱼无死亡现象,而盐度为14.4‰的水体中黄颡鱼全部死亡,且水体盐度越大,黄颡鱼死亡速度越快;水温为（25±1）℃时,黄颡鱼的安全盐度为3.83‰,48、96h的半数致死盐度分别为13.38‰、12.93‰;在盐度为2‰～7‰的水体中养殖85d后,黄颡鱼的成活率达94%～100%,鱼体日增重0.24～0.25g/尾,不同盐度水体中鱼体重增加幅度无显著差异;黄颡鱼的饵料系数在1.6～3.0,随水体盐度增加饵料系数呈下降趋势。结论]该研究明确了黄颡鱼幼鱼的耐盐性及其生长的适宜水体盐度范围。

Effects of Salinity on Growth and Feed Utilization Rate of Larva pelteobagrus

Objective] The study was to provide the reference for the extension of culture technology of Larva pelteobagrus. Method] The young L. pelteobagrus were cultured in water with different salinity. Their adaptability on water salinity and the effects of water salinity on their growth and feed utilization rate were studied. Result] After 96 h of culture, the L. pelteobagrus in water with salinity of 11.5‰ had no death phenomenon, while those in water with salinity of 14.4‰ all died. The higher the water salinity was, the faster the death rate of L. pelteobagrus was. When the water temperature was (25±1) ℃, the safety salinity for L. pelteobagrus was 3.83‰ and the IC50 after 48, 96 h of salinity was 13.38‰, 12.93‰ resp.. After 85 d of culture, the survival rate of L. pelteobagrus in water with salinity of 2‰-7‰ was 94%-100% with daily weight gain of 0.24-0.25 g/fish. The increment of body weight of L. pelteobagrus in different salinity water had no significant difference. The feed coefficient of L. pelteobagrus was 1.6-3.0 and it showed decreasing trend with the increase of water salinity. Conclusion] The study determined the salt-resistance of young L. pelteobagrus and the optimum salinity range of water for it.