不同脂肪源对虹鳟(Oncorhynchus mykiss)生长和能量收支的影响

Effects of Four Dietary Lipids on the Performance of Growth and Energy Budget of Rainbow Trout, Oncorhynchus mykiss

本文探讨了三种植物油全部替代饲料中鱼油对虹鳟生长性能与各组分能量收支分配的影响。实验设置以鱼油为对照组,三个实验组脂肪源分别为大豆油、棕榈油、菜籽油,各组脂肪水平为20%。在16℃下饲养52d,每天饱食投喂两次。实验结果表明:(1)三种植物油替代鱼油对虹鳟生长性能无显著差异,但饲料中添加不同脂肪源对虹鳟各组分能量值以及能量分配影响显著;(2)添加大豆油组消化率93.19%,高于鱼油组92.07%、菜籽油组92.08%与棕榈油组92.03%,同时大豆油组粪便能分配率最低5.01%,但代谢能分配率最高41.04%(P<0.01);(3)菜籽油组排泄能分配最低为29.09%,表现出最佳能量分配策略。实验结果表明,虹鳟饲料中脂肪以添加菜籽油的能量分配策略最佳,棕榈油和鱼油效果相似。

The aim of the present study was to investigate the effects of total replacement of dietary fish oil by alternative lipid sources(soybean, rapeseed, palm) on the growth performance and energy budget of rainbow trout(Oncorhynchus mykiss). Three experimental diets were formulated to contain 20% of lipid the fourth was prepared with pure fish oil as control. The diets were fed to apparent satiation twice a day for 52 days at 16℃. The results showed that there was no significant difference in the performance of growth among diets. The energy budget of the rainbow trout, however, was different significantly among diets. Fish feeding diet containing soybean oil showed a higher apparent digestibility ratio(93.19%) than those feeding fish oil(92.57%), rapeseed oil(92.08%) and palm oil(92.03%) and the metabolism energy in food energy appeared the highest rate(41.04%) and the lowest fecal energy distribution rate(5.01%). The distribution of excretion energy of rapeseed oil was the lowest, showing the best energy allocation strategy. These results suggested that rapeseed oil is optimal dietary lipid in rainbow trout feed containing four lipid sources. Palm oil and fish oil showed the same effect on the energy allocation strategy.