Abstract: Two feeding experiments were conducted to elucidate the effects of dietary lipid and emulsion levels on growth and approximate composition in juvenile sea cucumber （Apostichopus japonicus ）. In experiment 1, juvenile sea cucumber weighing 2.71 g in body weight was stocked into 24 plastic tanks of each 45 cm × 31cm × 30 cm and fed the 19.8% crude protein diets containing 2.80%, 3.65%, 4.50%, 5.35%, 6.20% and 7.05% of fat （deep sea fish oil） at 11.5 -21.5 ℃ for 60 days. The sea cucumber fed the diet containing 6.20% of oil was found to have the maximal special growth rate （SGR）, apparent digestible fatty levels and polyunsaturated fatty acid levels （ % ） in body. A second order polynomial regression model between SGR （Y） and dietary fatty levels （X） （Y= -0. 029X2 ＋0. 341X ＋ 0. 071 ） suggested that the optimal dietary fat level was recommended to vary from 5.35% to 7.05%, and the fatty level of 5.88% which corresponded to the maximum growth. In experiment 2, soybean phospholipd as emulsion was added to the diets at a rate of 0, 5%, 10% and 15% of soybean oil to prevent juvenile sea cucumber from envisceration at water temperature of 11.5 - 14.5 ℃ for 45 days. The sea cucumber fed the diet containing 10% of emulsion showed significant higher special growth rate than that in other groups and had significantly higher apparent digestibility of fatty levels than those in the other groups （P 〈 0. 05）. Soybean phospholipd was found to act as good emulsion to prevent sea cucumber from intestines atrophy.
2009, Vol. 24 
