Rotifer Brachionus plicatilis was used as the test species. The diets with different lipid sources were as follows: ( 1 ) Baker' s yeast, Saccharomyces cerevisice (control); (2) algae, Nannochlorpsis oculata ( diet A);(3) fish oil(5%) + soybean lecithin (5%) + Baker's yeast(90%)(diet B); (4) fish oil (10%) + Baker's yeast(90 96 )(diet C). The results show that: (1) Considerable difference of fatty acid composition exists in the rotifers fed corresponding diets compared with control, and the highest level of n-3 HUFA fatty acids in the rotifers fed diet C is obtained due to high level of n-3HUFA content in diet. The conclusion is that the HUFA content of diet is a major factor in affecting HUFA levels in the rotifers. (2) The effect of dietary lipid on the fatty acid composition is not only based on dietary level of HUFA, but also the lipid chemical types. (3) The method using dried diet (yeast) mixed with fish oil for the rotifers to enrich n-3HUFA is suitable for large-scale rotifer production mainly for the good effect of HUFA enrichment and avoidance of water contamination.%以褶皱臂尾轮虫(Brachionus plicatilis)为实验动物并设计不同脂肪源饵料,分别为:面包酵母Saccharomyces cerevisice(对照组),微绿球藻Nannochlorpsis oculata(A),5%大豆磷脂+5%鱼油+90%面包酵母(B),10%鱼油+90%面包酵母(C).结果表明:(1)接受不同脂肪源的轮虫的脂肪酸组成显著不同,尤其是高度不饱和脂肪酸(HUFA,20C)含量存在显著差异,说明饵料中HUFA含量对轮虫体内相应脂肪酸的含量有显著影响.投喂饵料C的轮虫具有高含量的n-3HUFA(26.7%),而对照组轮虫的n-3HUFA只有7.56%,所以投喂饵料C使轮虫的脂类HUFA水平得到了强化,提高了轮虫的营养价值.(2)轮虫脂类的HUFA水平不仅由饵料中脂类的相应脂肪酸组成决定,而且轮虫脂类HUFA的提高和强化效果与饵料中HUFA的化学形态密切相关.甘油三酯型饵料HUFA的强化轮虫效果高于磷脂型的HUFA.(3)将富含HUFA的鱼油直接添加在干性饵料如面包酵母中,而不是通过对鱼油乳化后直接强化轮虫,同样能取得良好的强化效果,且操作简便,不易污染水质,适用于轮虫的规模生产.
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