饲料中酵母免疫多糖对七彩神仙鱼仔幼鱼非特异性免疫的影响

该研究采用在饲料中添加0～2500 mg·kg^-1的酵母免疫多糖的方法,对900尾七彩神仙鱼仔幼鱼血清的替代补体活力、溶菌酶活力和白细胞吞噬活性影响进行了研究.结果表明,当饲料中酵母免疫多糖添加剂量达到500 mg·kg^-1(Ⅴ组)以上时,七彩神仙鱼仔幼鱼血清替代补体活力、溶菌酶活力和白细胞吞噬活性均开始显著高于对照组(P<0.05),且同一水平随时间的增加而升高.添加量达2000mg·kg^-1(Ⅷ组)及以上时,随着饲料中的酵母免疫多糖添加量的进一步增加,各组数据反而呈下降变化趋势.可见饲料中适量添加酵母免疫多糖能够提高七彩神仙仔幼鱼的非特异性免疫力,缺乏和过量都会对七彩神仙仔幼鱼带来不利影响.

Influence of dietary yeast immune polysaccharide on non-specific immunity of larvae and juveniles Symphysodon aequifasciatus

A feeding trial was conducted to evaluate the effects of dietary yeast immune polysaccharide on non-specific immunity of larvae and juveniles Symphysodon aequifasciatus with the extension to the yeast immune polysaccharide in feed(0-2 500 mg·kg^-1). When the supplementation ratio reached 500 mg·kg^-1 (group Ⅴ),the alternative complement pathway(ACP)activity,serum lysozyme activity,phagocytosis index(PI)and phagocytosis percentage(PP)of the fish were significantly better than those of the control (P<0.05),and they increased over time in the same level.And then the non-specific immune index dropped with the increase of dietary yeast immune polysaccharide above 2 000 mg·kg^-1 (group Ⅷ).So it could be concluded that addition of propriety yeast immune polysaccharide will increase the non-specific immunity of the juvenile fish,but without or with overdose of yeast immune polysaccharide will be harmful to the health of fish.