大菱鲆幼鱼饲料中浒苔适宜添加量的应用研究

Optimal Dietary Enteromorpha prolifera in turbot(Scophthalmus maximus)

为探讨浒苔在大菱鲆幼鱼养殖饲料中的应用,确定饲料中适宜的浒苔添加量,筛选浒苔在大菱鲆饲料的应用配方,以初始体质量(6.05±0.03)g的大菱鲆幼鱼为试验对象,分别在基础饲料中添加0%(E1,对照组)、5%(E2)、10%(E3)、15%(E4)和20%(E5)的浒苔粉,配制成5种等氮等能的饲料,在循环水系统中进行42d的摄食生长试验。饲喂试验结束后测定大菱鲆的生长、摄食及非特异性免疫力。试验结果显示,添加浒苔粉20%试验组的质量增加率、特定生长率和饲料效率显著低于对照组(P<0.05),而其余各试验组的大菱鲆质量增加率、特定生长率和饲料效率与对照组相比均无显著差异(P>0.05);各试验组的摄食率差异不显著(P>0.05);添加浒苔粉5%试验组大菱鲆头肾巨噬细胞的吞噬活力和巨噬细胞呼吸爆发活力均显著高于其余各试验组(P<0.05)。由此可知,在本试验条件下,在大菱鲆饲料中适当添加浒苔5%时,对其生长和非特异性免疫力具有一定促进作用,但浒苔添加量增加到20%时,大菱鲆幼鱼的生长以及非特异性免疫力均受到抑制。

To study the application of dietary filamentous alga Enteromorpha prolifera in juvenile turbot , the experiment was conducted to determine the effects of dietary E .prolifera on growth ,feeding and nonspecific immune responses .The turbot juveniles with initial weight （6 .05 ＆#177; 0 .03）g were fed five different diets containing green alga E .p roli f era at 0% （E1 ,control group） ,5% （E2） ,10% （E3） ,15%（E4） and 20% （E5） for 42 days .Fish were randomly sampled for analysis of the weight gain rate ,specific grow th rate , feed efficiency rate , food ingestion , macrophage phagocytic activity and macrophage respiratory burst activity .The results showed that the specific growth rate ,growth rate and feed efficiency rate were significantly lower in the E5 group than those in the test group （E1） （P〈0 .05） .There was no significant difference in food ingestion among every group （P〉 0 .05） .The macrophage proliferation activity and macrophage respiratory burst activity were significantly higher in E 2 group than in the other groups （P〈0 .05） .Under the experimental conditions ,there were significantly increase in growth and non‐specific immunity in the turbot fed the diet containing 5% E .prolifera .However ,20% E .prolifera dietary had the negative effects on the grow th and non‐specific immunity in turbot .