饲料中添加太子参提取液对大黄鱼成活和生长的影响

Effects of Pseudostellaria heterophylla Extract Supplementation on Survival and Growth Performance of Large Yellow Croaker

在水温24~26℃下,将体质量(34.05±8.23)g的大黄鱼Larimichthys crocea饲养在循环水养殖系统1.5T的桶中,投喂添加0.5%、1.0%、1.5%和2.0%太子参Pseudostellaria heterophylla提取液的饲料,分析其对大黄鱼成活率、生长和形体指标的影响。太子参粉末置圆底底烧瓶中,加80%乙醇,水浴90℃回流提取3h,趁热过滤,残渣用95℃超纯水浸提4h后过滤,两次滤液混合、浓缩,去除水分,即为太子参提取液(浓度为40mg/mL)。120d的饲养结果显示:太子参提取液显著提高了大黄鱼养殖成活率(P<0.05),1.0%组的养殖成活率(88.1±5.3)%最高;太子参提取液对大黄鱼有促生长和改良形体指标的功效,后期更为明显,试验120d时,0.5%组大黄鱼体重绝对增加率[(0.25±0.004)g/d]、绝对增长率[(0.026±0.006)cm/d]和增积量(0.0067±0.0004)显著大于其他组(P<0.05),肥满度(1.43±0.49)%和肝体比(1.54±0.31)%显著低于对照组(P<0.05),脏体比[(1.00±0.14)%]显著低于其他各组(P<0.05)。结果表明,太子参提取液能提高大黄鱼的成活率、食物的消化吸收率,添加量在0.5%~1.0%之间为宜,且投喂时间越长,效果越佳。

Large yellow croaker Larimichthys crocea with body weight of(34.05±8.23)g was reared in a 1.5 t barrel of a recirculating aquaculture system and fed diets supplemented with extract of Pseudostellaria heterophylla at a dose of 0.5%,1.0%,1.5%and 2.0%at water temperature of 24~26℃for 120 days to investigate effects of the extract on the survival rate,growth and body parameters of large yellow croaker.The extract of Pseudostellaria heterophylla(40 mg/m L)was prepared by the following:80%ethanol was added into the powder of Pseudostellaria heterophylla in a flask with round bottom,refluxed at 90 for 3 hours in water bath,and filtered while heated,and the residues were extracted with ultra-pure water at 95℃for 4 h,and then mixed and concentrated the filtrate twice to remove water.The results showed that Pseudostellaria heterophylla extracts led to be significant increase in survival rate of large yellow croaker(P<0.05),with the maximal survival rate(88.1±5.3)%in group 1.0%.The extracts of Pseudostellaria heterophylla had the effect of promoting growth and improving physical indices of large yellow croaker,especially in the later stage.There were significantly higher absolute weight gain rate of[(0.25±0.004)g/d],absolute growth rate[(0.026±0.006)cm/d]and the amount of product(0.0067±0.0004)in 120 d in group 0.5%than those in other groups(P<0.05),significantly lower relative condition factor(1.43±0.49)%and hepato-somatic index(1.54±0.31)%than those in the control group,and significantly lower viscera-somatic index[(1.00±0.14)%]than that in other group(P<0.05).The findings indicate that Pseudostellaria heterophylla extract as feed additive leads to improve the immunity,digestion and absorption of the large yellow croaker,with the optimal dose between 0.5%and 1.0%,better in the longer feeding period.