酵母硒对凡纳滨对虾生长和抗氧化性能的影响

Effects of yeast selenium on the growth and antioxidative performance in Litopenaeus vannamei

【目的】研究饲料中添加不同水平酵母硒对凡纳滨对虾生长和抗氧化性能的影响.【方法】选取初始体质量为(0.41±0.01)g的凡纳滨对虾Litopenaeus vannamei 720尾,随机分为6个试验组,每组3个重复,每个重复40尾虾,在室内循环水养殖系统(容积250 L)中进行为期56 d的生长试验.在基础饲料中分别添加硒(酵母硒)0、0.15、0.30、0.45、0.60、1.00 mg·kg-1,制成6种不同硒水平的半纯化饲料,实测饲料硒质量分数分别为0.25、0.41、0.56、0.68、0.84、1.20 mg·kg-1.【结果和结论】结果表明,添加酵母硒对凡纳滨对虾增质量率、特定生长率、饲料系数、成活率均无显著影响(P>0.05),随着饲料硒水平的增加,凡纳滨对虾的增质量率和特定生长率不断升高,在0.84 mg·kg-1硒组达到最大值.各试验组对虾肝胰腺超氧化物歧化酶和总抗氧化能力均高于对照组,而丙二醛含量均低于对照组,但差异不显著(P>0.05).以增质量率和特定生长率为评价指标,通过二次线性回归分析表明,在该试验条件下凡纳滨对虾饲料中硒含量为0.98 mg·kg-1时其生长性能最高.

[Objective] The effects of dietary yeast selenium on the growth and antioxidant performance were studied in Litopenaeus vannamei.[Method] Seven hundred and twenty healthy Litopenaeus van-namei with an initial average body mass of （0.41 ±0.01） g were randomly stocked into 6 groups with 3 replicates per group and 40 shrimps per replicate in re-circulated water system .The basal diet was sup-plemented with 0, 0.15, 0.30, 0.45, 0.60 and 1.00 mg· kg -1 selenium （yeast selenium） respectively and these shrimps were fed with 6 semi-purified diets containing graded levels of 0.25, 0.41, 0.56, 0.68,0.84,1.20 mg· kg -1 of selenium, respectively for 56 d.[Result and conclusion] The results showed that mass gain rate （MGR）, specific growth rate （SGR）, feed conversion rate （FCR）, survival rate （ SR） had no significant difference among all groups （ P〉0.05） , but with the increase of yeast sele-nium levels, MGR and SGR increased and the highest value was found in the 0.84 mg· kg -1 group.The total antioxidative capacity （ T-AOC） and superoxide dismutase （ SOD） of shrimp in hepstopsncreas were higher than those of the control group , while the malondialdehyde （ MDA） content was lower than that of the control group .But there were no significant differences （ P〉0.05 ） .A quadratic linear regression a-nalysis showed that using MGR and SGR as response criteria in cultured condition , the optimum dietary selenium content for the highest growth in Litopenaeus vannamei was 0.98 mg· kg-1 of dietary mass.