ICP－MS法测定大菱鲆饲料中微量元素的含量

摘要

采集辽宁葫芦岛地区10个大菱鲆养殖场的13份配合饲料样品和4份冰鲜野杂鱼样品，利用微波消解－电感耦合等离子体－质谱法（ ICP－MS）检测样品中11种微量元素Cu、Zn、Fe、Mn、Co、Se、Cr、Pb、Cd、Hg、As的含量。结果表明：11种微量元素在大菱鲆配合饲料中的平均浓度顺序为Fe（719 mg／kg），Zn（122 mg／kg），Mn （32．4 mg／kg），Cr（8．35 mg／kg），Cu（7．31 mg／kg），Se（1．48 mg／kg），Pb（0．503 mg／kg），Cd（0．462 mg／kg），Co （0．422 mg／kg）和Hg（0．036 mg／kg）。除Cr外，配合饲料中微量元素水平均高于冰鲜鱼，差异极显著（P＜0．01）；饲料质量评价结果显示，大菱鲆配合饲料中微量元素含量的变异程度比较稳定，潜在有毒元素Pb、Cd、Hg、As的含量均低于水产配合饲料安全限量，且大多数必需元素的最低含量均高于推荐剂量；相对于冰鲜野杂鱼，配合饲料能够为大菱鲆生长提供更为充足的必需元素，但Fe、Cr、Se存在超标现象。%A total of 13 commercial feeds and 4 fresh frozen trash fish( TF) samples were collected from 10 turbot( Scophthalmus maximus.L) farms located in Huludao of Liaoning,then the contents of 11 trace ele-ments i.e.Cu,Zn,Fe,Mn,Co,Se,Cr,Pb,Cd,Hg and As in the samples were determined by ICP-MS method. The results showed that the mean trace element concentrations in the compound feed followed the order:Fe (719 mg/kg)>Zn(122 mg/kg)>Mn(32.4 mg/kg) >Cr(8.35 mg/kg)>Cu(7.31 mg/kg)>Se(1.48 mg/kg)>Pb(0.503 mg/kg)>Cd(0.462 mg/kg)>Co(0.422 mg/kg)>Hg(0.036 mg/kg).The levels of the analyzed elements in compound feeds were significantly higher than those in TF( P<0.01) except for Cr.Evaluation of the feed quality suggested that trace element levels in compound feed were relatively stable,the contents of potentially toxic elements i.e.Pb,Cd,Hg,As were all below the safety limits for aquafeeds and the lowest levels for most essential elements were higher than the recommended dose.Compared with TF,these results show that the compound feed could provide more sufficient essential elements for turbot growth,however,there were three elements i.e.Fe,Cr,Se exceeded the maximum limits.