Effects of different pretreatment methods on determination of microelements in feed.

[Objective] To study the effects of different pretreatment methods on determination of microelement in feed,and thus find the best pretreatment method for determination of each microelement in feed.[Method] The samples(concentrated feeding stuff and fodder) were pretreated through three methods,that is,dry incineration method,HNO3-HClO4 wet-decomposition method and microwave digestion method.Then the content of seven kinds of microelement(Al,Ca,Cu,Fe,Mn,Se and Zn) was determined by inductively coupled plasma atomic emission spectrometer(ICP-AES).[Result] These three methods were all suitable for the determination of Cu,Mn and Zn in concentrated feeding stuff and the determination of Cu and Ca in fodder.The content of Cu and Ca was higher in fodder detected by HNO3-HClO4 wet-decomposition method.The microwave digestion method was suitable for the determination of Al and Ca in concentrated feeding stuff and the determination of Al,Fe,Mn and Zn in fodder.The dry incineration method was fit for the determination of Fe in concentrated feeding stuff.[Conclusion] The content of different microelements should be determined after the feed is treated with different pretreatment methods.