旨在改进美国油脂化学家协会(The American Oil Chemists'Society,简称AOCS)测定盐酸不溶灰分(AIA)标准方法的上样量和过滤介质,以简化测定步骤、提高测定精度,并通过AOCS改进法与AOCS标准方法测定AIA,比较两种方法的重复性、可加性及准确性,为准确评价肉鸡对饲粮的代谢能(AME)提供可靠的技术.本研究分为两个试验.试验一采用单因素完全随机设计,通过两种方法(AOCS改进法、AOCS标准方法)对6个样品(3个饲粮、3个排泄物)分3个批次测定AIA含量,比较两种测定方法的可重复性;然后,通过两种方法测定6个混合饲粮和6个混合排泄物样品AIA的实际含量,同时,根据混合饲粮和混合排泄物的组成及AIA含量得到其AIA的计算值,采用配对设计比较实测值与计算值的差异以检验两种测定方法的可加性.试验二采用配对试验设计,比较两种方法测定AIA计算13个饲粮AME与全收粪法测定AME的差值,验证两种方法评价饲粮AME的准确性.结果表明,AOCS改进法测定3个饲粮和3个排泄物AIA的总变异系数(TCV)分别在2.13％～5.83％和1.71％～2.83％,而AOCS标准方法测定上述样品AIA的TCV分别在4.69％～15.37％和1.50％～5.79％;AOCS改进法测定6个混合饲粮和混合排泄物AIA实测值和计算值的差值分别在0.004％～0.017％和0.002％～0.029％,而AOCS标准方法测定上述样品实测值和计算值的差值分别在0.037％～0.071％和0.015％～0.072％.AOCS改进法测定AIA评价饲粮AME与全收粪法AME测值相差在0.021～0.251 MJ·kg-1 DM,而AOCS标准方法测定AIA评价饲粮AME与全收粪法AME测值相差0.025～1.799 MJ·kg-1 DM.综上所述,从测定AIA的重复性、可加性及对AME测定值的准确性上,AOCS改进法均优于AOCS标准方法.
Comparative Study on the Accuracy of Dietary Metabolizable Energy Influenced by Methods of Acid Insoluble Ash in Broilers
The objective of this study was to optimize the loading sample size and filter medium of The American Oil Chemists'Society(AOCS)standard method for the determination of acid insoluble ash(AIA)to simplify the assay procedure and improve the accuracy.The repeatability,additivity and accuracy of AIA determined with AOCS modified method and the AOCS standard method were compared to obtain a reliable technique for accurately evaluating the dietary appar-ent metabolizable energy(AME)for broilers.Two experiments were conducted in the current study.In experiment 1,three batches determination of AIA content for each of 6 samples(3 diets,3 excreta)using two methods(AOCS modified method,AOCS standard method)in a completely randomized design was to compare the reproducibility of the 2 methods.Then,the ac-tual AIA content of 6 mixed diets and 6 mixed excreta samples were determined by the 2 meth-ods.Meanwhile,the AIA value was calculated according to the composition of the mixed diet and mixed excreta and their AIA content.The difference between the determined and the calculated values was compared to test the additivity of the 2 methods by a paired experimental design.In experiment 2,a paired experimental design was used to compare the difference between the calcu-lated AME of 13 diets using two AIA determination methods and the AME measured by the total collection method to test the accuracy of the 2 methods to evaluate the dietary AME.The results showed that the total coefficient of variation(TCV)of AIA determined by the AOCS modified method in each of 3 diets and 3 excreta samples ranged from 2.13％to 5.83％and 1.71％to 2.83％,respectively,while the TCV of AIA determined by the AOCS standard method ranged from 4.69％to 15.37％and 1.50％to 5.79％,respectively.The difference between the deter-mined and calculated AIA values of 6 mixed diets and 6 mixed excreta by the AOCS modified method ranged from 0.004％to 0.017％and 0.002％to 0.029％,respectively.The difference between determined and calculated values of those samples by AOCS standard method ranged from 0.037％to 0.071％and 0.015％to 0.072％,respectively.The differences of 0.021 to 0.251 MJ·kg-1 DM were observed between the AME evaluated by AIA determined with the AOCS modified method and AME determined by total collection.Whereas the differences of 0.025 to 1.799 MJ·kg-1 DM were observed between AME evaluated by AIA determined with the AOCS standard method and AME determined by total collection.In conclusion,the AOCS modi-fied method is superior to the AOCS standard method in the reproducibility and additivity of AIA determination and in the accuracy of evaluating dietary AME.
万方数据
维普
