Adams R S
J Dairy Sci. 1975 Oct;58(10):1538-48. doi: 10.3168/jds.S0022-0302(75)84750-3.
Trace element content of feeds is extremely variable compared to total digestible nutrients or protein. Differences are wide between low and high values for many trace elements within a given type of feed. Coefficients of variation for forages range from 42 to 100%. Summary data are given for both major and trace elements. Problems in supplementation are discussed. Amounts for some elements are skewed with relatively few samples around the mean and over 60% below the mean. Suggested mineral allowances for dairy cows are listed. Under current supplementation, zinc is the trace element most likely to be limiting and manganese the least likely. Iron, copper, cobalt, and iodine may be limiting in some cases. Needs of research and applied nutrition are presented.
与总可消化养分或蛋白质相比，饲料中的微量元素含量变化极大。对于给定类型的饲料，许多微量元素的低值和高值之间差异很大。牧草的变异系数在42%至100%之间。给出了常量元素和微量元素的汇总数据。讨论了补充方面的问题。一些元素的数据存在偏差，围绕平均值的样本相对较少，超过60%低于平均值。列出了奶牛的建议矿物质供应量。在当前的补充情况下，锌是最有可能受限的微量元素，而锰最不可能受限。在某些情况下，铁、铜、钴和碘可能会受限。提出了研究和应用营养方面的需求。
