Department of Tropical Veterinary Science, James Cook University of North Queensland, Queensland, Australia.
Theor Appl Genet. 1983 Mar;64(4):339-44. doi: 10.1007/BF00274177.
Conventional selection index theory assumes that the total merit or profitability of animals is a linear function of measurable traits. However, in many cases merit may be a non-linear function of these traits. A linear selection index can still be used in this situation but the optimum index depends on the selection intensity to be used and on the number of generation over which the selection response is to be maximized. Nonlinear selection indices have been suggested but these result in a lower selection response than the best linear index. Linear selection indices suggested in the past are shown to correspond to the optimum linear index for either a very small selection response or, in the case of restricted indices, a very large selection response. The economic value of a trait may depend on management decisions taken by the farmer. In this situation the economic values should be calculated assuming that the management decisions taken maximize profit given the present genetic value of the animals.
传统的选择指数理论假设动物的总优点或盈利能力是可衡量特征的线性函数。然而，在许多情况下，优点可能是这些特征的非线性函数。在这种情况下仍然可以使用线性选择指数，但是最优指数取决于要使用的选择强度以及要最大化选择响应的世代数。已经提出了非线性选择指数，但这些指数导致的选择响应低于最佳线性指数。过去提出的线性选择指数被证明对应于非常小的选择响应的最优线性指数，或者在受限指数的情况下，对应于非常大的选择响应的最优线性指数。特征的经济价值可能取决于农民做出的管理决策。在这种情况下，应假设管理决策是在考虑动物当前遗传价值的情况下使利润最大化来计算经济价值。
