Truncation Points for Selection in a Population with Overlapping Generations

Abstract

Simple procedures for computing the truncation points of selection such as (1) predicted genetic values on truncation points and (2) average genetic values of selected parents should be on the same level for each age class of parents in a population with overlapping generations, are presented. To illustrate these procedures, the path of bulls' dams in a dairy cattle population was taken as a choice for a numerical example. The results were compared with two other selection methods, intra-age selection and selection on common truncation point on phenotypic values to assess their practicability in optimizing the age structure and prediction of genetic response to truncation selection. The problems in pursuing such selection policies are also discussed.