SELECTION INDEXES WITHOUT ECONOMIC WEIGHTS FOR ANIMAL BREEDING

Abstract

The expected responses of five methods of constructing selection indexes without using economic weights were compared by application to data on growth rate and feed efficiency in swine. One method based on the product of phenotypic values as an index can be used when no estimates of genetic and phenotypic parameters are available and when the breeder considers all traits to be of nearly equal importance. A second method using ’desired gains’ allows the breeder to specify that different traits are of different importance without doing so in economic terms. The remaining three related methods, based on the principles of multivariate statistics, were judged unsatisfactory for most animal breeding programs.