Corrective Mating Methods in Context of Breeding Theory

The mating practice known as corrective mating is described in terms of a multi-trait selection method where at least one trait has a measurement scale nonlinear in its relationship with total merit. Nonrandom mating methods may be viewed as the selection of mates according to a set of criteria, conditional on a preselected potential parent. Potential mates may be ranked, when total merit is defined as a quadratic function of at least one component trait, by the estimated breeding value of the expected progeny from each possible mating instead of the estimated breeding value of each candidate parent, as would be for selection independent of the possible mates. The index for total merit of the mating will have the usual properties of the selection index. Development of selection methods to rank mating combinations which include traits each with possibly a nonlinear relationship with total merit will require a precise definition of total merit and a determination of the nonlinear relationship, genetic or phenotypic, between each trait and total merit.