Diallel cross in swine production: A review

Abstract

A review of diallel cross and its influence on different genetic and crossbreeding parameters derived in swine production is attempted following its application by various researchers. With different genetic models developed by different researchers from the 1950’s till date, diallel cross methodology and its application in animal breeding, particularly in swine improvement has experienced many modifications and technical innovations derived and developed. The genetic gains derived from diallel cross have two major sources viz. additive (direct and maternal) and dominance genetic effects. The practical importance of these two sources is evaluated, through estimates of average direct genetic, average maternal genetic, general combining ability, specific combining ability, reciprocal, direct heterotic and maternal heterotic effects. In the case of significant reciprocal effect; sex-linked and autosomal effects can be estimated. This review paper tries to cover the different approaches used in optimization of diallel crossing between different available pig breeds in terms of the crossbreeding parameters, as well as the findings of various studies using diallel cross aimed at swine production and improvement.