Mate Selection for Joint Control of Response and Inbreeding in Closed Pig Breeding Herds

Abstract

Simple mate selection procedures for the joint control of response to selection and inbreeding were evaluated in a dynamic pig breeding population using stochastic simulation. The simulated populations modelled a closed breeding herd of moderate size (approx. 270 sows), characterised by overlapping generations and continuous cycles of performance testing and selection. Two studies were conducted: 1) where selection was for a single trait under three different heritabilities (ST), and; 2) where selection was for an aggregate genotype under three different breeding objectives (MT). Trait heritabilities for ST studies were 0.1, 0.35 and 0.6, and breeding objectives for MT studies defined general purpose (GP), terminal sire (TS) and maternal (MAT) selection lines.