A Comparison of Restricted Selection Procedures Based on Restricted Best Linear Unbiased Prediction of Breeding Values

Abstract Text: We compared two different restricted selection procedures. A Monte Carlo simulation of a closed herd of 10 males and 100 females was carried out to examine response to selection over 10 generations. The breeding objective was to maximize the genetic gain in trait 1 (T1), with constraint of no change in trait 2 (T2). The heritabilities of the two traits were all combinations of 0.1, 0.3, and 0.5. Genetic and environmental correlations between T1 and T2 were all combinations of –0.7, 0.0, and 0.7. Two restricted BLUP methods were used: the same restriction on all animals (AR-BLUP) and constraint with only candidates for selection (PR-BLUP). The genetic gains in T1 using PR-BLUP were always larger than by AR-BLUP. Responses to selection in T2 by applying PR-BLUP were smaller than by AR-BLUP. We concluded PR-BLUP to be more effective than AR-BLUP for selection with constraint.

Keywords: selection with constraint

restricted BLUP