SNP-based mate allocation strategies to maximize total genetic value in pigs

Background: Mate allocation strategies that account for non-additive genetic efects can be used to maximize the overall genetic merit of future ofspring. Accounting for dominance efects in genetic evaluations is easier in a genomic context, than in a classical pedigree-based context because the combinations of alleles at loci are known. The objective of our study was two-fold. First, dominance variance components were estimated for age at 100 kg (AGE), backfat depth (BD) at 140 days, and for average piglet weight at birth within litter (APWL). Second, the efciency of mate allocation strategies that account for dominance and in breeding depression to maximize the overallgenetic merit of future ofspring was explored. Results: Genetic variance components were estimated using genomic models that included inbreeding depression with and without non-additive genetic efects (dominance). Models that included dominance efects did not ft the data better than the genomic additive model. Estimates of dominance variances, expressed as a percentage of additive genetic variance, were 20, 11, and 12% for AGE, BD, and APWL, respectively. Estimates of additive and dominance single nucleotide polymorphism efects were retrieved from the genetic variance component estimates and used to predict the outcome of matings in terms of total genetic and breeding values. Maximizing total genetic values instead of breeding values in matings gave the progeny an average advantage of &‡22;0.79 days, &‡22;0.04 mm, and 11.3 g for AGE, BD and APWL, respectively, but slightly reduced the expected additive genetic gain, e.g. by 1.8% for AGE. Conclusions: Genomic mate allocation accounting for non-additive genetic efects is a feasible and potential strat&‚09; egy to improve the performance of the ofspring without dramatically compromising additive genetic gain.

Article en accès ouvert disponible ici (s’ouvre dans le site de l’éditeur)