In pig and poultry breeding programs, the ultimate goal is to improve performance of the crossbred production animals, using selection in the purebred parental lines. Response to selection for crossbred performance can be increased by using genomic prediction models that include dominance, concludes Hadi Esfandyari in his PhD thesis “Genomic selection for crossbred performance”. He successfully defended his thesis on February 12th in the Aula of Wageningen University.
Crossbreeding programs are used intensively in livestock production systems. The aim of selective-breeding programs in many of these systems is to maximize crossbred performance (CP), where selection is carried out within pure-lines using data from purebred animals. Genomic selection (GS) can be used to select purebreds for CP. The overall objective of this PhD project was to assess the possibilities of using dominance in genomic crossbreeding programs. Dominance is important in crossbreeding programs as it is the likely genetic basis of heterosis (improved performance of hybrid offspring), and causes incomplete correlation between purebred and crossbred performance. Using simulated data, it was found that the use of a dominance model in genomic prediction increases the accuracy of estimated breeding values. This result shows that dominance models can be used to accelerate genetic progress in pig and poultry breeding. The result was confirmed using real data on purebred Landrace and Yorkshire pigs, provided by the Danish Pig Research Centre.
This thesis is the result of a fruitful collaboration between the Animal Breeding and Genomics Centre (ABGC) of Wageningen University and the Department of Molecular Biology and Genetics of Aarhus University, Denmark. Hadi was supervised by dr. Anders C Sørensen, dr. Piter Bijma, and prof. dr. Johan van Arendonk. The thesis was part of the Erasmus Joint Doctorate Program “EGS-ABG”.