Including Coefficients of Inbreeding in BLUP Evaluation and Its Effect on Response to Selection

H. Mehrabani-Yeganeh, J.P. Gibson and L.R. Schaeffer
J. Anim. Breed. Genet. (2000) 117:145-151

Abstract

Stochastic simulation was used to study the effect on selection response of accounting for inbreeding versus ignoring it in the construction of the inverse of the relationship matrix used in mixed model equations (MME) to obtain BLUP of breeding values.  Three different heritabilities of 0.10, 0.25, and 0.50 and two different family structures were used.  Selection of replacement animals was based on best linear unbiased predictors (BLUP) of breeding values using an animal model.  Average inbreeding coefficients (F) were in the range of 0.4-0.5 after 11 generations of selection.  Even with such high inbreeding levels, no significant differences in selection responses were found between accounting or ignoring F in MME construction over the range of heritabilities and family structures.