Stability of Aberdeen Angus breeding values in the Czech Republic from 1997 to 2007

Abstract

We predict the stability of breeding values (BVs) for direct effect (DE) and maternal effect (ME) for live weights at 210 days of age in the entire population of purebred Aberdeen Angus cattle in the Czech Republic according to an increase of progeny number in performance recording over a period of 11 years (1997 to 2007) and the course of BVs for DE and ME during the years of observation in animals born until 1997. Furthermore we compare genetic trends of BVs for DE and ME among animals born in different years and detect the level and significance of correlation coefficients among predictions of BVs for DE and ME performed during the years of observation. The animal model and the BLUPF90 programme were used for these predictions. The used model included the effects of animal, sex, contemporary group, dam, age of dam, and permanent environment of dam. The variance of BVs ranged from 4.96 to 10.87 depending on the year of evaluation and whether it was related to maternal or direct genetic effect. The animals were initially assigned to groups according to their BV in 1997, and this ranking was not affected by the BVs predicted in subsequent years. The existence of a negative correlation between direct and maternal effects was confirmed. The significant correlations (P < 0.0001) demonstrated a strong relationship between the BVs predicted in successive years, e.g. the correlation coefficient for the relationship between BVs for direct effect predicted in the last years of the examined period was above 0.9 and that for maternal effect was above 0.8.