RELATIONSHIPS AMONG ESTIMATES OF INBREEDING DEPRESSION, DOMINANCE ANDADDITIVE VARIANCE FOR LINEAR TRAITS IN HOLSTEINS

Estimates of dominance and additive variances were obtained for 14 lin ear traits. The data included 600 678 first parity records on 14 linea r traits in Holsteins. The model included management groups, age at ca lving, additive and dominance effects, and regression on inbreeding pe rcentage. The estimate of the dominance variance was 9.8% of the pheno typic variance for body depth: 8.0% for strength, 6.9% for stature, an d was less than 5% for the remaining traits. The additive variance ran ged from 12.2% for foot angle to 45.3% for stature. No clear relations hip was found between the estimates of dominance and additive variance . larger negative estimates of the inbreeding depression were associat ed with higher estimates of the dominance variance.