Animal Science Department


Date of this Version

January 1980


Published in J Dairy Sci 1980, 63:120-132. Copyright © 1980 The American Dairy Science Association. Used by permission.


Variances and covariances for herdyear, sire, and residual effects were estimated for 10 standard type traits and milk yield from type records on 12,838 Brown Swiss cows and milk records on 5,911 of these. A total of 712 sires and 824 herds was involved. The model was a random two-way, cross-classified model (herd-year and sire of cow) with no interaction. Covariances with descriptive type traits scored in categories as present or absent also were estimated as were variance-covariance matrices for descriptive type traits when each category was a separate trait. Genetic correlations of standard type traits with final classification score were large and positive. Genetic correlations of desirable categories of descriptive type traits with final classification also were positive. Standard type traits and final score had positive genetic correlations with milk yield generally ranging from .18 to .29 except for feet and legs .03.