Journal of Dairy Science, Vol 73, Issue 1 191-197, Copyright ©
1990 by American Dairy Science Association
Prediction of transmitting abilities for Holstein type traits
P. M. Vanraden, E. L. Jensen, T. J. Lawlor and D. A. Funk
Department of Dairy Science, University of Wisconsin,
Madison 53706.
Heritabilities and genetic and phenotypic correlations among 14 linear
type traits were estimated from Holstein Association data by multiple
trait REML. Data used for parameter estimation were records of
779,391 daughters of 871 sires included in the January 1988 sire
evaluation. Each daughter was represented by her appraisal closest to
30 mo of age. Highest heritability was .37 for stature, and lowest
was .10 for foot angle. Gains in reliability from using correlated
traits in multiple trait prediction were large for some traits (up to
60% for foot angle for cows). Final score variance parameters were
estimated from 953,596 records, which were 43% of records included in
the national sire evaluation. Sire models that adjusted or did not
adjust for merit of mates were compared. Heritability of final score
was .27 with adjustment for merit of mates by subtraction of
predicted transmitting ability of dam from daughter's record compared
with .29 if mate was ignored. Evaluations for type for several
popular older sires were reduced moderately by adjustment for merit
of mates, but estimated genetic trend increased slightly. An improved
genetic grouping procedure that considers group effects as inherited
was adapted for use in sire models. Parameter estimates and models
presented were implemented by the Holstein Association for computing
July 1988 genetic evaluations for linear traits and final score.
