Contributions of Discriptively Coded Type Traits to Longevity of Holstein Cows

Official type classifications and production records of Holstein cows calving between January 1, 1967, and June 1, 1976, were used to estimate contributions of appraisals in first lactation of descriptive type traits to first lactation and lifetime production, herdlife, and first calving intervals. Herdlife, production variables, and calving intervals were deviations from contemporary averages. Contributions of individual type components to these were estimated from least squares constants adjusted for all other descriptive type traits and for linear and quadratic effects of final score, age at first calving, herdlife opportunity, stage of lactation, and age when classified.