ESTIMATES OF VARIANCE COMPONENTS FOR HOLSTEIN-TYPE TRAITS

Abstract

Sire and error variances and covariances for 27 conformation traits were estimated from 424 875 Holstein-Friesian cows classified since June 1976. Estimates were obtained by Henderson's new method (Diagonal-MIVQUE) with a model that included 46 age by parity groups, 10 stage of lactation groups, herd-round-classifier effects, and nine covariates of dam's type and sire effects. Heritabilities were generally low from 0.10 for feet and legs to 0.29 for capacity, and from 0.05 for rear heel to 0.42 stature. Final class had a heritability of 0.17 and was highly correlated with traits related to mammary system (0.62–0.94). A multiple trait analysis of type could utilize the estimates from this study. Key words: Genetic parameters, type traits, Henderson's new method