Correlations of various direct and maternal effects for calving ease.

Multitrait restricted maximum likelihood methods were used to estimate heritabilities of direct and maternal effects for calving ease and their genetic correlation for heifers and cows. Heritabilities were 4.9% for direct effects and 4.8% for maternal effects of heifers and 1.1% and .7% for cows. Genetic or direct maternal correlations were--.40 in heifers and .07 in adult cows. Restricted maximum likelihood methods also were used to estimate the genetic correlation (.995) between direct effects for calving ease measured in heifers and in cows.