AGE OF DAM, SEX AND ENVIRONMENTAL INTERACTIONS AFFECTING PREWEANING AVERAGE DAILY GAINS OF BEEF CATTLE
Open AccessL. R. SCHAEFFER, J. W. WILTON
Canadian Journal of Animal Science, Vol. 54, No. 2, pp. 183-190, 1974
Abstract
Records on 25,571 Angus and 69,058 Hereford calves were used to calculate herd, cow and error components of variance by Henderson’s Method 2. Repeatability of preweaning average daily gain was found to be 0.27 for Angus and 0.33 for Hereford. Best linear unbiased estimates were calculated for age of dam–sex–type of feeding (creep vs. noncreep) and for age of dam–sex–herd performance level subclasses for both Angus and Hereford. Three-way interactions were found to be statistically nonsignificant as were age of dam by type of feeding interactions for both breeds. Age of dam by sex and sex by type of feeding interactions were found to be significant, as were age of dam by herd performance level and sex of calf by herd performance level.