Evaluating Pre-Weaning Growth of Beef Calves

Abstract
Pre-weaning growth data on 2739 beef calves born at Lincoln and Fort Robinson, the progeny of 187 sires, were analyzed to investigate alternative methods of computing weaning weight. Adjustment factors for sex, inbreeding of calf and dam, age of calf and age of dam were computed. Heritability of gain during the first 130 days of the suckling period was lower than for gain during the last 70 days at both stations. Computing gain in the two periods separately, adjusting gains made in the last period for age and combining these with birth weight would be the most accurate appraisal of weaning weight. The simpler procedure of computing weaning weight as birth weight+200 (average daily gain, birth-weaning) without further adjustment for age was correlated nearly perfectly (0.99) with this more complex measure. Use of the simpler method, with adjustments for sex, inbreeding and age of dam where necessary, yields an accurate measure of weaning weight. Copyright © . .