Effect of udder type and calving assistance on weaning traits of beef and dairy×beef calves

Abstract

The effects of udder type, calving assistance (CA) and other factors on preweaning average daily gain (ADG) and weaning weight of beef composites were analysed. Cows with medium or large, well attached udders weaned faster growing and heavier ( P<0.05) calves than cows with small udders or bottle shaped teats with pendulous (BOT) type udders. Cows that were assisted at calving, weaned calves that grew 7.5% slower ( P<0.05) preweaning and were 13.2 kg lighter ( P<0.05) at weaning compared to calves from unassisted cows. Compared to the weaning weights of calves from unassisted cows with BOT type udders, cows with light pull calves and BOT type udders weaned calves that were 26.2 kg lighter, and assisted cows with BOT udders weaned calves that were 26.7 kg lighter at weaning. The decreases ( P<0.05) between assisted and unassisted calves in beef synthetic 1 (BS), BS2 and dairy beef synthetic (DBS) were 9.8, 8.0 and 5.1%, respectively, for preweaning ADG and 8.2, 6.6 and 3.4%, respectively, for weaning weight. The DBS appeared to compensate for the set back of a difficult calving by providing a better nutritional environment for calves than the beef composites. Visual scoring of udders at calving is a practical method of estimating milking ability of and can be used as a tool to cull inefficient cows.