Rearing of dairy cattle 2. Weaning calves according to their concentrate intake

SUMMARY British Friesian dairy female calves were offered once daily either 320 or 480 g of milk substitute reconstituted in warm water. Weaning took place when calves were consistently eating 400, 650 or 900 g/day of concentrates. The number of days taken to reach weaning was greater with calves offered 480 g than with calves offered 320 g of milk substitute per day. Calves with a high initial live weight achieved the required concentrate intake and were therefore weaned sooner than smaller calves. A fall in energy intake occurred immediately after weaning and this was greatest in calves previously offered 480 g/day of milk substitute. The treatments had no significant effect on the total intake of concentrates and hay over the 8 weeks of the experiment. Increasing the amount of milk substitute from 320 to 480 g/day increased total feed costs, and feed costs per kg live-weight gain. Increasing the required level of concentrate intake at weaning also increased total feed costs and feed costs/kg live-weight gain, but to a lesser extent. The results suggest that it is preferable to feed dairy replacement calves only 320 g of milk substitute in a once-daily feeding system. Weaning can be successfully under-taken when the calves are consistently eating 400 g/day of concentrates.