A note on the post-weaning performance of autumn-born suckled calves

Thirty-nine Charolais × (Hereford × Friesian) autumn-born calves, whose dams had been given either 92 or 63 MJ metabolizable energy per day during winter and subsequently grazed at two sward heights, either 4-8 (short) or 7·6 (tall) cm from 6 May until weaning on 3 July in a factorially designed experiment, were used to examine the effect of pre-weaning performance on post-weaning growth rates. Following weaning the calves grazed as one group for a period of 76 days. There was no effect of winter treatment on postweaning performance. From weaning until 76 days later there was a significant (P < 0·01) effect of pre-weaning sward height on live-weight gain (0·94 and 0·69 kg/day for the calves from the short and tall swards respectively), so that the 41 kg liveweight difference at weaning was reduced to 22 kg (P > 0·05) with compensatory growth occurring independently of the height of the sward grazed.