The use of hay or oaten grain to fatten weaner heifers grazing dry summer pasture.

Hereford weaner heifers (9 months old, mean fasted live weight 201 kg) were fed supplements of oaten grain (0.8 or 1.6% of live weight) or ad libitum pasture hay or lucerne hay, while grazing abundant dry standing pasture. All supplemented groups gained live weight significantly faster than an unsupplemented, pasture only group. The 0.8% oats, 1.6% oats, lucerne hay, pasture hay and unsupplemented heifers gained live weight at 0.4, 0.7, 0.6, 0.3 and 0.1 kg/day, respectively. In the oats and lucerne treatments, 80-100% of the heifers had a fat depth of >6 mm at the end of the feeding period compared with only 27% of the pasture hay and unsupplemented heifers. Following a 7 month common grazing period after the end of supplementation, 28-41% of the liveweight advantage from feeding was lost due to compensatory gain, but all supplemented groups were still significantly heavier than the control group.