End of project reportData from Cornell University and the University of Illinois in the USA suggested that average daily liveweight gains of 900 to 1000 g/calf/day could be achieved from birth to weaning provided the calf milk replacer (CMR) is formulated to meet the calf’s amino acid requirements for such a rate of gain. Their findings suggested a daily milk replacer DM allowance of 1250 to 1500 g/d with a crude protein content of 26 to 30%. A series of studies were undertaken, at ARINI with home born dairy calves and at Grange Beef Research Centre with purchased dairy calves, to determine the effect of increasing the daily milk replacer DM allowance and or increasing the crude protein content of the CMR on calf performance.The
main outcomes of these studies were
There was no growth or intake response in any of the studies to increasing the crude
protein content of the CMP from 23% to 28%.
Calf growth rates responded to increasing the dailymilk replacer allowance from 600
to 1200 g/day for both home bred and purchased calves. However, the effect was not
significant post-weaning in any of the studies.
In all of the studies (for both home reared and purchased calves) feeding a high level
of CMRdecreased concentrate DM intake. However, the calves concentrate intakes
were similar post-weaning.
The home bred calves with free access to the milk replacer feeders failed to consume
their 1200 g/day allowance. Calves offered 600 or 1200 g of CMR/day had average
consumption of 554 and 944 g/d, respectively, in the milk feeding period.
Feeding a high (1200 g/d) compared to a low level (600 g/d) CMRdiet for the first 56
days had no significant effect on carcass weight or carcass characteristics when
purchased male calves were slaughtered off an ad libitum concentrate diet after 388
days. The final carcass weights were 231 and 240 kg for the respective 600 and 1200
g/d CMR.
Reducing the fat content of the CMRfrom 18% to 12% did not have any effect on
concentrate intake or liveweight gain