Published online by Cambridge University Press: 02 September 2010
Over 3 years a total of 204 bucket-reared calves (from Holstein/Friesian dams) and 187 suckled calves (from Hereford × Friesian dams) were monitored during the first 9 or 6 months of life respectively. Within each rearing system there were approximately equal numbers of calves sired by Charolais and Hereford bulls and also about equal numbers of heifer and steer calves. All breeds and sexes within each rearing system were managed as a single group.
Differences in daily live-weight gain from arrival (January) for the bucket-reared calves and from birth (April) for the suckled calves through to the autumn were significantly different at 0·66 and 1·01 kg/day respectively (P < 0·001). By comparison, differences in growth rate between sex and breed within each rearing system were small. Hereford cross calves from both systems however carried significantly more condition in the autumn compared with Charolais crosses (P < 0·01).
The results suggest that when animals are reared on the same plane of nutrition and given similar management, differences in initial growth rate between early and late maturing breeds and sexes may be less than those perceived by commercial producers the views of whom are influenced by the fact that the types are often managed differently in practice.