When calves are unable to suckle, it is thought that they begin to develop abnormal oral behaviour, although it is not known whether this behaviour occurs because the calf needs access to its dam or whether a multiple suckling system would suffice to prevent the behaviour from developing. An initial experiment examined the behaviour of calves that suckled their own dam or another cow for 15 minutes each day and compared that to the behaviour of artificially-reared calves that had no opportunity to suckle. Calves that were allowed to suckle consumed more milk than calves that were reared artificially. Cross-sucking behaviour was greater in non-suckled (artificially reared) calves than in suckled calves. Cross-sucking was at its highest frequency 1 minute after the end of milk feeding in the non-suckled calves, and declined linearly to negligible levels at 13 minutes after milk feeding had occurred. Most of the cross-sucking behaviour (78 %) was directed at the inguinal (udder/scrotal) region of other calves. For suckled calves, however, more of the cross-sucking behaviour (81 %) was directed at the mouths of other calves. Calves that had been artificially reared spent more time consuming concentrate feed and consumed more feed than suckled calves, suggesting that food ingestion could provide a replacement stimulus. A second experiment found that before weaning, the time calves spent licking their pen or bucket increased until feed intake was sufficient to stimulate significant amounts of rumination. After weaning, the behaviours decreased. Conclusions stated that cross-sucking of artificially-reared calves could be prevented by providing short access to either the calf’s dam or another cow for two short periods each day. When a cow was absent and no suckling could occur, the calves licked inanimate objects repeatedly until the consumption of solid feed was sufficient to stimulate rumination.