In some areas of the world, tail docking dairy cattle is a common procedure. The typical method is to use a rubber ring. The belief is that this procedure improves hygiene and reduces the risk of mastitis; however, this is not supported by scientific research. The current study was conducted to compare the responses of calves that were either tail docked using a rubber ring or a docking iron. A control group was also included, which were exposed to same restraint, but were not tail docked. The results indicated that tail grooming increased up to five days after the rubber ring was applied. The calves with the rubber ring also had a higher frequency and shorter bouts of standing and lying than the calves that were docked with an iron and the control group. Other than one hour after the rubber ring was applied, where these calves had a significantly higher cortisol concentration than the control group, cortisol responses and other behavioural responses of pain (including vocalizations) did not differ among the groups. There were no differences in behaviour between the control group and iron-docked group. Milk intake, weight gain, body temperature and feces score (degree of diarrhoea/blood) did not differ among the groups. In conclusion, using rubber rings for tail docking did not result in a greater behavioural and physiological response than docking with a docking iron. The authors point out that the long-term effects need to be investigated.