Cortisol responses of calves to two methods of disbudding used with or without local anaesthetic.

Cattle are disbudded or dehorned using a variety of methods. In this study, plasma cortisol concentrations were used to monitor distress in 6-week-old Friesian calves during the 9 hours following disbudding. Disbudding was carried out with a cautery iron or a dehorning scoop, with or without local anaesthetic. Cautery caused a transient rise in cortisol concentrations which returned to control values within 3 hours. The cortisol response to the scoop was more prolonged, as the plasma cortisol concentrations did not return to control levels until 7.5 hours after disbudding. The administration of a local anaesthetic reduced the cortisol response during the first 2 hours after scoop dehorning. This reduced response was followed by a delayed rise in cortisol concentrations between 2 and 7.5 hours. Cautery caused less distress than the scoop. The administration of local anaesthetic had little effect in alleviating distress in calves disbudded using the cautery iron.