Effects of hot-iron disbudding, using regional anaesthesia with and without carprofen, on cortisol and behaviour of calves.

The objective of this study was to assess cortisol and behaviour changes in calves hot-iron disbudded after different analgesic protocols. We assessed the response of 27 calves at 1, 3, 6 and 24 h after disbudding with regional anaesthesia (DA), regional anaesthesia plus carprofen (DAC), disbudded only (D) or sham-disbudded (ND). At 1h cortisol was higher in D compared with all other groups. At 3h DA showed higher cortisol than ND but did not differ from baseline. At 15 min and 1h pain-related behaviours were more frequent in the D group than in all other groups. Group D (3 h) and DA (3 and 6 h) showed more ear flicks and head rubs compared with DAC and ND. We concluded that head rubbing, head shaking and ear flicking are useful behaviours for evaluating pain after hot-iron disbudding. Disbudding causes severe pain in calves and only the association of regional anaesthesia with carprofen assures good welfare for 24 h.