Physiological and behavioural alterations in disbudded goat kids with and without local anaesthesia

The physiological and behavioural responses were evaluated in goat kids that were disbudded either with or without local anaesthesia, in a study with 56 animals randomly allocated among five groups. The anaesthesia/disbudding group (AD, n = 12) was treated with 2 mL 2% lidocaine (L2%) around each horn bud, 20 min before disbudding by thermal cauterisation; kids in the anaesthesia group (A, n = 11) were treated as AD, without being disbudded; the saline/disbudding group (SD, n = 11) was treated with 2 mL saline and disbudded; the S group (n = 11) experienced only simulated disbudding; and control/disbudding kids (CD, n = 11) were disbudded without any treatment. Cortisol concentrations, heart rate (HR) and respiratory rate (RR) were determined from 20 min before to 4 h after disbudding. Struggles and vocalisations were also recorded during the procedure. Disbudding caused an acute and significant increase in cortisol concentrations and the values remained high for 2 h. Cortisol concentrations were higher in the disbudded groups (P < 0.05), even when local anaesthesia was used. HR and RR were not affected by treatment (P > 0.05). Frequency of struggles (10.5 ± 0.6, 10 ± 0.7, 12.8 ± 0.7 for AD, SD, and CD, respectively) and vocalisations (16.5 ± 1.2, 16.5 ± 1.3, and 19.3 ± 1.3 for AD, SD, and CD, respectively) were higher in disbudded kids than in the S group (5.6 ± 0.7 and 8.7 ± 1.3, for struggles and vocalisations respectively; P < 0.05). A greater percentage of kids showed high intensity behaviours in the disbudded groups (struggles: 83%, 72%, and 100% and vocalisations: 83%, 81%, and 100% for AD, SD, and CD, respectively) than in the S group (13% and 9%; P < 0.05). In conclusion, disbudding by thermal cauterisation induces an acute cortisol elevation and increases the expression of behaviours that indicate stress and pain. Infiltrating 2% lidocaine around each horn bud did not inhibit these responses.