Evaluation of alternatives to cautery disbudding of dairy goat kids using behavioural measures of post-treatment pain

Abstract

Alternatives to cautery disbudding (caustic paste and cryosurgical disbudding, and clove oil injection) were evaluated using behavioural measures of post-treatment pain in dairy goat kids. Fifty Saanen doe kids were randomly assigned to one of five treatments (n = 10/treatment): (i) cautery (CAUT), (ii) caustic paste (CASP), (iii) cryosurgical (liquid nitrogen; CRYO), (iv) clove oil (CLOV) or (v) sham disbudding (SHAM). Head and body shaking, head scratching, self-grooming and feeding were video-recorded for 24 h pre- and post-treatment. Frequencies of each behaviour were measured over 1 h pre- and post-treatment, as were the durations of head scratching, self-grooming and feeding. Accelerometers measured lying bouts and lying time for 24 h pre- and post-treatment. CASP kids displayed more head shakes (73.7 vs. 38.5 ± 11.06 No./h) and head scratches (35.1 vs. 13.1 ± 6.62 No./h) but less self-grooming (1.3 vs. 10.8 ± 2.00 No./h) and body shakes (1.6 vs. 4.3 ± 0.88 No./h), and shorter feeding durations (1.0 vs. 2.4 ± 0.61 min/h), than CAUT kids (P ≤ 0.05). CRYO kids performed more head scratches (28.8 vs. 13.1 ± 6.62 No./h) but less body shakes (2.1 vs. 4.3 ± 0.88 No./h), and spent less time lying (15.8 vs. 17.0 ± 0.32 h/24 h) but with more bouts (32.8 vs. 26.3 ± 2.25 No./24 h) than CAUT kids (P ≤ 0.05). Head shaking, scratching and self-grooming frequencies in CLOV kids (34.0 ± 11.06, 16.7 ± 6.62 and 12.6 ± 2.00 No./h, respectively) were no different to those for CAUT kids (P > 0.10). CLOV kids spent less time lying (16.1 vs. 17.0 ± 0.32 h/24 h) (but with more bouts [33.4 vs. 26.3 ± 2.25 No./24 h]) than CAUT kids (P ≤ 0.05), which suggests less pain, as SHAM kids spent less time lying than CAUT kids (16.2 vs. 17.0 ± 0.32 h/24 h; P ≤ 0.05). Our results suggest that caustic paste and cryosurgical disbudding were more painful than cautery disbudding and may not be suitable alternatives for goat kids. During the first hour after treatment, clove oil injection appeared to cause less pain than caustic paste or cryosurgical disbudding, but a similar behavioural response as cautery disbudding. Clove oil injection may show promise as an alternative to cautery disbudding. However, future research should first evaluate the efficacy clove oil in preventing horn growth; if effective, further research on the long-term effects of clove oil on goat welfare should be conducted.