Effect of isoflurane alone or in combination with meloxicam on the behavior and physiology of goat kids following cautery disbudding

This study evaluated the effect of administering general anaesthesia (isoflurane) and/or a non-steroidal anti-inflammatory drug (meloxicam) on goat kid behavior and physiology following cautery disbudding. Trial one (n=12/treatment) evaluated behavior in 72 female Saanen dairy goat kids (5 ± 3 days old) and trial two (n=10/treatment) evaluated physiology in 60 female Saanen dairy goat kids (4 ± 2 days old). Goat kids were randomly assigned to one of six treatment groups that were disbudded given either: 1) no pain relief (CAUT), 2) oral meloxicam (0.2 mg/kg BW; O-MEL), 3) meloxicam s.c. (0.5 mg/kg BW; I-MEL), 4) isoflurane gas (ISO), 5) isoflurane and meloxicam s.c. combined (MEL+ISO), or 6) sham-handled only (simulated disbudding; SHAM). The frequency and duration of head shaking, head scratching, self-grooming, feeding and body shaking were continuously recorded for 24 h pre- and post-treatment. Lying behavior was recorded continuously for 24 h before and after treatment using accelerometers. Plasma cortisol, glucose and lactate concentrations were measured in blood samples collected immediately prior to treatment (baseline) and at 15 min, 1 and 2 h post-treatment. Body temperature was measured immediately after blood sampling at all blood sampling time points. Head shaking and body shaking frequencies were higher at 5 min post-treatment in CAUT than SHAM kids, and lower in MEL+ISO and ISO kids than CAUT kids (P ≤ 0.05). Head scratching durations at 1 h post-treatment were higher in CAUT than SHAM kids (P ≤ 0.05) and O-MEL were similar to SHAM kids from 2 h post-treatment (P > 0.24). Self-grooming and feeding frequency/duration and lying duration did not differ between groups (P > 0.92). Cortisol concentrations were higher (P = 0.04) in CAUT than SHAM kids and MEL+ISO and ISO had lower cortisol concentrations (P ≤ 0.05) than CAUT kids over the 2 h sampling period. Moreover, O-MEL kids had similar cortisol concentrations to CAUT kids (P = 0.86). Plasma glucose and lactate concentrations and body temperature were not affected by treatment (P > 0.28). In conclusion, the administration of isoflurane or meloxicam appeared to reduce the stress response to cautery disbudding, however the combined effects may provide greater relief.