Abstract:
Goats are rarely anaesthetised; consequently, scant information is available on the efficacy of
anaesthetic drugs in this species. Alfaxalone is a relatively new anaesthetic agent, of which
the efficacy in goats has not yet been studied. In this study, the sedative and alfaxalonesparing
effects of midazolam and butorphanol, administered alone or concomitantly, in goats
were assessed. Eight clinically healthy goats, four does and four wethers, were enlisted in
a randomised crossover manner to receive intramuscular sedative treatments consisting of
saline 0.05 mL/kg, or midazolam 0.30 mg/kg, or butorphanol 0.10 mg/kg, or a combination of
midazolam 0.30 mg/kg with butorphanol 0.10 mg/kg before intravenous induction of general
anaesthesia with alfaxalone. Following induction, the goats were immediately intubated and
the quality of anaesthesia and basic physiological cardiorespiratory and blood-gas parameters
were assessed until the goats had recovered from anaesthesia. The degree of sedation, quality
of induction and recovery were scored. When compared with saline (3.00 mg/kg), midazolam,
administered alone or with butorphanol, caused a statistically significant increased level of
sedation and a reduction in the amount of alfaxalone required for induction (2.00 mg/kg and
1.70 mg/kg, respectively). Butorphanol alone (2.30 mg/kg) did not cause significant changes
in level of sedation or alfaxalone-induction dose. During induction and recovery, the goats
were calm following all treatments, including the control group. Cardiorespiratory and bloodgas
parameters were maintained within clinically acceptable limits. The present study showed
that midazolam, administered alone or combined with butorphanol, produces a degree of
sedation that significantly reduces the dose of alfaxalone required for induction of general
anaesthesia in goats, without causing any major adverse cardiorespiratory effects.
