A comparative study of xylazine-induced mechanical hypoalgesia in donkeys and horses

Abstract

Objective To compare the effects of xylazine on mechanical nociceptive thresholds in donkeys and horses. Study design Randomized, controlled, crossover, Latin-square, operator-blinded design. Animals Six 3.1±0.89year old standard donkeys weighing 145.0±30.5kg and six 9.6±4.4year old Thoroughbred horses weighing 456.0±69.0kg. Methods Each animal received one of four doses of xylazine (0.5, 0.7, 0.9, and 1.1mgkg-1), or acepromazine (0.05mgkg-1) or saline solution (0.9%) intravenously and mechanical nociceptive thresholds were assessed over 90minutes. The areas under the threshold change versus time curve values for 60minutes (AUC0-60) post-drug administration were used to compare the effect of..