The utility of a novel formulation of alfaxalone in a remote delivery system

Abstract

ObjectiveTo quantify induction time, reliability, physiological effects, recovery quality and dart volume of a novel formulation of alfaxalone (40 mg mL−1) used in combination with medetomidine and azaperone for the capture and handling of wild bighorn sheep. Study designProspective clinical study. AnimalsA total of 23 wild bighorn sheep (Ovis canadensis) in Sheep River Provincial Park, AB, Canada. MethodsFree-ranging bighorn sheep were immobilized using medetomidine, azaperone and alfaxalone delivered with a remote delivery system. Arterial blood was collected for measurement of blood gases, physiologic variables (temperature, heart and respiratory rates) were recorded and induction and recovery length and quality were scored. ResultsData from 20 animals were included. Administered dose rates were alfaxalone (0.99 ± 0.20 mg kg−1; 40 mg mL−1), azaperone (0.2 ± 0.04 mg kg−1; 10 mg mL−1) and medetomidine (0.16 ± 0.03 mg kg−1; 30 mg mL−1). The mean drug volume injected was 1.51 mL. The median (range) induction time was 7.7 (5.8–9.7) minutes, and recovery was qualitatively smooth. Conclusions and clinical relevanceAn increased concentration formulation of alfaxalone was administered in combination with medetomidine and azaperone, and resulted in appropriate anesthesia for the capture and handling of bighorn sheep. The dart volume was small, with potential for reducing capture-related morbidity.