Immobilizing and handling large, free-ranging animals without proper facilities in harsh environmental conditions poses significant challenges. During two field expeditions, a total of 29 female muskoxen ( Ovibos moschatus) were immobilized in Northeast Greenland (74°N, 20°E). Fixed doses of immobilizing drugs were used regardless of animal size: 2 mg etorphine, 30 mg xylazine, 0.3 mg medetomidine, and 40 mg ketamine. Physiologic and behavioral monitoring was performed during the second expedition on 15 female muskoxen. The observed heart rates were 35-58 beats/min and respiratory rates were 25-30 breaths/min. Mean arterial pressures measured using oscillometry ranged between 117-142 mmHg. Pulse oximeter readings ranged from 91-98% with oxygen supplementation, nasal end-tidal carbon dioxide values were 24-42 mmHg, and rectal temperature ranged from 38.9-39.6°C. Induction time was 6-8 min, recovery time 2-6 min after reversal, and duration of anesthesia was 50-100 min. This anesthetic regime thus provided reliable immobilization with minimal pathophysiologic alterations.
Keywords: Anesthesia; etorphine; ketamine; medetomidine; muskox (); xylazine.