EVALUATION OF A BUTORPHANOL-MEDETOMIDINE REVERSIBLE ANESTHETIC PROTOCOL FOR MANED WOLVES (CHRYSOCYON BRACHYURUS ) UNDER MANAGED CARE.

Abstract

This study identified a safe, reversible protocol for maned wolves (Chrysocyon brachyurus). Over 15 anesthetic events, 11 healthy adult maned wolves (four females, seven males; ages 4.1-9.9 years; weights 24.3-28 kg) were anesthetized with medetomidine (target 0.05 mg/kg, range 0.049-0.052 mg/kg) and butorphanol (target 0.5 mg/kg, range 0.49-0.52 mg/kg) administered intramuscularly in a restraint device. At 40 ± 6 min after drug administration, the reversals atipamezole (5 mg per mg of medetomidine) and naltrexone (2 mg per mg of butorphanol) were administered intramuscularly. Inductions were rapid and smooth, median time to recumbency was five min (range 3-7 min), and safe handling was achieved at a median of nine min (range 7-18 min). Anesthetic depth in 14/15 anesthetic events was sufficient for physical examination, vaccine administration, blood collection, and urinary catheterization. One wolf demonstrated lighter sedation that did not allow more invasive procedures (urinary catheterization) but was sufficiently sedated for blood collection and physical examination. Heart rate, respiratory rate, peripheral oxygen saturation, rectal temperature, and indirect BP measurements were taken at 5-minute intervals. Bradycardia and hypoxemia were the most notable changes noted with this protocol but did not require medical intervention. Throughout anesthesia, all monitoring values remained stable, excluding rectal temperature which was seen to significantly decrease during this protocol. Venous blood gas evaluations at initial handling and immediately prior to reversal administration showed no significant changes during anesthesia. A single individual demonstrated a self-resolving ventricular tachycardia event of unknown origin. The only post-anesthetic complication was a single incidence of vomiting at recovery. Recoveries in all animals were smooth and rapid with a median time to standing of 11 minutes. A combination of medetomidine (0.05 mg/kg) and butorphanol (0.5 mg/kg) is expected to provide safe, smooth, reversible handling in maned wolves. These agents should be suitable for use for both minor procedures and sample collections.