Yohimbine Reversal of Ketamine-Xylazine Immobilization of Raccoons (Procyon Lotor)

Abstract

Six adult raccoons (Procyon lotor) were sedated with a combination of ketamine hydrochloride (KH) at 10 mg/kg body weight and xylazine hydrochloride (XH) at 2 mg/kg body weight intramuscularly (i.m.). Twenty min after the KH-XH combination was given, yohimbine hydrochloride (YH) at either 0.1 mg/kg (Trial 1) or 0.2 mg/kg (Trial 2) body weight or a saline control (Trial 3) was administered intravenously (i.v.). The time to arousal, time to sternal recumbency and time to walking were recorded. These times were significantly shortened after YH administration [e.g., mean time to walking (MTW) at 0.2 mg/kg YH = 23.7 min] as compared to the saline controls (MTW = 108.8 min). Heart and respiratory rates both increased after YH administration, while body temperature remained constant. A fourth trial was performed using a higher ratio of KH to XH (45:1 rather than 5:1) to mimic sedation as performed in the field. The mean time to arousal (MTA) and MTW in this trial (1.3 and 23.7 min, respectively) were significantly shorter than controls and similar to YH trials performed after immobilization with 5:1 KH-XH. Yohimbine hydrochloride may be useful in field studies that require sedation of raccoons using KH-XH combinations.

Field immobilization of raccoons with ketamine hydrochloride and xylazine hydrochloride

“…Because of confounding results of multiple injections, data from the 3 raccoons that received 1 dose were not summarized. Induction and recovery times (n = 8) were similar to induction and walking times reported for captive raccoons immobilized with a 5:1 mixture of K H /XH at approximately 2 5 -5 0 % of the total drug amount used in this study (Deresienski and Rupprecht 1989). Additionally, heart rate was almost identical to values reported by Deresienski and Rupprecht (1989) for captive raccoons.…”

Mucosal Adjuvants to Improve Wildlife Rabies Vaccination

“…Raccoons were housed individually in 33332.5-m pens that included den boxes and enrichment structures at the US Department of Agriculture National Wildlife Research Center's Outdoor Animal Research Facility (Fort Collins, Colorado, USA) for the duration of the study. Prior to the experiment, raccoons were evaluated for health after intramuscular administration with 10 mg/ kg ketamine HCl and 2 mg/kg xylazine (Deresienski and Rupprecht, 1989). IvomecH (0.1 mL/5kg, per os, Merial) was also administered to raccoons to control internal parasites, and raccoons were vaccinated for distemper with the GAL-AXY DH vaccine (Schering-Plough Animal Health Corporation, Boxmeer, The Netherlands) and microchipped (Avid Identification Systems, Inc., Norco, California, USA).…”

Efficacy of Zoletil® for Field Immobilization of Raccoons

“…Other studies of raccoons used phencyclidine hydrochloride as an immobilizing agent (Fritzell 1978, Greenwood 1982, but Bigler and Hoff (1974) had qualitative evidence suggesting that phencyclidine recovery times were particularly long and recommended a switch to ketamine. Ketamine and combinations of ketamine and xylazine have provided suitable immobilization of raccoons (Deresienski andRupprecht 1989, Belant 1995); however, some studies have noted muscle spasms and vomiting (6/18 raccoons) directly after induction (Deresienski and Rupprecht 1989). Raccoons also were reported to experience nasal discharge, hypersalivation, and minor muscle spasms prior to arousal (Belant 1995).…”