IMMOBILIZATION OF WAPITI WITH CARFENTANIL AND XYLAZINE AND OPIOID ANTAGONISM WITH DIPRENORPHINE, NALOXONE, AND NALTREXONE

One hundred thirty-two wapiti (North American elk, Cervus elaphus) immobilizations were carried out with a mixture of carfentanil (3.7 +/- 1.33-mu-g/kg [mean +/- SD] and xylazine (0.14 +/- 0.08 mg/kg). All immobilizations were carried out with a blowdart aimed at the heavy muscles of the hind limb or shoulder. Fifteen animals received suboptimal injections over other areas of the body. Two of these animals required additional doses of drug before becoming immobilized, and the data on these animals have been excluded from the analyses. The mean time to recumbency for those animals that received injections into heavy muscles was 4.9 +/- 2.26 min. For those that were injected elsewhere, the time was 14.8 +/- 6.97 min. These times were significantly different. Narcotic antagonists used were naloxone, naloxone plus M5050, and naltrexone. The three antagonist regimes were compared, and no differences were evident in arousal times even between i.v. and i.m. routes of administration.