PHYSIOLOGICAL-EFFECTS OF MEDETOMIDINE-ZOLAZEPAM-TILETAMINE IMMOBILIZATION IN BLACK BEARS

A combination of medetomidine-zolazepam-tiletamine (MZT) was used to i mmobilize four black bears (Ursus americanus). The drugs were used at a dose of approximately 52 mu g/kg of medetomidine, 0.86 mg/kg of zola zepam, and 0.86 mg/kg of tiletamine. Induction occurred in 6.3 +/- 3.3 min (mean +/- SD). The combination produced minimal adverse cardiopul monary effects. Hypertension occured in all four bears. Oxygenation an d ventilation was good in three of the four bears. One bear demonstrat ed slight hypoxemia and hypoventilation at 15 min following drug admin istration. At one 1hr following drug administration atipamezole was ad ministered at a dose of approximately 240 mu g/kg. Recovery time was t aken as the time from administration of the atipamezole until the time that the bear was sitting in the trap. Recovery occurred in 6.0 +/- 4 .1 min. MZT produced rapid, reliable immobilization in black bears wit h minimal adverse physiological effects. Immobilization, produced by t his combination, was readily reversible with atipamezole.