Evaluation of propofol and medetomidine-ketamine for short-term immobilization of Gulf of Mexico sturgeon (Acipenser oxyrinchus de soti).

Parenteral anesthetic protocols for short-term immobilization were evaluated in twenty 4-yr-old Gulf of Mexico sturgeon (Acipenser oxyrinchus de soti). An initial dose-response trial determined the efficacy of either propofol (3.5-7.5 mg/kg. i.v.) or combinations of medetomidine (0.03-0.07 mg/kg, i.m.)-ketamine (3-7 mg/kg, i.m.). A subsequent study evaluated the physiologic effects of propofol (6.5 mg/kg, i.v.)-induced anesthesia and anesthesia induced with a medetomidine (0.06 mg/kg, i.m.)-ketamine (6 mg/kg i.m.) combination. The effects of medetomidine were reversed at 30 min with atipamezole (0.30 mg/kg, i.m.). Both drug protocols provided adequate short-term immobilization for minor diagnostic procedures. Sturgeon receiving propofol were in a light plane of anesthesia within 5 min after drug administration, whereas only 30% of the medetomidine-ketamine group reached a light plane of anesthesia in the same time period. Both propofol and medetomidine-ketamine resulted in mild bradycardia and apparent respiratory depression, with propofol producing more profound effects. At the dosages used in this study, both propofol and the medetomidine-ketamine combination effectively induced a light plane of anesthesia. Induction times were shorter in the propofol group.