Abstract

Parenteral anesthetic protocols for short-term immobilization of the threatened Gulf of Mexico sturgeon (Acipenser oxyrinchus de soti) were evaluated. An initial dose response trial determined the efficacy of either propofol (3.5–7.5 mg/kg IV) or combinations of medetomidine/ketamine (0.03–0.07 mg/kg IM, 3–7 mg/kg IM). A subsequent experiment evaluated the physiologic effects of both propofol (6.5 mg/kg IV) and a medetomidine/ketamine combination (6 mg/kg IM, 0.06 mg/kg IM) that were determined in the previous trial to be effective. The medetomidine was reversed at 30 min with atipamezole (0.30 mg/kg). Both drug protocols provided adequate short-term immobilization for minor diagnostic procedures. Sturgeon administered propofol reached light anesthesia within 5 min, while only 70% of the medetomidine/ketamine group reached light anesthesia in the same time period. Both propofol and medetomidine/ketamine produce mild bradycardia and apparent respiratory depression, with propofol producing more profound effects. In conclusion, both propofol and a medetomidine/ketamine combination produce adequate depth and length of sedation with propofol having a faster induction time.