Thomas D. Williams, DVM; John Christiansen; Scott Nygren
Chemical immobilization of teliosts and elasmobranchs allows manipulation
when physical restraint is not possible or advisable. In large exhibit tanks intramuscular
anesthesia is advantageous to reduce trauma, capture and transportation stress in fast moving
fish and large specimens. K in doses of 30 to 40 mg/lb was found to be a safe, short acting,
easily administered, intramuscular immobilizing agent for fish. In over 50 trials, fish
anesthetized with the recommended dose exhibited no serious side effects. No deleterious effects
occurred except at dosages above 98 mg/lb. Demitomidine at a dose of-50-l00 ugm/kg when combined
with ketamine at 1-2 mg/kg was given intramuscularly and was reversible with antipamizole at a
dose of 200 ugm/kg.
Ketamine hydrochloride and ketamine/demitomidine are compared to azaperone,
carfentanyl, diazepam, fentanyl, metomidate, MS-222, Norcuron (vecuronium bromide), saffan
(alphaxalone-alphadolone), succinyl choline, telazol (tiletamine-zolazepam), tracium (atracurium
beslate), versed, xylazine and yohimbine. 358 trials were done using 21 individual drugs or drug
combinations.
The species of temperate water fishes which were administered intramuscular
anesthesia were stripped bass (Morone saxattilis), rockfish (Sebastes sp.),
Pacific mackerel (Scomber japonica), white sturgeon (Acipenser transmontanus),
rainbow trout (Salmo gairdnerii), giant sea bass (Stereolepis gigas),
Sheephead (Semicossyphus pulcher), leopard sharks (Triakis semifasciata) and spiny
dogfish (Squalus acanthias).