EXPERIMENTAL TECHNIQUES
Since experimental procedures have the potential for injuring the fish - experience becomes the best teacher. Techniques that are new to the operator should be learned from an experienced operator and practiced under supervision.
Some procedures require manipulations to the fish outside the tank and anesthetizing the fish becomes necessary. The most common anesthetic used is tricaine methanesulfonate or MS-222 in an aqueous solution. A stock solution is previously made and diluted to deliver an anesthetic dose of 100 - 200 mg/l. As the fish is anesthetized its respirations will become slower, the fish will list to one side, become disoriented and finally will lie on its side. At this point the fish is anesthetized adequately for short procedures. The fish should be returned to a fresh water tank as soon as possible.
A fish listing to one side as anesthesia is induced