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Table 1 Stages of anesthesia with clove oil in fish (Keene et al., 1998, modified from McFarland, 1959; Jolly et al. 1972) and Stages of recovery from anesthesia in fish (Keene et al., 1998modified from Hikasa et al., 1986) in fish

From: Use of propofol as an anesthetic and its efficacy on some hematological values of ornamental fish Carassius auratus

Stage Behavior in anesthesia stages Behavior in recovery stages
1 Normal Reacts to external stimuli; opercular rate and muscle tone normal Decreased opercular movement
2 Light sedation Slight loss of reactivity to external visual and tactile stimuli; opercular rate slightly decreased; equilibrium normal Partial recovery of equilibrium; partial recovery of swimming motion
3 Deep sedation Total loss of reactivity to external stimuli except very strong pressure; Total recovery of equilibrium
4 slight decrease in opercular rate; equilibrium normal Partial loss Partial loss of muscle tone; increased opercular rate; reacts of equilibrium only to strong tactile and vibrational stimuli Reappearance of avoidance swimming motion; reaction to external stimuli; behavioral response still stolid
5 Total loss Total loss of muscle tone and equilibrium; slow but regular of equilibrium opercular rate; loss of spinal reflexes Swimming, rarely striking head firmly to sides or against bank of the tank
6 Loss of reflex Total loss of reactivity; opercular movements slow and reactivity irregular; heart rate very slow; loss of all reflexes Total behavioral recovery; normal swimming