FISHERIES RESEARCH INSTITUTE,MOA,TAIWAN

Responses of goldlined sea bream (Sparus sarba) to the anesthetic 2-phenoxyethanol were investigated. We found that induction time (INT) and recovery time (RET) increased when anesthesia reached to the later stages. INT increased also with lower concentration of 2-PE, while RET had opposite phenomenon. However, larger fish took longer INT, but RET did not show the other way. Different intervals between two anesthesias resulted different INT (INT2) of the second anesthesia in comparison with that of the first INT (INT1). at 0 or 5 minutes of interval, INT2 was shorter than INT1. As opposite to the above findings, INT2 was longer than INT1 at 30 minutes, 1 hour or 6 hours of interval. At 24 hours of interval, half of the anesthetized fish had longer INT2 and the rest of fish had shorter INT2. The results indicated that the anesthetic sensitivity of goldlined sea bream responded to 2-PE would revert after 24 hour's recovery from first anesthesia.