Comparative Efficacy of Three Anesthetic Agents on Juvenile African Catfish, Clarias gariepinus (Burchell, 1822)

In this study, the efficacy of three anaesthetic agents (clove oil, 2-phenoxyethanol and eugenol) was compared in captive-bred African catfish, Clarias gariepinus (Burchell, 1822). The lowest effective concentrations based on the efficacy criteria of complete anesthesia induction within 180 s and recovery within 300 s were determined to be 50 mg L-1 (induction 193 +/- 62 s and recovery time 251 +/- 32 s) for clove oil, 750 mu l L-1 (induction 145 +/- 24 s and recovery time 174 +/- 10 s) for 2-phenooxyethanol, and 50 mg L-1 (induction 197 +/- 29 s and recovery time 310 +/- 17 s) for eugenol. The onset of individual phases of anesthesia and recovery times depended significantly on the concentration of the anaesthetic used (P<0.05). An inverse exponential relationship was observed between concentrations of anaesthetic and induction time, whereas exponential relationships were observed between concentrations and recovery times for all anaesthetic agents evaluated. The final conclusion of this study, clove oil is the most suitable agent for juvenile African catfish from the three anesthetics tested.