Effect of Spearmint (/-Carvon) Oil and Methyl Salicylate Oil Emulsion on Anesthesia of Rutilus frisii kutum

Anesthetics are used with increasing frequency in aquaculture, mainly to reduce the stress and to prevent mechanical damage to fish during handling. Present study is the first study on the effect of spearmint (/-carvone) and methyl salicylate oil emulsion (CMSE) on anesthesia of Rutilus frisii kutum with average body weights 3.35±0.25 g in Iran. The water temperature was 20 ˚C and pH was 8.1 during the investigation. Fish were exposed to the concentrations of 197, 263 and 395 µl/L of CMSE. Results showed that induction time decreased significantly with increasing of the concentration of CMSE (P0.05). Opercular rate firstly increased and then slowly decreased with increasing the concentration of anesthetic. Also, no mortality was observed in the study. The results of this study show that applications of spearmint and methyl salicylate oil emulsion in 263 µl/L level, can be suitable for anesthetization of Rutilus frisii kutum.