Eugenol as an anesthetic for juvenile common snook

Abstract

The objective of this work was to evaluate the efficacy of eugenol as an anesthetic for juvenile common snook, and to determine the minimum effective concentration for use in handling procedures. In the first trial, juvenile common snook were subjected to immersion baths at 25, 50, 75, 100, 125, and 150 mg L^-1 eugenol concentrations, after which induction and recovery times were evaluated. In the second experiment, the lethal exposure time (LT50) at 75 mg L^-1 was estimated. Minimum effective eugenol concentration was 50 mg L^-1, and the stage of deep anesthesia and recovery were, respectively, reached at 126.3 and 208.8 s. At 75 mg L^-1, LT50 was 1,314 s, and induction time and recovery were also satisfactory; however, fish cannot tolerate over 229 s exposure.