Effects of 2‐phenoxyethanol anaesthesia on juvenile meagre (Argyrosomus regius)

Summary This study was performed to evaluate the effective concentration of the anaesthetic 2-phenoxyethanol (2-PE) on juvenile (1.3 ± 0.03 g) meagre (Argyrosomus regius, Asso, 1801) and establish the LC50 (through a series of exposure concentrations) and LT50 of 2-PE at 20 ± 0.5°C, salinity 38 g × L−1, pH 8.2–8.4 and dissolved oxygen >7 mg × L−1. The induction time decreased and the recovery time increased with increasing concentrations. Conflicting results were found only in recovery time and there were no significant differences among the recovery times from all concentrations. The most suitable concentration of 2-PE was 0.3 ml × L−1 for about or over 15 min exposure time. The LC50 and LT50 for the 3–60 min exposure periods were estimated for juvenile meagre. The toxic effect of 2-PE on survival rates of A. regius juveniles increased depending on the exposure period. In addition, 2-phenoxyethanol LT50 (median survival time) values, slope function (S) and lower and upper 95% confidence limits were estimated.