Shin, Gee-wook;Shin, Yong-seung;Kim, Young-rim;Lee, Eun-young;Yang, Hyang-hee;Palaksha, K.J.;Huh, Nam-eung;Yeon, Seong-chan;Lee, Hee-chun;Oh, Myung-ju;Joh, Seong-joon;Kang, Seung-won;Jung, Tae-sung
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Olive flounder (Paralichthys olivaceus) is the major mariculture fish in Korea. The annual aquaculture production of olive flounder in Korea during the period of 2003 was 300,000 ton (2002 Statistics, Ministry of Maritime Affairs & Fisheries, Korea Government). Anesthetics is very necessary in aquaculture to minimize stress and damage during harvesting, grading, transportation, spawning induction and handling to fish. In the present study, isoeugenol as new anesthetic in marine fish, especially olive flounder, was examined to know the efficacy and proper concentration. As a result, olive flounder adult was exhibited sedation at 5 ppm at 10 and $15^{\circ}C$, and 7.5 ppm at $20^{\circ}C$, respectively. Anesthesia was required at least 10, 7.5 and 10 ppm at $10^{\circ}C$, $15^{\circ}C$ and at $20^{\circ}C$, respectively. In case of fry, the effect of sedation was observed from 2.5 ppm at $10^{\circ}C$ and 5 ppm at 15 and $20^{\circ}C$, respectively. Anesthesia was observed from 2.5 ppm at $10^{\circ}C$, 5 ppm at 15 and $20^{\circ}C$, respectively. In acute toxicity test, it was impossible to explore $LD_{50}$ with the concentration of isoeugenol adult at $15^{\circ}C$ used, but over immersion volume of 15 ppm at $15^{\circ}C$ was observed mortality in fry. Based on the present study, isoeugenol was identified as a safe and active anesthetic to olive flounder.