Toshi's work

Sinking death syndrome during finfish larviculture Masatoshi FUTAGAWA / CORDUNAP June 30, 2012 Phenomenon Sinking death syndrome occur during early life stage of finfish larviculture, 3 to 7 days post hatch-out (DPH), that larvae settle on bottom at nighttime mostly and it makes mass mortality due to bacteria contamination and anoxia. Several species has the syndrome and that is one of the bottlenecks of mass production. I had the syndrome during the larviculture of Graus nigra , Pacific beakfish ( Oplegnathus insignis ), Japanese flounder ( Paralichthys olivaceus ) and Grater amberjack ( Seriola dumerili ). Causes Increasing body density Finfish larvae consume yolk and oil droplet few days after hatch-out and change body density. Usually, body density of larvae is heavier than water (1.0236±0.0001 at WT 25 ̊C). According to Teruya et al. 2008 , Greater amberjack larva shows it consume yolk and oil droplet until 4 DPH and body water contents reduce from 2 DPH (93.5...

Reduction of coastal fish resources is common problem in the whole world due to overfishing. Qn the other hand, demand is rising due to health consciousness (less cholesterol), contamination of chicken (influenza), cow (BSE) and pork (HEV). Marine ranching is the one of solution to recovering coastal fish resources which has operated in Japan more than four decades. The result shows that some fishes are recovered, even increased, and contribute benefits. Chile coast water has higher productivity compare to Japan and the method produce more fishes quickly. It may create new business model which has less energy consumption, no contamination and sustainable production, and create employment at rural area. 1.             What is Marine ranching 1.1.              Idea and activities General ideas of marine ranching are releasing fish juvenile dismissing species int...