Innovation of aquaculture system of fish in the coastal water of Miyagi Prefecture

Representative Organization: Tohoku University

2014/04/01 - 2015/03/31

Others(Innovation of Aquaculture System)

This study aims the innovation of novel aquaculture system of salmonid fish. We are investigating the effects of specific light wavelengths on the somatic growth and metabolism of rainbow trout.

We have examined the effects of lighting condition on the growth and physiological condition in rainbow trout. 1. After exposure of green or red LED light to triploid trout in outdoor tank for 33 days, the red light group showed higher growth than the green light group and higher condition factor (ponderal index) than the control group (under ambient light without any LED light). These results suggest that red light might have growth promoting effect on triploid trout. 2. Diploid trout were kept in 2 tanks colored black and 2 tanks colored white for 15 days. The fish were fed in one tank but not fed in another tank for each tank color condition. After that, we measured mRNA levels of growth hormone (GH) gene in the pituitary, melanin-concentrating hormone (MCH) gene in the brain, and of hormone-sensitive lipase (HSL) gene in the liver. The fed fish in white tank showed higher mRNA levels of GH and MCH than fed fish in black tank. The unfed fish in black tank showed higher mRNA levels of HSL than unfed fish in white tank. These results suggest that background color might influence the energy metabolism in trout, and that GH, MCH, or HSL might be involved in that effect.

FY2014 Innovation of aquaculture system of fish in the coastal water of Miyagi Prefecture