A company in Oita Prefecture said it has succeeded in the world’s first farming of bluefin tuna using only formulated feed.

Hyoshoku Co. said Wednesday that using the feed makes it easier to control the quality of the tuna regardless of the season.

The company will start selling the tuna locally before shipping it to other parts of the country.

Fish such as mackerel are typically used to raise bluefin tuna, but seasonal changes of nutrients and deterioration of water quality caused by leftover feed pose problems, Hyoshoku said.

The company added, however, that tuna raised on the formulated feed grow more slowly and production costs are higher.

KEYWORDS tuna, fishing