Press Release

May 23 , 2014

Fisheries Research Agency

The first spawn-taking from bluefin tuna broodstock in large-scale tanks: First step toward stable seed production of artificial juveniles for aquaculture

In June 2013, the Fisheries Research Agency (FRA) commenced the technical development for egg collection from reared broodstock of Pacific bluefin tuna under the controlled environmental conditions (water temperature and day length) at a tuna research facility at the Seikai National Fisheries Research Institute in Nagasaki Prefecture. This was proposed in order to establish a system for collecting eggs from bluefin tunas broodstock reared in large-scale spawning tanks under controlled conditions. On May 16, 2014, we reported for the first time, the successful spawning of broodstock bluefin tuna reared in our large-scale tanks, and collection of the fertilized eggs.

Traditionally, in Japan, egg collection from reared broodstock bluefin tuna have been carried out in a net cage in the sea at some facilities, including those of the FRA. However, because environmental conditions such as water temperature vary depending on the conditions around sea area and year, inconsistent data on the development of fish and egg collection are available. Therefore, using a facility at which environmental conditions can be controlled (which was constructed using the facility development subsidy granted by the Fisheries Agency), we are developing a technology for the stable egg collection from the broodstock reared in a controlled environment. This project has been commissioned by the Agriculture, Forestry and Fisheries Research Council.

Bluefin tunas broodstock (3 years old) in a
large-scale spawning tank
(mean body weight estimated, 28 kg)
Newly hatched larvae
(mean total length, 3.25 mm)