Artificially inseminated eel spawn growing well

The Yomiuri Shimbun

Some of the first eels in the world to be fully cultivated from sperm and eggs collected from artificially raised parents have successfully grown to juveniles, the Fisheries Research Agency has announced.

In March, eggs and sperm were taken from adult eels that had been spawned via artificial insemination at a fish farming center run by the agency in Shibushi, Kagoshima Prefecture. The eggs were artificially fertilized with the sperm, and several days later, baby eels hatched from the fertilized eggs.

Currently, researchers are raising about 1,000 infant eels, called shigyo. Of these, about 30 had grown into juveniles--called shirasu-unagi--by the end of last month, the agency said.

Shirasu-unagi are smaller than full-grown eel, but have developed adult body features.

The smooth growth of the shigyo spawned from entirely cultured eels indicates the great progress that has been made in efforts to mass-produce eel for commercial purposes, according to the Yokohama-based research center.