A university team has succeeded in the first-ever mass proliferation of rainbow trout germ line stem cells (GSCs) in vitro, a technique that could pave the way for preservation of endangered fish and enable their mass production.

The team at Tokyo University of Marine Science and Technology spawned some 1,700 rainbow trout after producing sperm and eggs using GSCs from just one of its males, it wrote in the Monday edition of Communications Biology, a science magazine published by Nature Research.

"We can apply the methods within the next few years for conservation projects of Salmonidae similar to rainbow trout," said Goro Yoshizaki, a professor of marine biology and resources at the university who led the team.