Researchers at the University of Minnesota have made a breakthrough in the cryopreservation of fish, which could help preserve species and repopulate the ocean.

Researchers at the University of Minnesota have made a breakthrough in the cryopreservation of fish, which could help preserve species and repopulate the ocean.

Researchers are using gold nanoparticles and lasers to freeze and thaw live fish embryos, the Minnesota Daily (http://bit.ly/2vujl0k) reported.

Researchers have previously been able to successfully cryopreserve mammal embryos and some animal sperm, but have been unable to do the same to fish embryos.

The key is being able to warm an embryo quickly enough so no ice crystals form, said Kanav Khosla, a Ph.D. student in the university's department of mechanical engineering.

"The ability to freeze (fish) down is like an insurance policy . Even if all of them died, you have them somewhere . and you can use it for research (or) for repopulating the oceans," he said.

Mary Hagedorn, a marine biologist at the Smithsonian Conservation Biology Institute, said she hopes the findings will help advance research, species conservation and food production.

Researchers typically use zebra fish to genetically modify fish and study human diseases, and freezing the fish could speed up the process, she said.

It may also allow farmers to raise fish year round instead of just during spawning season, she said.

The research team hopes to apply their breakthrough toward conserving reptiles, amphibians, birds and other fish.

"Frogs, for instance, are dying around the world and we cannot cryopreserve frog embryos, but with this new technology, we will be able to," Hagedorn said.

They're also looking into applying the method to coral preservation, Khosla said.

"We've lost almost a thousand kilometers of the Great Barrier Reef and if you had frozen embryos from many of those species," Hagedorn said, "you could basically just thaw them out and get them started."