Japan's Miyagi Prefecture said Friday a Japanese Black wagyu calf, conceived with freeze-dried semen, had been born in a breakthrough expected to lead the way to stably storing genetic resources of the premium beef.

According to the northeastern prefecture, it is the first instance in the world that a calf has been born after being conceived with freeze-dried semen.

(Wagyu calf born after conception with freeze-dried semen.)[Courtesy of the Miyagi prefectural government]

The female calf weighed 30 kilograms when it was born Tuesday in a Miyagi dairy farm in a joint project with Kochi University. The calf is in good health, prefectural officials said.

The calf was conceived with freeze-dried semen that had been in frozen storage at a temperature of minus 30 C.

The prefecture hopes to eventually rear calves conceived with semen stored at room temperature, the officials said.

Kazutsugu Matsukawa, an associate professor of livestock reproductive science at the university in western Japan, freeze-dried semen from a Shigefukuhisa bull in January 2019 that was then used to fertilize a cow in the Miyagi farm in July.

Usually, bovine semen is frozen in liquid nitrogen at a temperature of minus 196 C. If a natural disaster or other contingencies make it impossible to refill liquid nitrogen, the genetic resources can be lost.

Japan's beef exports including wagyu soared more than sevenfold to 24.7 billion yen ($230 million) in 2018 from 3.4 billion yen in 2010 amid growing wagyu popularity overseas.