BERLIN (AP) – Scientists say they’re several steps closer to perfecting a method that could prevent the extinction of northern white rhinos, of which only two animals are known still to be alive.
According to a paper published Wednesday in the journal Nature Communications, researchers have succeeded in creating embryos using frozen northern white rhino sperm and eggs from a southern white rhino, a closely related sub-species.
It’s the first time such hybrid embryos have been created and the scientists from Germany, Italy and the Czech Republic say it could provide a pathway to saving the critically endangered northern white rhino after the last male, called Sudan, died in March.
They plan to harvest the egg cells of the two surviving female rhinos soon and use preserved sperm to produce “pure” northern white rhino embryos. Since the females, a mother and daughter called Najin and Fatu, are unable to bear offspring themselves, the embryos would be implanted in a southern white rhino surrogate.
In order to increase the supply of eggs and preserve the northern white rhino’s genetic diversity, scientists are also working on a second method that would coax frozen skin cells from deceased animals into becoming egg cells, a procedure that has already succeeded in mice.
Thomas Hildebrandt, of the Leibniz Institute for Zoo and Wildlife Research in Berlin, said researchers hope the first northern white rhino calf will be born in about three years.
