Scientists in Europe have created the first-ever hybrid rhino embryo produced outside the womb, a major breakthrough in the race to save the northern White rhino from extinction. The next step will need to take the eggs of the two last females of the Northern white Rhino and create a clean embryos of the Northern white Rhino.
Najin (L) and Fatu are the only two northern white rhino known to be alive today - both are infertile females.
According to Ol Pejeta, the embryo has a strong chance of surviving to term and thus producing other northern white rhinos.
The southern white rhinoceros is a subspecies of the white rhino and its population is now rated as "near threatened" by the IUCN Red List of Threatened Species, with about 21,000 individuals remaining. "Now we are well prepared to go to Kenya and collect [eggs] from the last two [northern white rhino] females in order to produce pure [early embryos] where both eggs and sperm are from [northern white rhino]", Hildebrandt said.
The only hope for the northern white rhino is to join that list.
In a paper published to Nature Communications, Prof Thomas Hildebrandt from the Leibniz Institute for Zoo and Wildlife Research in Berlin and a team of global researchers revealed they had recovered sperm from two dead male rhinos. Better still, the embryos give researchers a source of stem cells, which could be turned into better quality sperm and eggs.
In the meantime, the team will practice, implanting some of their hybrid embryos into SWR surrogates "to test the system". It struck a awful blow for the species, who were then functionally extinct.
Northern white rhinos were driven to extinction by poaching and war in the countries they once roamed - Chad, Sudan, Uganda, Congo and Central African Republic.
"We are quite confident with the technology we have developed", he said during a telephone conference with reporters detailing the research.
These achievements raise the possibility that a hybrid rhino, which preserves numerous genes of the northern white rhino, could be bred in future.
"The concern in the conservation community is that people will hear this and think, 'We can save the rhinos with science and then become more complacent about the other strategies we have in action now, ' " Roth said.
As for the female eggs, they were taken from the southern white rhinoceros from several European zoo parks, including the Dvur Kralove Zoo. The embryonic stem cell lines obtained in this study have now been transferred to Dr Diecke's lab, as they will serve as a blueprint to differentiate iPS cells into germ cells and eventually gametes.
Historical distributions of the northern (red) and southern (green) white rhino. As scientists hope samples of tissues of such animals will help a modern or future environmentalists to revive these species and restore their populations.
But they've already got a plan for developing that diversity.
Professor Cesare Galli, whose team generated the rhino stem cells, said: 'Pluripotent stem cells have the ability to self-renew indefinitely and to develop into any cell of a living organism'.
"We should be working on all fronts", Roth said.