Saving the northern white rhino with IVF

Some grounds for cautious optimism, via Andres Soolo.

The seemingly "disastrous" story of the world's most endangered mammal - the northern white rhino - could be rewritten by IVF, scientists claim.They used the method to produce rhino embryos with sperm from two dead males. The embryos were made using eggs from a closely related sub-species, but the scientists say the method could save the northern white rhino.

One of the team said he hoped a baby that's fully northern white rhino would be born "within three years". This could provide a way of "rescuing valuable genes" from a sub-species that is already functionally extinct; the last male northern white rhino, named Sudan, died earlier this year at the age of 45.

Only two females now remain, but the researchers who carried out this project say their carefully-developed method of assisted reproduction could work with eggs harvested from those two precious animals.

But Dr Terri Roth, from Cincinnati Zoo, said the team's suggestion that they would have a "new baby on the ground" within three years was "optimistic". "Embryo transfer [into a surrogate mother] in rhinos is in its infancy and has not yet been successful in any rhino species," Dr Roth told BBC News. "And there are just two female northern white rhinos alive today, so acquiring white rhino [eggs] will be challenging and their number will be limited. Any embryos produced would likely need to be cryopreserved (or frozen) until a surrogate could be set up."

https://www.bbc.co.uk/news/science-environment-44687544