IVF could be the answer to conserving the genes of the world's most endangered mammal, the northern white rhino, according to a new international scientific journal.
Only two infertile female northern white rhinos are left in the world the daughter and granddaughter of the last surviving male northern white rhino, named Sudan, which died earlier this year.
So scientists have used in vitro fertilisation to create embryos, the article in Nature Communications states. It is first documented generation of blastocyst, or pre-implantation rhino embryos, using IVF procedures that had never been previously tried with the species.
Researchers used frozen sperm from male northern white rhinos - now deceased - to fertilise eggs from female southern white rhinos, a closely related sub-species, before freezing the embryos in the hope of planting them in a surrogate female southern white rhino.
The paper states how "hybrid" rhino embryos can effectively be formed through IVF, after two decades of unsuccessful conventional methods of Assisted Reproduction Techniques.
"ART might offer an option for rescuing genes from the northern white rhino, an essential first step in saving this nearly extinct rhinoceros sub-species," the paper published in June states.
"These methods could play a valuable role in the effort to save rhinoceros populations on the brink of extinction."
Cesare Galli, Thomas Hildebrandt and 11 other colleagues - including University of Melbourne's Marilyn Renfree - who co-authored the report state the next challenge is to transfer the frozen embryos into surrogate southern white rhino mothers to carry them to term.
Dvur Kralove Zoo international projects spokesman Jan Stejskal, who helped write the report, said he'd been part of efforts to save the northern white rhinos for 40 years.
"We now see clearly, as ever more, our obligation to not only to help northern white rhinos but to help them to somehow survive in captivity or in human care but later to even help them get back to their original range and be wild again," he told reporters.
Professor Hildebrandt told reporters he realised in about 2008 there was "no chance to save the sub-species" with techniques available at the time, so they began collecting semen in the hope of rescuing the species.
IVF has previously been used in large mammals including horses, successes the report draws upon.
