Northern White Rhinos (NWR) are functionally extinct, as only two females of this species are left on the planet. An international team of scientists has now successfully created hybrid embryos from Southern White Rhino (SWR) eggs and NWR sperm using assisted reproduction techniques (ART). This is the first, ever reported, generation of blastocysts (a pre-implantation embryo) of rhinos in a test tube. Additionally, the international team established stem cell lines from blastocysts of the SWR with typical features of embryonic stem cells. This breakthrough is published in Nature Communications today.
Oocytes were collected from SWR females in European zoos by IZW and then shipped to AVANTEA, a world leader in assisted reproduction technologies (ART) for large animals in Italy. “In our lab we were able to develop procedures to mature the oocytes, fertilise them by intracytoplasmic sperm injection (ICSI) and culture them,. For the first time we had rhino blastocysts – an early stage of an embryo – developed in vitro, similarly to what we do routinely for cattle and horses,“ reports Prof Cesare Galli, from AVANTEA in Cremona, Italy.
Since then Avantea has generated several embryos from oocytes that were shipped to Cremona by IZW that are now cryopreserved for future transfer into surrogate mothers to carry a pregnancy to term.
At Avantea Dr. Giovanna Lazzari also derived embryonic stem cell lines from two SWR blastocysts.
Combining stem cell research with the now developed ART will provide a blueprint on how to save highly endangered species that have already dwindled to numbers that make conventional conservation efforts impossible.
The future plans are to generate eggs and sperm from embryonic stem cells and iPS cells to widen the genetic base of the future NWR population and to implant the embryos that were cryopreserved into surrogate SWR female to carry a pregnancy to term.
See the accompanying press release and the invitation to the press conference that will take place in Berlin on July 5th.