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The international BioRescue consortium has entered new grounds in its mission to save the northern white rhinoceros (NWR, Ceratotherium simum cottoni) from extinction. Since the beginning of the year, it has produced three additional northern white rhino embryos.

Also, it initiated embryo transfers during which pure NWR embryos are transferred to surrogate southern white rhino mothers. With only two surviving NWR females—Najin and her daughter Fatu—both unable to carry a pregnancy naturally, BioRescue is using cutting-edge assisted reproduction and stem cell technologies to restore the species.

On August 22, it was six years since the first collection of oocytes in Fatu and Najin at Ol Pejeta Conservancy, Kenya. Since then, the BioRescue consortium led by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), Germany, and coordinated by Safari Park Dvůr Králové, Czechia, has conducted 21 oocyte collections from the northern white rhino female Fatu. Three of the collections were performed this year and yielded three new northern white rhino embryos that were produced in the Avantea laboratory in Italy. In total, the team has now produced 38 pure northern white rhino embryos.

In close cooperation with the Kenya Wildlife Service and Wildlife Research and Training Institute, the team also recently started with embryo transfers using a pure northern white rhino embryo. Proof of concept was delivered at the end of the year 2023 when the BioRescue team achieved the first ever pregnancy in a rhinoceros after IVF with a southern white rhino embryo.

Following the establishment of a new surrogate group of rhinos, BioRescue conducted embryo transfer with a NWR embryo in July 2024, December 2024, and May 2025. Unfortunately, none of these attempts has led to a lasting pregnancy, although mucus development in the recipient uterus was observed after the December 2024 transfer. However, subsequent analysis was inconclusive and did not confirm NWR DNA.

As with all procedures performed by the BioRescue team, the first embryo transfers with a pure NWR embryo underwent a detailed ethical evaluation by experts from the University of Padua, Italy, and had no negative health effects on the surrogate southern white mothers. The same applies to the northern white rhino female Fatu, whose ovarian health actually appears to have benefited from repeated procedures—a phenomenon referred to as Ovarian Cleansing Therapy.

The sixth anniversary of the first oocyte collection in Najin and Fatu also coincides with wider recognition of the BioRescue team's efforts. On August 24, 2025, National Geographic premiered the documentary The Last Rhinos: A New Hope, streaming now on Disney+ and Hulu. Award-winning National Geographic photographer Ami Vitale follows the team's extraordinary journey at Ol Pejeta Conservancy and beyond, documenting the urgency, setbacks, and triumphs of producing the world's first surrogate rhino pregnancy, while highlighting the deep bond between the rhinos and their caretakers.

The film underscores that science is rarely linear—every egg retrieved, embryo produced, and attempt made is a vital step forward. Viewers will see how BioRescue's blend of cutting-edge science, international collaboration, and profound dedication offers not only hope for the NWR but a blueprint for saving other species on the brink.

After the BioRescue team received a prize for the best research published in the journal Reproduction in the beginning of the year 2025 (please, see more ), the National Geographic documentary is another confirmation of truly global importance of the BioRescue efforts.

Alongside its work at Ol Pejeta and embryo production in Avantea, the BioRescue consortium is also advancing stem cell and ancient DNA technologies to increase the genetic diversity of the future founding population of the northern white rhino. Researchers at the University of Osaka and the Max Delbrück Center, Berlin, are focusing on the generation of functional oocytes derived from pluripotent stem cells. The ultimate goal of these efforts is the reintroduction of the northern white rhino to its original range.