The world's first successful embryo transfer in rhinos, thanks to research carried out by a Cremona-based company, paves the way for saving northern white rhinoceros specimens from extinction.

The international team of scientists and conservationists behind the BioRescue project, led by the Italian company Avantea, to save the northern white rhino has succeeded in achieving the world's first pregnancy in a rhino after an embryo transfer.
As communicated on its social channels by the Ol Pejeta reserve in northern Kenya, the southern white rhino embryo was produced in vitro from harvested oocytes and sperm and was transferred into a surrogate southern white rhino mother in Ol Pejeta in September 2023.
Only 70 days later, the team confirmed a pregnancy.

"This extraordinary achievement is a milestone in the mission to save the northern white rhino, as it proves that the process works and it will now be possible to take this crucial step, embryo transfer with a northern white rhino embryo, for the first time," they comment from the Ol Pejeta Conservancy. "The health and well-being of the southern white rhino surrogate mother Curra and the southern white rhino male Ouwan were closely monitored throughout the process. Both healthy rhinos showed no complications or adverse effects from the procedure, but in late November came the devastating news that both Curra and Ouwan were found dead.

It was discovered that extremely heavy rainfall, linked to climate change, had caused the surrogate enclosure to flood and released spores of dormant Clostridia bacteria that had infected and killed both rhinos. A crisis team was set up that established rapid and effective measures to protect all semi-captive rhinos, including the last two northern white rhinos Najin and Fatu. The measures included a vaccination programme and quarantine of the affected areas.

Quick action prevented further rhino deaths and two months later, the BioRescue project started to identify the next surrogate mothers and the booster bull.
After the above steps, which are likely to take several months, an embryo transfer with a northern white rhino embryo will follow.