• Females Najin and Fatu at Ol Pejeta Conservancy, Kenya, are the only remaining northern white rhinos in the world.
• They were cryopreserved on Christmas eve when they reached the blastocyst stage suitable for freezing and increase the total number of viable embryos produced.
The efforts to prevent the extinction of the Northern White Rhino through advanced assisted reproduction technologies is still bearing fruits.
The international consortium of scientists and conservationists that is working towards preventing it announced that two new embryos were produced last month.
On December 13 last year, the team of Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), Safari Park Dvůr Králové, Kenya Wildlife Service and Ol Pejeta Conservancy successfully performed an oocyte collection in Kenya.
After immediate transportation of the recovered oocytes across continents, the embryos were created at Avantea laboratory in Cremona (Italy) following maturation and fertilisation of the oocytes with the semen of Suni.
They were cryopreserved on Christmas eve when they reached the blastocyst stage suitable for freezing and increase the total number of viable embryos produced so far to five.
This nourishes the hope that despite challenges and delays caused by Covid-19 the northern white rhino can still be saved.
Females Najin and Fatu at Ol Pejeta Conservancy, Kenya, are the only remaining northern white rhinos in the world.
To prevent the extinction of the northern white rhino, an international consortium of scientists and conservationists harvest immature egg cells (oocytes) from the two females.
They artificially inseminate these using frozen sperm from deceased males in order to create viable northern white rhino embryos.
In the near future, the embryos will be transferred into southern white rhino surrogate mothers to create northern white rhino offspring.
The embryos are now stored in liquid nitrogen along with the three embryos from previous procedures.
Unfortunately, no oocytes were retrieved from Najin, who is Fatu’s mother. Previously, collecting oocytes from Najin was successful, but no embryos were created from her egg cells.