Kenya Is Saving The Northern White Rhino Through Laboratory Technologies
For decades the story of the northern white rhinoceros has been a tale of decline. The number of individuals shrank down to only two in 2018, rendering complete extinction as only a matter of time. An international consortium of scientists and conservationists are now working towards reviving the species through ‘assisted reproduction’ .Using eggs collected from the two remaining females and frozen sperm from deceased males, they successfully created two northern white rhino embryos. The embryos are now stored in liquid nitrogen to be transferred into a surrogate mother in the near future.
The in-vitro creation of northern white rhino embryos was achieved at Avantea Laboratories in Cremona, Italy. Prof. Cesare Galli and his team matured and fertilized eggs collected on August 22nd from Najin and Fatu, the two females living at Ol Pejeta Conservancy in Kenya, with sperm from males Suni and Saut.
“We brought ten oocytes back from Kenya, five from each female. After incubation seven matured and were suitable for fertilisation (four from Fatu and three from Najin)”, says Galli. “Fatu’s eggs were injected with Suni’s sperm while Najin’s eggs were injected with Saut’s sperm using a procedure called ICSI (Intra Cytoplasm Sperm Injection). Saut’s semen was of really poor quality and we had to thaw additional samples to find viable sperms for ICSI. After ten days of incubation, two of Fatu’s eggs developed into viable embryos that were cryopreserved for future transfer. Najin’s eggs did not make it to a viable embryo despite the fact that one egg initiated segmentation.”
In a different milestone three weeks ago, scientists were able to collect oocytes (immature eggs) from both Najin and Fatu for the first time ever. The successful egg collection was a joint effort by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), Avantea, Dvůr Králové Zoo, Ol Pejeta Conservancy and the Kenya Wildlife Service (KWS).
Immediately after the collection, the eggs were air-lifted to the Avantea Lab in Cremona. “The entire team has been developing and planning these procedures for years”, says Prof. Thomas Hildebrandt from Leibniz-IZW. “Today we achieved an important milestone on a rocky road which allows us to plan the future steps in the rescue program of the northern white rhino”.
The entire process is part of the “BioRescue” research project. Its goal is to significantly advance assisted reproduction techniques (ART) and stem cell-associated techniques (SCAT) complemented with a comprehensive ethical assessment for the benefit of the northern white rhinoceros. The consortium is partially funded by the German Federal Ministry of Education and Research (BMBF) and comprises internationally renowned institutions from Germany, Italy, Czech Republic, Kenya, Japan and USA. BioRescue aims to prevent the extinction of the northern white rhino.
“In coming months we need to optimize the process of transfer and following development of an embryo in the body of a surrogate mother. The technique for collection of eggs was developed in cooperation with many European zoos and we are happy that this unique cooperation can continue even with attempts at successful embryo transfer”, says Jan Stejskal, Director of Communication and International Projects from Dvůr Králové Zoo, where Najin and Fatu were born.
