New embryos developed to save rhinos from extinction
Hopes of reversing the imminent extinction of the northern white rhinos have been revived after an international consortium of scientists and conservationists successfully created two embryos of the species in an Italian laboratory, with Kenya playing a key role.
The embryos, stored in liquid nitrogen pending transfer into a surrogate mother “in the near future”, were created using immature eggs from the two remaining Kenya-based females and frozen sperm from deceased males.
Ten eggs were harvested from two rhinos Najin and Fatu— a mother and a daughter living at Ol Pejeta Conservancy in Laikipia where they were brought from Dvur Kralove Zoo in the Czech Republic in 2009 to facilitate breeding.
Prof Cesare Galli, who leads the team, said the eggs from the two only surviving northern white rhinos were fertilised with frozen sperm harvested from 34-year-old Suni, who died on October 17, 2014 of natural causes in his enclosure in Ol Pejeta, and Saut.
“We brought 10 oocytes (immature eggs) from Kenya, five from each female. After incubation, seven matured and were suitable for fertilisation (four from Fatu and three from Najin),” Galli said yesterday.
The successful egg collection was a joint effort by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), Avantea, Dvur Králové Zoo, Ol Pejeta Conservancy and the Kenya Wildlife Service (KWS). Immediately after the collection, the eggs were airlifted to the Avantea Lab in Cremona.
Fatu’s eggs, Galli said, were injected with Suni’s sperm while Najin’s eggs were injected with Saut’s sperm using the unprecedented and costly procedure called Intra Cytoplasm Sperm Injection (ICSI).
Saut’s semen was, however, of poor quality and the team had to thaw additional samples to find viable sperms.
“After 10 days of incubation, two of Fatu’s eggs developed into viable embryos that were preserved for future transfer.
Najin’s eggs did not make it to a viable embryo despite the fact that one egg initiated segmentation,” the professor said of the first time-ever procedure.
Tourism Cabinet Secretary Najib Balala and KWS Director General Brig (rtd) John Waweru celebrated the milestone, described variously as an “assisted reproduction that may be a pivotal turning point in the fate of these magnificent animals”.
“The Kenyan government is greatly encouraged by breaking of new ground in the assisted reproduction technique and remains committed to facilitating the pioneering process all the way.
It has been a decade of race against time and we are excited at the progress in reversing the hitherto bleak outlook for the northern white rhino,” said Balala.
Waweru added: “The pioneering in vitro embryos of the northern white rhino is a strong testament to what committed partnership can achieve in pushing the frontiers of science to save a creature from extinction.”
Prof Thomas Hildebrandt from Leibniz-IZW said: “Today, we achieved an important milestone, which allows us to plan the future steps in the rescue programme of the northern white rhino.”
