Northern white rhinos could be SAVED from extinction after vets harvest eggs from the last two surviving members of the species
- Females Najin, 30, and Fatu, 19, cannot carry calf and live under guard in Kenya
- Scientists have harvested five oocytes from each of the northern white rhinos
- The eggs cannot be frozen and were flown to a laboratory in Italy to be fertilised
- Resulting embryos will be frozen until placed in southern white rhino surrogate
Northern white rhinos could be saved from extinction after eggs were successfully harvested from the final two remaining females yesterday.
Science is the only hope for the species after the death in March 2018 of the last male, named Sudan, at the Ol Pejeta Conservancy in Kenya.
Females Najin, 30, and daughter Fatu, 19, live under 24-hour armed guard at Ol Pejeta however neither is able to carry a calf.
On Thursday an international consortium of scientists managed to harvest 10 oocytes from the two females and send the eggs to Italy to be fertilised.
Scientists have successfully harvested eggs from the last remaining northern white rhinos Najin, left, and Fatu, right, in an attempt to save their species (file picture)
Neither Najin or Fatu, pictured after receiving medication in her enclosure at Ol Pejeta Conservancy on Wednesday, can carry their own calves
Professor Thomas Hildebrandt from the Leibniz Institute for Zoo & Wildlife Research in Germany carried out the procedure this week.
He said: ‘We were able to harvest a total of 10 oocytes – five from Najin and five from Fatu – showing that both females can still provide eggs and thus help to save these magnificent creatures.
‘Both the technique and the equipment had to be developed entirely from scratch.’
The eggs – which cannot be frozen – were immediately flown to a laboratory in Italy to be fertilised with cryogenically frozen sperm, of which there are samples from four deceased males.
The resulting embryos will then be frozen until they can be transferred into a surrogate mother from the southern white rhino subspecies. The first such rhino embryos using in-vitro techniques were created last year.
The team working on the project also includes Italian biotech laboratory Avantea, Czech zoo Dvur Kralove and the Kenya Wildlife Service (KWS).
The last male of the species Sudan, pictured with head caretaker Mohammed Doyo, died last year aged 45 in Kenya after suffering from a degenerative muscle and bone condition
After harvesting the eggs from the two female rhinos, pictured in their enclosure, scientists sent them immediately to a laboratory in Italy
Eggs can only be collected three times a year, and a lack of genetic diversity could hamper the survival of the species. Both Najin, 30, and Fatu, 19, pictured together, are related to Sudan
John Waweru, KWS director general, said: ‘We are delighted that this partnership gets us one step closer to prevent extinction of the northern white rhinos.
‘This is particularly touching given the heartbreaking death of Sudan, the last male, who died of old age last year in Kenya.’
Sudan gained worldwide fame in 2017 after he was featured on the popular dating app Tinder in an effort to raise money for the IVF procedure.
If the IVF is successful, scientists say there may be several births of northern white rhino calves, but the approach has its limits.
Eggs can only be collected from the females three times a year, and a lack of genetic diversity could hamper the survival of the species.
Rhino Fatu has degenerative lesions in her uterus and Najin has weak hind legs which could cause complications if she fell pregnant, meaning they can’t carry their own calves.
The technique and the equipment to extract the females’ eggs had to be developed entirely from scratch. Pictured is British actress Liz Hurley and Russian entrepreneur Evgeny Lebedev with Sudan in 2016, two years before he died
However the consortium of scientists known as BioRescue is also trying to create artificial sex cells known as gametes via stem cell transformation from the frozen tissue of other, unrelated northern white rhinos, to diversify the gene pool.
According to the team working on the project, the aim is to reintroduce the rhino into secure habitats within the areas they used to roam. This could take up to 70 years.
There are five rhino species remaining on earth of which black and white rhinos are found in Africa. The northern white rhino is generally considered a subspecies of white rhino although some scientists believe it to be a sixth species.
Rhinos have few predators in the wild due to their size.
However, demand for rhino horn in traditional Chinese medicine and dagger handles in Yemen fuelled a poaching crisis in the 1970s and 1980s that largely wiped out the northern white rhino population in Uganda, the Central African Republic, Sudan and Chad.
By 2008 the northern white rhino was considered extinct in the wild.
Modern rhinos have plodded the earth for 26 million years. As recently as the mid-19th century there were more than one million in Africa. The western black rhino was declared extinct in 2011.
HOW DO SCIENTISTS HOPE TO SAVE THE NORTHERN WHITE RHINO USING IVF?
While the death of Sudan marked a symbolic turning point in the fight to save the northern white rhino, in fact the survival of the species has been entirely reliant on untested IVF techniques for years.
It was hoped that Sudan, his daughter Najin and granddaughter Fatu might be able to produce offspring when they were moved to Kenya in 2009, but their close genetic relationship rendered them infertile.
Since at least 2015 scientists have been working with IVF and stem cell techniques in the hopes of being able to create a viable northern white rhino embryo, according to a GoFundMe page for the project.
Researchers in Berlin and San Diego are using DNA samples collected from a dozen northern whites, including Sudan, and trying to apply techniques developed for humans to the animal.
Kenya Wildlife Service vet Dr Dominic Mijele, left, and Ol Pejeta’s vet Dr. Stephen Ngulu, right, disconnect an intravenous line from Najin this week
If a viable embryo can be created, it would then have to be implanted into the womb of a southern white rhino.
While the southern white rhino would be responsible for giving birth to the baby, because the infant’s genetic material came solely from northern whites, it would be a member of that species.
However, as Save The Rhino points out, the process is fraught with difficulty and has a low chance of success.
Female northern white rhino Najin is pictured recovering in her enclosure after having eggs removed at Ol Pejeta Conservancy, Kenya
In the last 15 years just 10 rhino births have resulted from artificial insemination and only two embryos have ever been created – one of which divided into two cells before perishing, and the other one into three.
For the northern white rhino to be genetically viable a minimum of 20 healthy individuals must be born – meaning the whole process must be successfully completed 20 times – to avoid inbreeding.
Then, it would be necessary to find a suitable habitat for them, since their old habitat has largely been destroyed and led the species to the brink of extinction in the first place.
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