They create hybrid embryos of white rhinos in danger of extinction
Synthetic embryos could be implanted in females of this animal and avoid its disappearance.
This is the first time hybrid embryos of this species have been created and this finding offers a small glimmer of hope to save the northern white rhinoceros (Ceratotherium simum). It's the last hope.
Rhinoceros embryos manufactured in the laboratory
A team of Italian and German scientists has achieved hybrid embryos of northern white rhinoceros (Ceratotherium simum cottoni) and southern white rhinoceros (Ceratotherium simum simum) prepared to be implanted in the uterus of a female of this animal. It is the first attempt at artificial insemination in rhinoceroses
The scientists injected preserved sperm from a male northern white rhinoceros in female southern white rhinoceros eggs, a closely related subspecies. They did it through an "intracytoplasmic injection", a technique that consists in introducing the sperm inside the ovule. The embryos were incubated until the cells began to differentiate, a stage in which they can be implanted in a surrogate mother, according to researchers report in the journal Nature Communications.
This achievement represents "one of the really crucial steps" to get new rhinoceroses born, says Jan Stejskal, coordinator of conservation efforts for the northern white rhinoceros in Safari Park Dvůr Králové in the Czech Republic and co-author of the study.
Experts hope to implant similar embryos in female southern white rhinos or hybrid white rhinos from north to south.
If it works, it could offer the hope of bringing a species back to the verge of extinction. Sudan, the last white male of the white rhino, died this March. Only two females survive in Kenya (Najin and Fatu) and both are infertile. In comparison, there are more than 20,000 white rhinos in the south.
The hybrid rhinos, if they manage to be born, could serve two purposes. They could be more compatible surrogate mothers for a possible embryo of northern white rhino since they will share more DNA with the babies. And theoretically, the hybrids could be bred selectively with the genes of the northern rhinoceros, creating a pure northern white rhinoceros, a process that would take many generations and span several decades, but which seems plausible.
In a potentially faster way to give birth to a pure white rhinoceros from the north, researchers plan to harvest eggs from the remaining two females and combine them with preserved northern rhinoceros sperm. If it succeeds, within the next three years, we could witness the birth of a small white rhinoceros from the north.
Stem cell technology has also played an important role, since the team was able to derive pluripotent stem cells, which can be converted into any cell in the body, including ovules and sperm, from two southern white embryos pure Scientists claim that there are 12 frozen cell lines of northern white rhinos, six of which are genetically distinct, which is important to avoid inbreeding. If researchers can convert these skin cells first into pluripotent stem cells and then into eggs and sperm, it would be another way to create a pure white rhinoceros embryo from the north.
For now, other scientists warn against over-optimism. "Saving a species or a subspecies requires much more than science," says Terri Roth, an animal reproduction physiologist at the Cincinnati Zoo and Botanical Garden.
Africa is in the midst of an epidemic of rhino poaching. Thomas Hildebrandt, leader of the work, agrees. "The white rhinoceros of the north did not become extinct because it failed in the evolution, it failed because "it is not bulletproof ", sentence.