Tag Archives: Fertilization

Northern white rhino eggs fertilized in bid to save the species

In about 10 days’ time, we’ll see if it worked or not.

Researchers in Italy report fertilizing eggs collected from the last two females of the species. There are no living male northern white rhinos currently in the world, so the team used frozen sperm from Sudan, the now-dead last male.

In about 10 days, we’ll know if any have developed into an embryo. The plan is to help the species reproduce via a surrogate mother rhino.

All the eggs in one basket

“We expect some of them will develop into an embryo,” says Cesare Galli, co-founder of the Avantea lab where the work was carried out. Galli is also the corresponding author of the study detailing the process.

The female rhinos currently live at Ol Pejeta, a wildlife conservancy nearly three times the size of San Francisco in the heart of Kenya. Out of the 10 eggs that were recovered in June, only 7 could be used in the process.

The male, a 45-year-year-old named Sudan, became “The Most Eligible Bachelor in the World” on the Tinder dating app in a fundraising effort. He was euthanized after age-related complications last year. Researchers froze his sperm as they prepared for this current procedure. Galli quips that it is better not to “get to the last two individuals before you use this technology.”

The end goal is to raise a herd of at least five individuals and re-introduce them in their natural habitat, which could take decades to accomplish.

In the meantime, there’s the issue of poaching. The northern white rhino was driven extinct by poachers killing the animals for their horns. Advocacy group Save the Rhino says that roughly 2,360 northern white rhinos roamed Chad, the Central African Republic, Sudan, the Democratic Republic of the Congo, and Uganda as recently as 1960. By 1984, it dropped to about 15.

Other rhino species are also prey for poachers, but they’re not in as dire shape as the northern white. Reintroducing five animals into the wild won’t do any good as long as there are still poachers around.

The paper “Embryos and embryonic stem cells from the whiterhinoceros” has been published in the journal Nature.

Researchers are one step closer to saving the northern white rhino from complete extinction

Researchers in Europe have fertilized a rhino egg in vivo and then successfully transferred it back to the female. Their plan is to now perform the same procedure for the northern white rhino, to save the species from extinction.


Rhinos are under extreme pressure from habitat loss and poachers.
Image via Pixabay.

The procedure was performed by an international team of European researchers at the Chorzow zoo in Poland and involved a southern white rhino female. The work came as part of the BioRescue Project, an international team of scientists and conservationists trying to use IVF to save the almost-extinct northern white rhino.

Last of their kind

“This is the first positive proof that the entire procedure we’ve developed in theory can be successful,” said Thomas Hildebrandt (link in German) of the Leibniz Institute for Zoo and Wildlife Research in Berlin, who participated in the project.

There are only two northern white rhinos left in the world — and they’re both females. The last male (whose name was Sudan) died in March 2018 shortly after starting a Tinder account. However, researchers had preserved frozen samples from several males beforehand, as a kind of insurance policy that the species won’t be completely wiped out. Due to a lack of northern white rhinos, they’re testing the IVF transfer on southern white rhinos, a closely related sub-species whose numbers have stabilized in the wild. They now report that the transfer was successful.

As such, the BioRescue team was applied for permission from the Kenyan government to harvest eggs from the last two surviving northern rhino females — a mother and daughter called Najin and Fatu — and are currently awaiting a reply. Kenya’s ambassador in Germany, Joseph Magutt, said his country supports the effort but didn’t say how long it would take for the process to move forward.

The IVF technique is required in this case because the two females are unable to bear offspring themselves; once their embryos are fertilized in the lab, they will be implanted in a southern white rhino surrogate mother.

However, not all is rosy. Hildebrandt says that ultrasound tests show the embryo transferred at Chorzow zoo has grown, but that it’s smaller than expected. As of yet, it’s also unsure whether the embryo will implant in the female’s uterine lining, resulting in a pregnancy. In the meantime, the BioRescue team is working on ways to turn preserved skin cells (from deceased rhinos) into eggs or sperm.

Should it be successful, the technique would offer a safety net for other species on the brink of collapse — and there are many. A recent United Nations report warned that a million species are at risk of extinction in the coming decades, largely because of human activity.