Embryos contain white rhino DNA

7 pct of Australia reptiles risk extinction

PARIS, July 5, (AFP): Months after the death of Sudan, the world’s last male northern white rhino, scientists said Wednesday they have grown embryos containing DNA of his kind, hoping to save the subspecies from extinction.

With only two northern white rhino (NWR) known to be alive today — both infertile females — the team hopes their breakthrough technique will lead to the re-establishment of a viable NWR breeding population.

“Our goal is to have in three years the first NWR calf born,” Thomas Hildebrandt, head of reproduction management at the Leibniz Institute for Zoo and Wildlife Research in Berlin, told journalists of the work.

“Taking into account 16 months (of) pregnancy, we have a little more than a year to have a successful implantation.”

The team’s work, using a recently patented, two-metre (6.6-foot) egg extraction device, resulted in the first-ever test tube-produced rhino embryos.

Now frozen, these “have a very high chance to establish a pregnancy once implanted into a surrogate mother,” said Hildebrandt.

The hybrid embryos were created with frozen sperm from dead NWR males and the eggs of southern white rhino (SWR) females, of which there are thousands left on Earth.

The eggs were harvested from rhinos in European zoos.

The team now hopes to use the technique to collect eggs from the last two northern white rhinos — Najin and Fatu, the daughter and granddaughter of Sudan. They live in a Kenyan national park.

By fertilising these with northern white rhino sperm and implanting the resulting embryos in surrogate southern white rhino females, the team intends to create a new, fledgling NWR population.

“Our results indicate that ART (assisted reproduction techniques) could be a viable strategy to rescue genes from the iconic, almost extinct, northern white rhinoceros,” the team wrote in the journal Nature Communications.

The researchers have sought permission to harvest eggs from Najin and Fatu in Kenya, hopefully before the end of the year.

But the procedure is not without risk: “we have to do a full anaesthesia, the animal is down for two hours, and it is quite a risky situation” for the last two of their kind, conceded Hildebrandt.

Any hybrids born as a result may play a crucial future role as surrogates, sharing more genes with northern rhinos than purely southern surrogates.

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GENEVA: Australia’s reptiles, including lizards and snakes, are facing growing threats from invasive species and climate change, with seven percent on the verge of extinction, conservationists said Thursday.

In an update to its “Red List” of threatened species, the International Union for Conservation of Nature (IUCN) said virtually all of Australia’s unique reptile species were now considered threatened and that one in 14 risked extinction.

“This Red List update highlights the vulnerability of Australia’s lizards and snakes to invasive alien species,” Philip Bowles, who coordinates IUCN’s work on snakes and lizards, said in a statement.

A full 975 Australian reptile species are currently on the Red List, IUCN said, adding that the vast majority of the threatened species were endemic to Australia.

The island continent is home to an unusually diverse reptile population, which evolved in isolation and represents almost 10 percent of the global reptile fauna.

Invasive species are the main threat to most of the threatened reptiles in Australia, IUCN said, pointing to a recent study showing that invasive feral cats alone kill about 600 million reptiles each year in the country.