Pregnant rhino could help save subspecies

SAN DIEGO — A southern white rhino has become pregnant through artificial insemination at the San Diego Zoo Safari Park — giving hope for efforts to save a subspecies of one of the world’s most-recognizable animals, researchers announced Thursday.

Scientists will be watching closely to see if the rhino named Victoria can carry her calf to term over 16 to 18 months of gestation.

If she does, researchers hope someday she could serve as a surrogate mother and could give birth to the related northern white rhino, whose population is down to two females after decades of decimation by poachers. The mother and daughter northern white rhinos live in a Kenya wildlife preserve but are not capable of bearing calves. Victoria, a southern white rhino, is pregnant at the San Diego Zoo Safari Park in Escondido, Calif. The gestation period for a rhino is 16 to 18 months, and if Victoria can successfully deliver, it is hoped she might someday serve as a surrogate mother for the northern white rhino, which is nearly extinct.

News of Victoria’s pregnancy was confirmed two months after the death of the last northern white male rhino named Sudan, who was also at the Kenya preserve and was euthanized because of ailing health in old age.

Victoria is the first of six female southern white rhinos that the San Diego Zoo Institute for Conservation Research is testing to determine if they are fit to be surrogate mothers. If she and the others are deemed fit, they could carry northern white rhino embryos sometime within the next decade as scientists work to re-create northern white rhino embryos.

There are no northern white rhino eggs, so creating an embryo would require using genetic technology. Scientists plan to use frozen skin cells from dead northern white rhinos to transform them into stem cells and eventually sperm and eggs. Then the scientists would use in vitro fertilization to create embryos that would be put in the six female rhinos.

But more challenges lie ahead, with artificial insemination of rhinos in zoos rare so far and resulting in only a few births.

Victoria is a healthy 747pound rhino estimated to be seven years old.

She and the other five female rhinos were all born in the wild and relocated to San Diego’s Safari Park in 2015. Scientists will soon start developing artificial insemination techniques and embryo transfer techniques for them.

While embryos have been created for southern white rhinos, they haven’t been for northern white rhinos.

The San Diego Zoo Institute for Conservation Research has the cell lines of 12 different northern white rhinos stored in freezing temperatures at its “Frozen Zoo.”