ESCONDIDO — A southern white rhinoceros at the San Diego Zoo Safari Park in Escondido has been successfully impregnated through artificial insemination for the first time in the zoo’s history, which, for the northern white rhino, could help pave the way back from the brink of extinction, zoo officials said.
Victoria, one of six female southern white rhinos at the Safari Park, is only seven weeks into her pregnancy, which if successful will last 16 to 18 months.
“Victoria is part of our one-of-a-kind rescue program to save her cousins, the northern white rhino,” said the San Diego Zoo Global Wildlife Conservancy.
“With only two left on Earth, and both of them female, the northern white rhino has been poached to the brink of extinction.”
But conservation experts at the zoo and elsewhere have a plan to bring back northern white rhinos “using cutting-edge science and decades of animal care expertise,” zoo officials said. “Though Victoria and her embryo are southern white rhinos, this is an
important first step, proving the science is working.”
Nola, then one of four remaining northern white rhinos, died at the Safari Park on Nov. 22, 2015. Then on March 19 of this year, Sudan, the last male northern white rhino, died in a preserve in Kenya.
But just three days later, on March 22, animal experts at the Safari Park were able to artificially inseminate Victoria. Should her developing baby survive until birth, it would give scientists hope of repeating the feat of artificial insemination using genetic material from northern white rhinos.
Victoria is one of six female southern white rhinos brought to the Safari Park from a preserve in South Africa in 2015 with the specific hope they could breed northern white rhinos. Scientists at the Safari Park’s Nikita Khan Rhino Rescue Center have spent years training and conditioning Victoria and the other five females to receive needed medical procedures.
Last July, zoo officials announced they had made their first attempt to artificially inseminate a southern white rhino when they tried with 9-year- old Amani. That impregnation attempt apparently failed.
The project to save northern white rhinos and other endangered species goes back decades to when Oliver Ryder, a geneticist at San Diego Zoo Global, suggested deep-freezing tissue from the endangered animals in the hope that future technology could use the genetic material to reproduce the animals, the San Diego Union-Tribune reported. That technology finally arrived in 2007
thanks to the work of Japanese scientist Shinya Yamanaka, who demonstrated that adult mammalian cells can be turned into artificial embryonic stem cells.
Jeanne Loring, a stem cell scientist at The Scripps Research Institute, told the Union-Tribune that Victoria’s pregnancy is “an amazing feat” and “a milestone.” She also said that the zoo and researchers like her have had to invent technology as they’ve gone along because much of the rhino reproductive system hasn’t been studied before.
Loring told the Union-Tribune the process of artificially inseminating a southern white rhino to carry a northern white rhino would be much more complicated than it sounds: thawed cryopreserved tissue from a northern white rhino must be converted into artificial embryonic stem cells, then matured into egg and sperm cells. These would then be united by in vitro fertilization to create an embryo, which would finally be implanted into the southern white rhino surrogate mothers.
Safari Park officials say the work may be applicable for other rhino species, including the critically endangered Sumatran and Javan rhinos.
The zoo’s conservation program relies on donors and last year received a pledge of a matching gift of up to $1 million from Oracle Corp. founder Larry Ellison and his girlfriend, Nikita Kahn, who previously gave the zoo over $1 million to fund the 3.5-acre rhino rescue center that now bears her name.