March 2, 1996
Web posted at: 6:50 a.m. EST
From Correspondent Ann Kellan
SAN DIEGO, California (CNN) -- Meet Nola and Nadi, two huge northern white rhinoceri that San Diego scientists hope to breed with male white rhinos.
The only problem: Nola and Nadi are girlfriends.
"It's the bottom of the ninth inning, and we have two outs and two strikes," says Oliver Ryder, a geneticist.
And scientists are looking for a home run as they try to save the northern white rhinos from extinction. About 40 remain in the world.
So what happens when scientists try to breed Nola and Nadi?
Well, researchers hoped the females would swoon over Angi, a mammoth male northern white rhino. But unfortunately, after Angi tried interacting with the two, the females wanted nothing to do with him. (471K QuickTime movie)
After that plan failed, zookeepers and researchers separated the two females temporarily and put aphrodisiac-type hormones in their food to make them more receptive to males and mating. Nola and Nadi were first given a hormone called prostaglandin, followed by a more extensive, two-week daily dose of oral progesterone.
In Nola's case, the treatment worked. She mated with Saut, another male white rhino, for 20 to 30 minutes.
"It's amazing to me how the female can withstand the weight of the male for a very prolonged breeding," said Barbara Durant of the San Diego Zoo.
Yet Nadi is a different story. She's 26 years old, her biological clock is ticking and she initially showed no interest in male counterparts.
Researchers are now trying to pair her with Saut in hopes Nadi will follow Nola's lead.
But before researchers let Saut and Nadi roam together, an ultrasound was needed to make sure Nadi is able to reproduce.
The scientists and zoologists corralled Nadi and zonked her with a tranquilizer as they prepared for the ultrasound. When she flopped over, Nadi landed unhurt against a wall, but in a position where researchers could not easily perform the task. A bulldozer was then used to move Nadi's three-ton body, and researchers successfully performed the procedure. (333K QuickTime movie)
Since the ultrasound, Nadi has paid some attention to Saut. Meanwhile, Saut and Nola continue to mate, meaning Nola is most likely not pregnant yet. If things continue, Nola and Nadi might be more than good friends -- they'll be mothers.
If so, it would be the first northern white rhino born in North America.
Copyright © 1996 Cable News Network, Inc.
ALL RIGHTS RESERVED.
External sites are not endorsed by CNN Interactive.