Vivian, a nubile giraffe in the Peoria Zoo in Illinois, is back on the pill after shunning the contraceptive-laced food that she was served for about a month.
While zookeepers scrambled for a solution to the long-necked, 18-month-old spotted vixen's finicky eating habits, they separated her from Taji, the menagerie's sexed-up male giraffe that had eyes for the spotted specimen since she arrived in November.
Zoo officials put Vivian on birth control to prevent her from mating with Taji, because the pair aren't considered a good genetic match.
"We look at the whole population [of giraffes] in North America," said Peoria Zoo Director Yvonne Strode, "and the ones that don't have a lot of brothers and sisters and cousins are the valuable ones. We want to capture their genes."
"Taji is mid-range, he's fairly valuable," Strode told AOL Weird News, "but Vivian's at the bottom."
All zoos in North America coordinate to maintain genetic diversity between animals, TV-station WMBD reported.
To avoid unwanted pregnancies, the zookeepers initially added an eight-pound serving of grain mixed with contraceptives to Vivian's diet after she hit puberty. She cooperated by eating the full dosage for a while. But then she stopped eating the full helping, which renders the birth control ineffective.
The solution was to switch the hoofed creature to a liquid birth control that's mixed with grain and wrapped in a lettuce leaf and fed to her in a smaller portion than the previous contraceptive.
Though the notion of animal birth control is surprising to many people in the general public, it's a routine measure for zoos to keep their populations in check.
People for the Ethical Treatment of Animals, a group that advocates against zoos, supports the policy of controlling the populations of animals born into captivity.
"I'd rather zoos weren't there at all, and that all the animals had freedom of life," said PETA President Ingrid Newkirk, "We're fine with [putting animals on birth control], because we wish animals were in their natural habitat rather than displayed like wind-up toys."
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