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Cairo zoo puts lions on human birth control pill

Vets at Cairo's Giza Zoo are experimenting with birth control on their rapidly expanding population of lions.

They are taking the unusual step of giving the big cats human birth control pills after a population explosion that means there are now 53 lions at the zoo.

It is a controversial move in a zoo which has already been criticised by animal rights activists.

Jon Leyne reports from Cairo.

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