Chinese animal keepers have called on the services of Viagra

This is an old story dating back to late 2001. BEIJING, China (CNN) -- In a desperate bid to get numbers of an endangered species of tiger up, Chinese animal keepers have called on the services of Viagra.

The anti-impotency drug is being used to try and encourage a pair of rare South China tigers in a Beijing zoo to mate, the Beijing Morning Post reported Wednesday.

Chinese animal breeding specialists have in the past tried a number of alternative methods to try and boost numbers of animals close to extinction. For instance, they showed pandas 'pornographic' films of other pandas having sex to try and provoke some animal instincts amongst the endangered sex-shy mammals. Now, Viagra is being used in combination with other drugs to try and increase the sexual appetite of the tigers.

There are only 49 South China tigers in captivity in 10 Chinese zoos, the South China Tiger Conservation Coordination told the Beijing Morning Post, and the species is on the brink of extinction. Fewer than 20 are believed to exist in the wild but the problem is compounded because the tiger loses its sexual drive when in captivity.

Only one South China tiger was born in the last year despite a six-year breeding program by the Conservation Coordination. Whether the introduction of Viagra is a success or not will be determined if the two tigers can produce offspring by next year. The South China tiger is one of the smallest tiger subspecies with a male growing to around 2.5 meters (8 feet) head to tail and weighing about 150 kilograms (330 pounds).

But extinction fears are not confined to the South China tiger. There are an estimated 5,000 tigers left in the world, down from around 100,000 at the start of the 20th century. Habitat loss and poaching continues to threaten the tiger's existence. Although banned in many countries, the tiger is still hunted with the belief that its skin, claws and penis have great medicinal value. In particular, tiger penis, under traditional Chinese medicine, is said to increase sexual drive and potency.