Tigers and rhinos top the Cites (Convention on International Trade and Endangered Species) list of endangered species, followed by deer and bears.

Some plant species are also at risk, with wild plants being taken from their natural environment to be grown on farms.

The World Wildlife Fund says the overseas market for Chinese medicines is likely to rise to $12 billion a year in the next 10 years, from $1 billion in the past decade.

Rhinos and tigers top the list of endangered species

China has to meet strict standards banning the use of endangered species for its traditional medicine exports to Europe and North America. The use of such animals is also illegal inside the country.

However an underground market fed by smuggling continues to flourish, says James Harkness, director of WWF's China programme.

Many people in China still rely on the traditional medicines from complex recipes of plant and animal parts dating back some 3,000 years.

Ferocious as a ... mouse

Practitioners say one major hurdle in persuading people to accept substitutes is the glamorous image of animals used in the medicines.

Tiger bones are used to treat rheumatism and to promote bone healing, while rhino horn has been used for fevers.

There is growing demand for alternative medicines

"Other than it's clinical effect, another reason for using tiger bones is that the animal is often portrayed by the Chinese as ferocious and heroic," says Huang Lixin, president of the American College of Traditional Chinese Medicine.

Although the bones of the sailong mouse are certified in China as a substitute in a famous tonic, it is difficult to get consumers to change long-held beliefs.

The power and grandeur of tigers is a common theme in Chinese language, literature and opera "so people have the idea that Tiger Bone Wine makes a person strong as a tiger", she says.

Traditional Chinese medicine specialists have proved some substitutes effective in tests. Dog bones and herbs such as ginger have shown promise as an alternative to tiger bones.