This farm in southwestern China breeds billions and billions of cockroaches.

The company - called Gooddoctor - claims to have the biggest farm of its kind.

Inside it's dark, warm and humid, just how the roaches like it.

You might be asking why the world needs more of these pests.

Well, in China, these versatile little bugs mean business.

They're being used for everything from medicine, to food, and even waste disposal.

This factory specializes in breeding roaches for their supposed health benefits.

It's claimed that some parts of the bugs can be extracted and crunched into medicine, curing ailments from stomach illnesses to the common cold.

Researchers are even interested in using them in diet pills and hair loss remedies.

Reuters' Thomas Suen was brave enough to tour the facility: (SOUNDBITE) (ENGLISH) REUTERS VIDEO JOURNALIST, THOMAS SUEN, SAYING: "Now the giant tanks behind me they've been using for producing Chinese traditional medicine from the cockroaches, the company first fries the cockroaches and puts them into the tank and then they extract the valued parts from the cockroaches for the traditional Chinese medicine." Farms like these are popping up across China, this company in the eastern Shandong province uses them as a novel form of waste disposal.

China is facing something of a garbage crisis.

Expanding cities are generating more food waste than they can handle.

Enter the roach.

These little pests can munch their way through mountains of food scraps.

Fifty tonnes a day to be exact.

And without getting too graphic - the waste the roaches create, can then be recycled into fertilizer.

The company already has plans to set up three more plants in the new year.

And it's not just big companies interested in the little bugs.

Li Bingcai is the proud owner of three million roaches.

His remote village already has two farms. His goal is to create 20.

He's made a business out of selling them as livestock feed.

Sometimes, they also provide a tasty treat for his family.