Taiwan has been experimenting with a simple solution to the perennial problems of pollution, smell and excessive water use on pig farms: train the pigs to use a toilet.

After some encouraging results the government now wants all the island's pig farms to adopt the practice as it looks to burnish its green credentials, offering cash to farmers and pushing the benefits such as less watery manure that can be sold at higher prices.

"To use the pig waste as manure is a very good approach within the spirit of green energy, much better than just letting it go to waste and pollute river water," said Stephen Shen, head of Taiwan's environment department. "And I think that can help us a lot in decreasing CO2 emissions and fighting global warming."

The "toilet" consists of a series of iron bars installed about 20 centimeters above the floor in the corner of a pen. Pigs step between the bars to go about their business, with the waste collected in a single, easy-to-clean spot.

If all the around 6 million pigs in Taiwan used such toilets, the government estimates the around 180 million liters of water used per day in cleaning would halve.

Chang Chung-Tou, general manager of Long Kow Foods Enterprise, a pig farm with toilets in the western -Taiwan county of Yunlin, says his potty-trained porkers live longer.

"Because we don't need to flush the whole cage with water, the pigs are also less likely to catch colds. That helped us to raise the survival rate of our pigs from 70 to 90 percent," Chang said.