Scientists in the US have developed technology that can turn cow manure into drinkable water.

The machine takes the manure and passes out water which is clean enough for livestock to drink - by removing compounds like ammonia.

Nutrients are also pulled from the waste, which can be turned into fertiliser.

Professor Steve Safferman, from the Michigan State University team, said: "If you have 1,000 cows on your operation, they produce about 10 million gallons of manure a year.

The system produces 227 litres of water for every 455 litres of manure digested.