Cows are methane-making machines, with their inefficient digestion producing hundreds of liters of the greenhouse gas every day. Now scientists are looking at ways to make things go down a little more gently for the ruminanting grass-munchers.

Cows are burping too much methane for the world's good. While people are being asked to reduce the amounts of flights they take and make their homes more energy efficient, what they put on their plates could be having as big an impact on climate change. Gas-guzzling SUVs and badly insulated buildings are partly to blame for the earth's greenhouse gas emissions, but it seems the humble grass-munching cow is also a major culprit.

Agriculture is responsible for producing 37 percent of global methane emissions, a gas that is 23 times more potent than CO2 when it comes to global warming. And much of this gas comes from the burps of ruminating animals such as cows and sheep. If a cow's manners could be improved a bit, then the world might just stop warming quite so fast. And it could be as simple as getting them to graze on different types of plants. Scientists at the University of Aberystwyth are now working on using plant-breeding methods to develop new diets for livestock.