Scientists are working to beat global warming by stopping cows from burping and farting so much. Cows can produce 500 litres of methane, which is bad for the environment, every day, mostly through burping. Experts in Aberdeen hope an additive in their feed will prevent cows and sheep from making so much of the gas. It could also be good news for farmers, because it’s thought putting out less methane saves energy letting the animals grow more quickly.