Mark Lee explains how we might be able to reduce a cow’s methane output by changing its diet
Cows and other ruminant livestock are notorious producers of methane, a potent greenhouse gas much more effective at trapping heat than carbon dioxide.
There is a vicious circle when it comes to cows, methane and plants. The gas is produced by cows as they re-munch on plants, contributing to the warming of our planet. The plants adapt to the hotter conditions by become tougher to digest, requiring more time in the animals’ stomachs. This in turn produces more methane, further warming the planet.
Different plants – even different grasses – vary hugely in terms of chemistry, with contrasting amounts of fibre, protein and sugar. Inside a cow, these chemicals can promote or prevent methane from being burped up. So, yes – it is possible to produce less methane and more milk simply by changing what cows eat. This is what we are researching at Kew.