The cows that could help fight climate change

A hefty slice of global greenhouse gas emissions come from the smelly bodily functions of livestock. Can tinkering with the microbes in their guts help to save the planet from climate change?


By Geoff Watts, BBC (UK) 

7 August 2019


The cows grazing peacefully in the vicinity of New Zealand’s farming science research institute AgResearch look much like any other. They plod slowly around the pastures, heads bowed as they tear up mouthfuls of grass and let out soft, low moos.


But some of these animals are not like the cattle you might find on other farms. Away from view, inside the hard-working stomachs of these cows, an experiment that could potentially change the planet is taking place.


They have been given a vaccine against certain gut microbes that are responsible for producing methane as the animals digest their food. Methane is one of the most egregious of greenhouse gases, roughly 25 times more potent at trapping heat than carbon dioxide.


AgResearch’s aim is to develop this vaccine, along with other anti-methane methods, in an effort to allow us to continue eating meat and dairy products while lessening the impact the livestock industry has on the environment. Beef without blame, you might say; and cheese with a clear conscience.


Estimates vary, but livestock is reckoned to be responsible for up to 14% of all greenhouse emissions from human activities. Alongside carbon dioxide, farming generates two other gases in large quantities: nitrous oxide from the addition of fertilisers and wastes to the soil, and methane. The latter is largely belched out by ruminants – principally sheep and cattle – and accounts for more than a third of the total emissions from agriculture. The average ruminant produces 250-500 litres of methane a day. Globally, livestock are responsible for burping (and a small amount from farting) the methane equivalent of 3.1 gigatonnes of carbon dioxide into the atmosphere annually.


But the scientists at AgResearch hope it may be possible to reduce the contribution livestock farming is making to global warming...