Methane emissions – cow burps, not farts

It’s a misunderstanding that methane¹ emissions come from the back end of cows. Fortunately, they are burped out, which means we can target the start of the digestive system² to find ways to reduce emissions. The DairyNZ experts in this video are researching how forages like plantain may help reduce the amount of methane in cow burps.

Question for discussion:

• What causes cows to produce methane?

Transcript

Holly Flay

Methane is an incredibly important gas that’s playing a role in global warming, and we need to play our part in the dairy industry to help reduce those emissions. Methane is one of the byproducts³ of cow digestion⁴. It largely is burped out. There’s minimal amounts of microbial⁵ fermentation⁶ that happens in the large intestines as well, which means they fart out a very minimal amount of methane. But most of it comes out the front end. So it’s cow burps, not cow farts.

Dr Elena Minnée

Their first stomach⁷ – their amazing rumen⁸, which we do not have – is a big fermentation vat of microbes that are busy bubbling away, fermenting away like your ginger beer. And that produces methane gas, and that gas is burped out of there.

Kieran McCahon

So, it’s really important that the vast majority or methane comes from the cow out the mouth – whether that’s through breathing or through belching – through the rumination process. That means we’ve got an incredible solution to be able to influence the rumination process – the rumen microbiology⁹ – to reduce the amount of methane that is ultimately belched out by the cow.

Acknowledgements
Holly Flay
Dr Elena Minnée
Kieran McCahon
DairyNZ