how much green house gases does a cow produce?

Answer 1

A cow emits a large amount of methane gas in a single day; 95% of this methane is produced through belching, not flatulence. As methane is a potent greenhouse gas (23 times as warming as carbon dioxide), research is underway on dietary supplements that can reduce these releases.

Other mammals, such as cows and sheep also burp; in these cases, the gas expelled is actually methane produced as a byproduct of the animal's digestive process. Anaerobic organisms such as Escherichia coli (E. coli) and methanogenic archaea produce this effect. An average cow is thought to emit between 542 litres (if located in a barn) and 600 litres (if in a field) of methane per day through burping and flatulence, making commercially farmed cattle a major contributor to the greenhouse effect. 95% of this gas is emitted through belching. This has led scientists at the Commonwealth Scientific and Industrial Research Organisation of Perth, Australia, to develop an anti-methanogen vaccine to minimize methane in cattle burps

Answer 2

Not as much as your car.