Animals fart
 Cattle and sheep fart to produce carbon dioxide, hydrogen sulfide, methane and other gases, which are the natural gas and biogas we usually use. Cattle and sheep mainly feed on grass, but plant fiber is difficult to digest and needs to be chewed constantly. So unlike other animals, they have four stomachs, of which the rumen is a huge storage room, to meet the needs of cattle and sheep to ruminate when they are free after a large amount of food.
 Why do sheep fart
 Every sheep will fart and burp, which can release a lot of methane and carbon dioxide, so the amount of methane gas emitted by tens of millions of sheep is quite huge.
 Through research, scientists found that the total methane emissions from sheep have accounted for 35% of the total methane emissions in New Zealand, which is also the original intention of scientists to cultivate "little fart sheep".