In Holland research of Wageningen University & Research shows that pasturing cows can decrease the methane emission of cows by up to 30 percent compared to cows that get a ration of grass silage. With full pasturing methane emission was 17.2 gram, feeding fresh grass in the barn resulted in a emission of 18.3 gram and feeding grass silage gave an emission of 21.3 gram. With pasturing in spring emission was even 14.5 gram.