Methane (CH4) is a greenhouse gas of which the release into the atmosphere is directly linked with animal agriculture, particularly ruminant production. CH4 emissions from ruminant also represent a loss in productive energy for the animal. Development of effective strategies to mitigate these methane emissions will have not only environmental benefits for the planet but also nutritional benefits for the animal. It has been shown that concentrate-rich diets result in a decrease in methanogenesis per unit of animal product (milk, meat). However, some of these diets may have adverse effects on the efficiency of production, e.g. due to risk of acidosis. Our study focused on measuring methane emissions on young bulls fed three contrasting finishing diets characteristics of three intensive levels of production in France.