Dairy production can be improved by increasing feed intake without negatively affecting animal health and well-being. This requires a thorough understanding of intake mechanisms and rumen health. In intensive production systems the right balance between fermentable (starch and sugars) and fibrous carbohydrates (effective fiber) is critical to maintain a healthy rumen. When this balance is altered not also rumen fermentation is modified, but also the motility of the pre-stomachs. This can result in higher incidence of acidosis and displaced abomasum, among other metabolic problems.