There have been some major changes in ruminant production systems in recent years, following increased globalisation of markets for animals and their products. Particularly noticeable, have been the increased genetic merit of dairy cows in many countries and the demand for closer control of quality. These changes have necessitated major reconsideration of nutrient supply and responses to nutrients in terms of milk composition, health and fertility, all of which are addressed in this book. The chapters of this book have all been previously published in Recent Advances in Animal Nutrition, which is the annual proceedings of the University of Nottingham Feed Manufacturers Conference. This book provides a convenient reference source on ruminant nutrition that will be valuable to students, teachers, research workers, advisory staff, farmers and many others.