This book contains the proceedings of the 43rd University of Nottingham Feed Conference. The Ruminant section provides tools for reducing the environmental impact of cattle systems by reducing wastage and improving nutritional efficiency. The first chapter reviews the effects of fatty acids on fertility, and the second identifies the major causes of losses during heifer rearing. The third chapter demonstrates the scope for reducing phosphorus inputs and subsequent outputs. The fourth chapter provides practical information on grazing systems and the fifth discusses current feed evaluation systems. Two chapters of the General section also address environmental issues. The first highlights the ways in which livestock production systems might need to adapt to climate change. The second reviews legislation that impacts on pollution and welfare in animal systems. The third chapter reviews methods to reduce mycotoxins in animal feed, which is essential for maintaining food security. The fourth chapter explains the interactions between nutrition, stress and the immune system. The final chapter in the General section provides an update on current and future developments in GM technology.The non-ruminant section concentrates mainly on pig nutrition. Specific chapters consider nutritional implications of feed processing technology, piglet starter diets, organic acids, and amino acids. The final chapter in the non-ruminant section reviews factors that affect pork quality. All chapters are written by international experts and provide comprehensive analyses of issues alongside practical applications. This book is essential reading for anyone involved in the livestock industry, including nutritionists, feed suppliers, researchers, consultants, animal science students, legislators and veterinary practitioners.