This book is intended to provide the reader with an understanding of the principles relating to livestock feeding. Numerous changes have occurred since its last publication with respect to scientific knowledge, world politics, international relations, food security, and many other areas. Many need world markets have opened. There is an increasing challenge to improve production efficiency so that livestock products can compete in these new marketing opportunities. Because the cost of feeding normally accounts for the largest single input in a production operation, there is a need for a better understanding of nutrition and feeding for those that are going to be involved in livestock production. The book provides a brief historical perspective of the development of modern livestock production. The ability to provide a safe, nutritious food supply for the world's population has been the driving force behind the development of modern agriculture in the world, with the well-being of the animals and profitability being major considerations. Many advances in genetics, including the development of transgenic animals, and concern about the environment have impacted livestock producers. It is becoming increasingly important to have a better understanding of the effects that feeding and management of livestock have on livestock production systems and environment. This book will provide the reader with a basic understanding of the nutrition, livestock production systems, and the utilization of feedstuffs. Species chapters will discuss the management and feeding practices that are unique to those species. Feedstuff characteristics and nutrient guidelines are given for various classes of the species in the Appendix Tables. It is our sincere hope that this book will enable the reader to gain knowledge of the principles and management practices used in livestock feeding. A special "thank you" is extended to Professor Tammy May, New Mexico State University, and Dr. Doreen Kinkel, Texas A&M University-Kingsville, for their valuable feedback and suggestions. Richard O. Kellems D.C. ChurchKellems, Richard O. is the author of 'Livestock Feeds and Feeding', published 2001 under ISBN 9780130105820 and ISBN 0130105821.