Anatomy and Physiology of Domestic Animals Second Edition Anatomy and Physiology of Domestic Animals Second Edition R. Michael Akers D. Michael Denbow This edition first published 2013 © 2013 by John Wiley & Sons, Inc. First edition 2008 © Blackwell Publishing Editorial offices: 2121 State Avenue, Ames, Iowa 50014-8300, USA The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK 9600 Garsington Road, Oxford, OX4 2DQ, UK For details of our global editorial offices, for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com/wiley-blackwell. Authorization to photocopy items for internal or personal use, or the internal or personal use of specific clients, is granted by Blackwell Publishing, provided that the base fee is paid directly to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923. 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ISBN 978-1-118-35638-8 (cloth : alk. paper) – ISBN 978-1-118-68858-8 – ISBN 978-1-118-68860-1 (ePub) – ISBN 978-1-118-68861-8 (eMobi) – ISBN 978-1-118-68862-5 – ISBN 978-1-118-68866-3 (ePdf) I. Denbow, D. Michael, author. II. Title. [DNLM: 1. Anatomy, Veterinary. 2. Animals, Domestic–physiology. 3. Physiology. SF 761] SF761 636.089′2–dc23 2013017935 A catalogue record for this book is available from the British Library. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Cover image: Goats © Andyworks; Pigs © NeilyImagery; Chickens © johnnyscriv; Cows © ictor Cover design by Nicole Teut Set in 10/12 pt Palatino by Toppan Best-set Premedia Limited 1 2013 Contents Preface vii Chapter 9. Central Nervous System 241 Preface to the First Edition ix Chapter 10. Peripheral and Autonomic About the Companion Website xi Nervous System 265 Chapter 11. Special Senses 297 Chapter 1. Introduction to Anatomy Chapter 12. Endocrine System 323 and Physiology 3 Chapter 13. Cardiovascular System 375 Chapter 2. The Cell: The Common Chapter 14. Respiratory System 417 Physiological Denominator 11 Chapter 15. Immunity 441 Chapter 3. Fundamental Biochemical Chapter 16. Urinary System 459 Pathways and Processes in Chapter 17. Digestive System 483 Cellular Physiology 57 Chapter 18. Lactation 529 Chapter 4. Tissue Structure and Organization 85 Chapter 19. Reproduction 557 Chapter 5. Integumentary System 121 Chapter 6. Bones and Skeletal System 139 Glossary 591 Chapter 7. Muscular Tissue 179 Index 633 Chapter 8. Introduction to the Nervous System 215 v Preface As we originally concluded, the study of physiology agricultural and biological sciences to be successful in goes hand-in-hand with consideration of anatomy at upper-level specialty courses such as nutrition, repro- multiple levels. While the fundamental focus of this duction, lactation, growth biology, biotechnology, and text is physiology, we have strived to include suffi- the like. We also anticipate that this text will provide cient system, organ, tissue, and cellular anatomy for new graduate students with a readily understandable students to better appreciate the integration of both source for review of basic principles. topics. In short, structure and function are inti- We would like to thank our wives (Cathy Akers, 43 mately interconnected. Our book is rich with illustra- years and counting; Dr. Cindy Denbow) for their love, tions that we believe add interest and enhance support, and understanding through these long hours understanding. of figure making, writing, and editing. We would also Moreover, we have made all of these illustrations like to thank our graduate students, colleagues, and available to instructors who adopt the book for use in students in our classes for the inspiration, a helping their classes. We have also increased the use of textbox hand, and lots of questions. We would like to espe- highlights to provide examples to compel student cially thank Ms. Sara Robinson for preparing several interest and inquiry. Chapter summaries and sample drawings and Drs. Anthony Capuco, Steve Ellis, Frank questions for both the student and instructor, as well Gwazdauskas, Ray Nebel, and Frank Robinson, and as specific websites for each, will increase the utility Mrs. Cathy Parsons for photographs used in the text. of the text as well. As before, our overriding goal with this edition is R. Michael Akers to provide foundations for undergraduate students in D. Michael Denbow vii