Necropsy Guide for Dogs, Cats, and Small Mammals

List of Contributors xv Foreword xvii Acknowledgments xix About the Companion Website xxi Part I Necropsy Fundamentals 1 1 Introduction to the Necropsy 3 Sean P. McDonough and Teresa Southard 1.1 What is a Necropsy? 3 1.2 Why do a Necropsy? 3 1.3 What Information Can and Cannot Be Gained from a Necropsy 3 1.4 When to Refer a Necropsy 4 2 Necropsy Basics 9 Sean P. McDonough and Teresa Southard 2.1 Necropsy Facilities 9 2.2 Necropsy Equipment 9 2.3 Safety Considerations 13 2.3.1 Cuts and Punctures 14 2.3.2 Zoonotic Disease 14 2.3.3 Formalin 15 2.4 The Importance of a Good History 15 2.5 The Necropsy Report 15 2.5.1 Gross Description 15 2.5.2 Gross Findings 16 2.5.3 Gross Diagnosis 16 2.5.4 Comment 16 2.6 Postmortem Changes 16 3 The Necropsy Procedure 21 Sean P. McDonough and Teresa Southard 3.1 Introduction 21 3.2 Weigh the Body 21 3.3 External Examination 21 3.4 Reflect the Skin and Right Limbs 22 3.5 Open the Abdominal Cavity 26 3.6 Puncture the Diaphragm 27 3.7 Open the Thoracic Cavity 27 3.8 Open the Pericardium 28 3.9 In Situ Examination of Organs 29 3.10 Remove the Adrenal Glands 30 3.11 Remove the Pluck 30 3.12 Remove the Gastrointestinal Tract, Liver, and Spleen 32 3.13 Remove the Urogenital Organs 34 3.14 Remove the Head 35 3.15 Take Out the Eyes 35 3.16 Remove the Brain 36 3.17 Remove the Pituitary Gland 37 Bibliography 37 Part II Organ Systems 39 4 The Integumentary System 41 Jeanine Peters-Kennedy 4.1 Anatomy Review 41 4.1.1 External Ear Canal Anatomy 42 4.2 In Situ Examination and Removal 42 4.2.1 Primary Lesions 42 4.2.2 Lesions that May Be Primary or Secondary 43 4.2.3 Secondary Skin Lesions 43 4.3 Organ Examination, Sectioning, and Fixation 44 4.3.1 Cytology 44 4.3.2 Skin Scrapes 44 4.3.3 Hair Examination (Trichogram) 44 4.3.4 Examination of the External Ear Canal 44 4.3.5 Sampling the Skin 45 4.4 Common Artifacts and Postmortem Changes 46 Bibliography 46 5 The Musculoskeletal System 49 Teresa Southard 5.1 Anatomy Review 49 5.1.1 Bones and Joints 49 5.1.2 Teeth 51 5.1.3 Skeletal Muscle 52 5.2 In Situ Evaluation, Sectioning, and Fixation 52 5.2.1 Bones 52 5.2.2 Joints, Tendons, and Ligaments 54 5.2.3 Skeletal Muscle 55 5.3 Special Techniques 55 5.3.1 Postmortem Imaging 55 5.3.2 Cleaning Bones 56 5.3.3 India Ink Evaluation of Articular Cartilage 56 5.3.4 Examining the Intervertebral Discs 56 5.3.5 Submitting Muscle for Additional Tests 56 5.4 Common Artifacts and Postmortem Changes 56 Bibliography 57 6 The Cardiovascular System 59 Kathleen M. Kelly 6.1 Anatomy Review 59 6.1.1 Right Heart 59 6.1.2 Left Heart 60 6.1.3 Vessels: Great and Small 60 6.1.4 Contextual Cardiac Embryology and Congenital Heart Malformations 62 6.2 In Situ Evaluation and Removal 63 6.3 Organ Examination, Sectioning, and Fixation 64 6.4 Common Artifacts, Non-lesions, and Postmortem Changes 66 Bibliography 68 7 The Respiratory System 69 Elizabeth L. Buckles and Teresa Southard 7.1 Anatomy Review 69 7.2 In Situ Evaluation and Removal 71 7.3 Organ Examination, Sectioning, and Fixation 72 7.3.1 Larynx and Trachea 72 7.3.2 Lungs 73 7.3.3 Nasal Cavity and Sinuses 74 7.4 Special Techniques 74 7.5 Common Artifacts and Postmortem Changes 75 Bibliography 75 8 The Alimentary System 77 Gerald E. Duhamel 8.1 Anatomy Review 77 8.1.1 The Oropharyngeal Cavity 77 8.1.2 The Salivary Glands 78 8.1.3 The Esophagus 78 8.1.4 The Stomach 79 8.1.5 The Small Intestine 79 8.1.6 The Large Intestine 81 8.1.7 The Intestinal Vasculature and Nervous System 82 8.2 In Situ Evaluation and Removal 82 8.2.1 The Esophagus 83 8.2.2 The Gastrointestinal Tract 83 8.3 Organ Examination, Sectioning, and Fixation 85 8.3.1 Gastrointestinal Tract 85 8.4 Special Techniques 87 8.5 Common Artifacts and Postmortem Changes 88 Bibliography 89 9 The Liver and Pancreas 91 Sean P. McDonough 9.1 Anatomy Review 91 9.1.1 The Liver 91 9.1.2 The Pancreas 93 9.2 In Situ Evaluation and Removal 94 9.2.1 The Liver 94 9.2.2 The Pancreas 96 9.3 Organ Examination, Sectioning, and Fixation 96 9.3.1 The Liver 96 9.3.2 The Pancreas 98 9.4 Common Artifacts and Postmortem Changes 98 9.4.1 The Liver 98 9.4.2 The Pancreas 99 Bibliography 99 10 The Urogenital System 101 Teresa Southard 10.1 Anatomy Review 101 10.2 In Situ Evaluation and Removal 103 10.3 Organ Examination, Sectioning, and Fixation 103 10.3.1 Kidneys 103 10.3.2 Ureters 104 10.3.3 Bladder and Urethra 104 10.3.4 Ovaries 105 10.3.5 Oviduct/Uterus/Cervix/Vagina 105 10.3.6 Testes/Epididymides/Ductus Deferens 105 10.3.7 Prostate Gland 105 10.3.8 Bulbourethral Gland (Cats Only) 106 10.3.9 Distal Colon/Rectum/Anus 106 10.4 Special Techniques 106 10.5 Common Artifacts and Postmortem Changes 106 Bibliography 106 11 The Nervous System 107 Andrew D. Miller 11.1 Anatomy Review 107 11.2 In Situ Evaluation and Removal 108 11.2.1 Brain 108 11.2.2 Spinal Cord 109 11.2.3 Peripheral Nerves 110 11.3 Organ Examination, Sectioning, and Fixation 110 11.3.1 Brain 110 11.3.2 Spinal Cord 112 11.3.3 Nerves 112 11.4 Common Artifacts and Postmortem Changes 112 Bibliography 113 12 The Eye and Ear 115 Sean P. McDonough 12.1 The Eye 115 12.1.1 Anatomy Review 115 12.1.2 In Situ Evaluation and Removal 115 12.1.3 Examination, Sectioning, and Fixation 117 12.2 The Ear 119 12.2.1 Anatomy Review 119 12.2.2 In Situ Evaluation and Removal 122 12.2.3 Examination, Sectioning, and Fixation 122 Bibliography 123 13 The Endocrine System 125 Sean P. McDonough 13.1 Anatomy Review 125 13.1.1 The Pituitary Gland 125 13.1.2 The Thyroid and Parathyroid Glands 125 13.1.3 The Endocrine Pancreas (Islets of Langerhans) 126 13.1.4 The Adrenal Glands 126 13.2 In Situ Evaluation and Removal 127 13.2.1 The Pituitary Gland 127 13.2.2 The Thyroid and Parathyroid Glands 128 13.2.3 The Endocrine Pancreas 129 13.2.4 The Adrenal Glands 130 13.3 Organ Examination, Sectioning, and Fixation 130 13.3.1 The Pituitary Gland 130 13.3.2 The Thyroid and Parathyroid Glands 131 13.3.3 The Endocrine Pancreas 131 13.3.4 The Adrenal Glands 131 13.4 Common Artifacts and Postmortem Changes 132 14 The Lymphoreticular System 133 Sean P. McDonough 14.1 Anatomy Review 133 14.1.1 Thymus 133 14.1.2 Lymph Nodes 133 14.1.3 Spleen 133 14.1.4 Bone Marrow 135 14.2 In Situ Evaluation and Removal 135 14.2.1 Thymus 135 14.2.2 Lymph Nodes 136 14.2.3 Spleen 136 14.2.4 Bone Marrow 138 14.3 Organ Examination, Sectioning, and Fixation 138 14.3.1 Thymus 138 14.3.2 Lymph Nodes 138 14.3.3 Spleen 140 14.3.4 Bone Marrow 140 14.4 Incidental Findings 141 Part III Special Cases 143 15 Small Mammal Necropsies 145 Teresa Southard 15.1 Species Differences 145 15.2 Necropsy Technique 145 Bibliography 151 16 Fetuses and Neonatal Animals 153 Teresa Southard 16.1 Anatomy 153 16.1.1 Placenta 153 16.1.2 Umbilical Cord 153 16.1.3 Fetal Circulation 153 16.2 Necropsy Technique 154 16.3 Common Artifacts and Postmortem Changes 156 Part IV Additional Testing 157 17 Cytology 159 Teresa Southard 17.1 Types of Cytology Preparations 159 17.2 Making a Touch Imprint 159 17.3 Making a Bone Marrow Smear 159 17.4 Other Preparations 160 17.5 Staining 160 17.6 Atlas of Normal Tissues 161 18 Histopathology 165 Sean P. McDonough and Teresa Southard 18.1 Necropsy Samples for Histopathology 165 18.2 Fixation 165 18.3 Practical Guidelines to Optimize Fixation 168 19 Infectious Disease Testing 171 Teresa Southard 19.1 Test Types 171 19.2 Aerobic Culture 171 19.3 Anaerobic Culture 173 19.4 Fungal Culture 173 19.5 Fluorescent Antibody Tests 174 19.6 PCR 174 19.7 ELISA 174 19.8 Virus Isolation 174 19.9 Qualitative Fecal 174 19.10 Immunohistochemistry 174 20 Toxicology Testing 175 Teresa Southard Bibliography 175 21 Packaging and Shipping Samples 179 Sean P. McDonough 21.1 Packing Samples to Send to the Lab 180 Bibliography 180 Appendix 1: Normal Organ Weights (Percentage Body Weight) 183 Appendix 2: North American Diagnostic Laboratories 187 Appendix 3: Tissue Collection Checklist 193 Appendix 4: Describing Gross Lesions 195 Index 197