Authoritative resource on the nutritional management of horses, now incorporating the iterative learning process
The second edition of Equine Clinical Nutrition is a fully updated and expanded revision of the classic student text on nutritional management of horses, covering updated nutrient recommendations, rations, feeding management, clinical nutrition and many other important topics in the field. To aid in reader comprehension, this new edition takes a new instructional approach to nutritional management using an iterative sequence of defined procedures.
Divided into distinct sections for easy accessibility, this book is a comprehensive resource for feeding practices and management of healthy and sick horses alike. A thorough understanding of life stages, anatomy, physiology, and behavior underpins the practice of clinical nutrition.
Sample topics covered in Equine Clinical Nutrition include: - The evolution of horses to changing food supply, the importance of their microbiome, and the behavior patterns of feeding and drinking - Nutrient metabolism of water, energy, protein, minerals, and vitamins, plus ration assessment, farm investigations, forages, and toxic plants - Manufactured feeds, dietary supplements, USA feed regulations, and feed safety protocols - Nutritional assessment of horses by life stage, recognizing pain and discomfort behaviors, and dietary management of weight and major system disorders
Equine Clinical Nutrition is an essential text for students of veterinary medicine, animal science, pre-veterinary programs, and a desk reference for equine practitioners wanting practical clinical feeding recommendations. With comprehensive coverage of the topic, it is an essential text for everything related to nutrition in horses.
Table of Contents
Contributors xvi
Preface xix
Section I The Horse 1
Animal Assessment 3
1 Feeding Horses: Back to Evolution 5
Rebecca L. Remillard
1.1 Introduction 5
1.2 The Evolution of Equus 6
1.2.1 Environmental Changes 6
1.2.2 Musculoskeletal System Changes in Response to Predation on the Open Plains 7
1.2.3 Alimentary System Changes in Response to a Changing Food Supply 8
1.3 Equine Nutrient Requirements vs. Recommendations 10
References 13
2 Nutritional Assessment of the Horse 15
Shannon Pratt Phillips and Meri Stratton- Phelps
2.1 Introduction 15
2.2 Obtaining a History 16
2.3 Physical Examination 16
2.3.1 Determining Body Weight 17
2.3.2 Estimating Body Composition 19
2.3.3 Body Condition Scoring 21
2.4 Changes in Body Weight 22
2.4.1 Etiology of Weight Loss 24
2.4.2 Weight Gain in Adult Horses 26
2.5 Laboratory Tests 26
2.5.1 Weight Loss or Low Body Condition Score 26
2.5.2 Weight Gain or High Body Condition Score 27
2.5.3 Mineral and Vitamin Imbalances 27
References 30
3 The Horse: Host 33
Veronique Julliand, Sarah L. Ralston, and Rebecca L. Remillard
3.1 Introduction 33
3.2 Oral Cavity 34
3.3 Stomach 38
3.4 Small Intestine, Pancreas, and Liver 40
3.5 Cecum and Large Colon 43
3.6 Small Colon, Rectum, and Defecation 46
References 47
4 The Horse: Microbiome 51
Veronique Julliand and J. Scott Weese
4.1 Introduction 51
4.2 Microbiota in Adult Healthy Horses 52
4.3 Microbiota in Healthy Foals and Young Horses 54
4.4 The Role of the Microbiota 55
4.4.1 Nourishment 55
4.4.2 Disease 57
4.5 Exogenous Impacts on and Manipulation of the Microbiome 58
4.5.1 Diet 58
4.5.2 Probiotics 59
4.5.3 Prebiotics 60
4.5.4 Drugs 60
4.5.5 Other Factors 61
4.5.6 Fecal Microbial Transplantation 61
4.6 Assessment of the Microbiota and Microbiome 61
4.6.1 Sampling Sites and Types 62
4.6.2 Sample Handling 62
4.6.3 Testing Methods 62
4.7 Summary 63
References 63
Section II The Diet 69
Nutrient Metabolism 71
5 Water 73
Jonathan M. Naylor
5.1 Water as a Nutrient 73
5.2 Body Water Content 74
5.3 Water Requirement 74
5.4 Water Deficiency 76
5.5 Watering Devices 77
5.6 Sources of Water 78
5.7 Water Quality 79
5.8 Water as Habitat for Disease Vectors and Insects 82
References 83
6 Energy 86
Richard Godbee and Robert Coleman
6.1 The Concept of Energy 86
6.2 Dietary Energy 89
6.2.1 Dietary Carbohydrates 89
6.2.2 Dietary Fats 91
6.3 Horse Energy Requirements 93
6.3.1 Cold Weather Care 95
6.3.2 Hot Weather Care 96
References 97
7 Protein 100
Patricia Graham- Thiers
7.1 Function and Composition 100
7.2 Dietary Protein 101
7.2.1 Protein Digestion 101
7.2.2 Protein Quality 102
7.2.3 Ideal Protein 104
7.2.4 Protein Supplements 104
7.2.5 Non- Protein Nitrogen Sources 105
7.2.6 Protein Imbalance 105
7.3 Horse Protein Requirements by Life Stage 106
7.3.1 Maintenance 106
7.3.2 Growth 108
7.3.3 Gestation 108
7.3.4 Lactation 108
7.3.5 Work 109
References 110
8 Minerals 113
Ashley Fowler, Mieke Brummer- Holder, and Laurie A. Lawrence
8.1 Introduction 113
8.2 Macrominerals 114
8.2.1 Calcium 115
8.2.2 Phosphorus 121
8.2.3 Magnesium 122
8.2.4 Sodium, Potassium, and Chlorine 124
8.2.5 Sulfur 126
8.3 Microminerals 127
8.3.1 Selenium 127
8.3.2 Iodine 131
8.3.3 Copper 133
8.3.4 Zinc 135
8.3.5 Iron 136
8.4 Other Minerals of Interest 138
References 140
9 Vitamins 148
Sarah Dodd, Sarah K. Abood, and Jacqueline M. Parr
9.1 Introduction 148
9.1.1 Sources 149
9.1.2 Requirements 149
9.1.3 Deficiencies and Toxicities 151
9.1.4 Summary 153
9.2 Fat- Soluble Vitamins 154
9.2.1 Vitamin A 154
9.2.2 Vitamin d 157
9.2.3 Vitamin E 159
9.2.4 Vitamin K 161
9.3 Water- Soluble Vitamins 163
9.3.1 Thiamine (B1) 163
9.3.2 Riboflavin (B2) 164
9.3.3 Niacin (B3) 165
9.3.4 Pantothenic Acid (B5) and Pyridoxine (B6) 165
9.3.5 Biotin (B7) 166
9.3.6 Folate (B9) 167
9.3.7 Cobalamin (B12) 168
9.3.8 Vitamin c 168
References 169
Ration Assessment 175
10 Ration Assessment and Farm Investigations 177
Rebecca L. Remillard and Sarah L. Ralston
10.1 Introduction 177
10.2 Farm Investigation 177
10.2.1 Animal Assessment 178
10.2.2 Ration Assessment 178
10.2.3 Water 182
10.2.4 Feeding Management Assessment 182
10.3 Ration Analysis 182
10.4 Ration Formulation 186
10.5 Reassessment 187
References 188
11 Forages 190
Bridgett McIntosh
11.1 Introduction 190
11.2 Importance of Forages 190
11.3 Hay 192
11.3.1 Types of Hay 192
11.3.2 Forms of Hay 193
11.3.3 Hay Cuttings 195
11.3.4 Hay Grades and Relative Feed Value 195
11.3.5 Feeding Management of Hay 196
11.4 Pasture 200
11.4.1 Soil Testing and Fertility 201
11.4.2 Forage Selection 202
11.4.3 Nutritional Considerations in Pasture Plant Selection 203
11.4.4 Grazing Management 205
References 209
12 Toxic Plants 212
Bryan Stegelmeier and T. Zane Davis
12.1 Introduction 212
12.2 Plants that Damage Dermal and Epithelial Tissues 213
12.2.1 Skin Photosensitization 213
12.2.2 Mechanical Injuries to Facial and Oral Tissues 218
12.2.3 Inflammation of the Hoof Laminae 218
12.3 Plants that Contain Gastrointestinal Toxins 220
12.4 Plants that Contain Hepatotoxins 223
12.5 Plants Containing Neurotoxins 227
12.6 Plants that Contain Muscle Toxins 235
12.7 Plants that are Toxic to the Urogenital System 238
References 241
13 Manufactured Feeds 244
Erin Perry, Kathleen Crandell, Jeanne van der Veen, and Jesse M. Fenton
13.1 Introduction 244
13.2 Manufacturing Processes 244
13.2.1 Ingredients 245
13.2.2 Ingredient Processing 250
13.3 Palatability and Preference 254
13.4 Quality Control Measures 255
13.5 Package and Label 257
13.6 Equine Marketing Concepts 257
13.6.1 Specific Purpose 257
13.6.2 Price and Ingredients 258
13.6.3 Nutrients 258
13.6.4 Features and Benefits 258
13.7 Calculating Cost of Feeding 259
References 260
14 Dietary Supplements 264
Donna M. Raditic
14.1 Introduction 264
14.2 Regulation of Supplements 264
14.3 Marketing of Supplements 265
14.3.1 Animal Food Additive 265
14.3.2 Dosage Forms 266
14.4 Evidence- Based Medicine 267
14.5 Musculoskeletal Diseases 268
14.6 Gastrointestinal Diseases 270
14.7 Behavior 272
14.8 Respiratory Diseases 272
14.9 Metabolic/Endocrine Diseases 273
References 274
15 USA Feed Regulations and Safety 279
David A. Dzanis
15.1 Introduction 279
15.2 USA Regulatory Oversight 280
15.2.1 Food and Drug Administration Authority 280
15.2.2 State Authority 280
15.3 Basic Label Requirements 281
15.4 Labeling Claims 285
15.5 Special Products 287
15.5.1 Supplements 287
15.5.2 Medicated Feeds/Veterinary- Directed Feeds 287
15.6 Feed Safety 290
15.7 Enforcement 291
15.8 Reporting Problems with Horse Feed Products 292
15.9 Summary 293
References 293
Section III Feeding Management 295
Healthy Horses 297
16 Feeding and Drinking Behaviors 299
Katherine A. Houpt and Rebecca L. Remillard
16.1 Introduction 299
16.2 Feeding Behaviors 299
16.2.1 Time Management 300
16.2.2 Pastured Horse Feeding Behaviors 301
16.2.3 Stabled Horse Feeding Behaviors 302
16.2.4 Food and Water Intake 303
16.2.5 Pica 303
16.3 Drinking Behavior 303
References 304
17 Feeding Adult and Senior Horses 307
Géraldine Blanchard and Nettie R. Liburt
17.1 Introduction 307
17.2 Animal Assessment 308
17.3 Ration Assessment 312
17.4 Feeding Management 317
17.4.1 Maintenance of Weight and Condition 318
17.4.1.1 Bcs >6/ 9 318
17.4.1.2 Bcs < 4/ 9 319
References 320
18 Feeding Athletes and Working Horses 323
Shannon Pratt- Phillips and Jenna Kutzner Mulligan
18.1 Introduction 323
18.2 Animal Assessment 324
18.3 Ration Assessment 329
18.4 Feeding Management 333
18.4.1 Growing Athlete 335
18.4.2 Mature Athlete 335
18.4.3 Feeding Management Based on Workload 336
18.4.4 Feed and Water During Transport 338
18.4.5 Feeding Management for Specific Conditions 340
References 347
19 Feeding Stallions 354
Stewart K. Morgan and Megan Shepherd
19.1 Introduction 354
19.2 Animal Assessment 354
19.3 Ration Assessment 356
19.4 Feeding Management 359
References 361
20 Feeding Broodmares 364
Stewart K. Morgan and Megan Shepherd
20.1 Introduction 364
20.2 Animal Assessment 365
20.3 Ration Assessment 368
20.4 Feeding Management 372
20.4.1 Gestation 373
20.4.2 Lactation 374
20.4.3 BCS for Reproductive Efficiency 374
References 376
21 Feeding Growing Horses 381
Stewart K. Morgan and Megan Shepherd
21.1 Introduction 381
21.2 Animal Assessment 381
21.3 Ration Assessment 383
21.4 Feeding Management 388
21.4.1 Neonate 388
21.4.2 Suckling Foal 389
21.4.3 Weanling 391
21.4.4 Yearling 392
21.4.5 Two- to Five- Year- Olds 392
References 393
Clinical Nutrition 399
22 Pain and Discomfort Behaviors 401
Katherine A. Houpt
22.1 Introduction 401
22.2 Assessments of Discomfort, Pain, Depression, and Distress 401
22.2.1 Physical Assessments 401
22.2.2 Behavioral Assessments 402
22.3 Freedom from Thirst, Hunger, and Malnutrition 403
22.4 Freedom from Thermal and Physical Discomfort 405
22.5 Freedom from Pain, Injury, and Disease 405
22.6 Freedom from Fear and Distress 407
22.7 Freedom to Express Normal Behaviors 409
References 409
23 Weight Management 411
Shannon P. Phillips and Rebecca L. Remillard
23.1 The Healthy Weight as a Concept 411
23.2 Feeding for Weight Loss 414
23.2.1 Animal Assessment 414
23.2.2 Ration Assessment 416
23.2.3 Feeding Management 417
23.3 Feeding for Weight Gain 421
23.3.1 Animal Assessment 421
23.3.2 Ration Assessment 422
23.3.3 Feeding Management 423
References 425
24 Refeeding and Assisted Feeding of Horses 429
Meri Stratton- Phelps and Rebecca L. Remillard
24.1 Introduction 429
24.2 Feed Reintroduction to Chronically Starved Horses 432
24.2.1 Animal Assessment 432
24.2.2 Ration Assessment 434
24.2.3 Feeding Management 436
24.3 Assisted Feeding 438
24.3.1 Animal Assessment 438
24.3.2 Ration Assessment 439
24.3.3 Feeding Management 443
24.3.3.1 Adult Horses 443
24.3.3.2 Foals 448
References 452
25 Musculoskeletal System Disorders 455
Sarah Dodd and Géraldine Blanchard
25.1 Muscle Disorders 455
25.1.1 Animal Assessment 455
25.1.2 Ration Assessment 457
25.1.3 Feeding Management 457
25.2 Developmental Orthopedic Disease 457
25.2.1 Animal Assessment 458
25.2.2 Ration Assessment 458
25.2.3 Feeding Management 460
25.2.4 Summary 461
25.3 Osteoarthritis 461
25.3.1 Animal Assessment 461
25.3.2 Ration Assessment 461
25.3.3 Feeding Management 462
25.4 Laminitis 462
25.4.1 Animal Assessment 462
25.4.2 Ration Assessment 462
25.4.3 Feeding Management 463
References 464
26 Digestive System Disorders 468
Nicolás C. Galinelli, Andy E. Durham, and Rebecca L. Remillard
26.1 Introduction 468
26.2 Oral Disorders 468
26.3 Esophageal Obstruction 469
26.4 Stomach 470
26.4.1 Ulcers 470
26.4.2 Impaction 472
26.5 Intestines 473
26.5.1 Colic 473
26.5.2 Diarrhea 476
References 479
27 Endocrine System Disorders 483
Nicholas Frank, Elizabeth M. Tadros, and Rebecca L. Remillard
27.1 Insulin Dysregulation 483
27.1.1 Introduction 483
27.1.2 Animal Assessment 487
27.1.3 Ration Assessment 489
27.1.4 Feeding Management 490
27.2 Pituitary Pars Intermedia Dysfunction 490
27.2.1 Animal Assessment 491
27.2.2 Ration Assessment 492
27.2.3 Feeding Management 493
27.3 Hyperlipemia 493
27.3.1 Introduction 493
27.3.2 Animal Assessment 494
27.3.3 Ration Assessment 495
27.3.4 Feeding Management 495
References 497
28 Metabolic Syndrome 501
Patricia Harris and Simon R. Bailey
28.1 Defining Equine Metabolic Syndrome (EMS) 501
28.2 Animal Assessment 502
28.2.1 Obesity 502
28.2.2 Insulin Dysregulation 503
28.3 Ration Assessment 503
28.3.1 Grain Concentrates 503
28.3.2 Forages 503
28.3.3 Complementary Feeds 504
28.4 Feeding Management 504
References 507
Appendix 510
A: Case in Point Answers and Outcomes 510
B: Nutrition Resources 524
C: Nutrition Competencies of Equine Veterinarians 524
D: Feed Glossary 525
E: Average body weight and heights of horses 533
F: Abbreviations 534
Index 536
