Equine

Jean-Pierre Lavoie, DVM, DACVIM, is a full professor in Equine Internal Medicine and Associate Dean of Research at the Facult de M decine V t rinaire at the University of Montreal in St-Hyacinthe, Quebec, Canada and an adjunct professor at the Department of Medicine at McGill University in Montreal, Quebec, Canada.

Table of contents

Abdominal Distention in the Adult Horse 1

Abdominal Hernia in Adult Horses* 4

Abdominocentesis—Increased Peritoneal Fluid 5

Abnormal Estrus Intervals 7

Abnormal Scrotal Enlargement 9

Abnormal Testicular Size 11

Abortion, Spontaneous, Infectious 13

Abortion, Spontaneous, Noninfectious 16

Acer rubrum (Red Maple) Toxicosis 19

Acidosis, Metabolic 20

Acidosis, Respiratory 22

Actinobacillosis 24

Acute Adult Abdominal Pain—Acute Colic 25

Acute Epiglottiditis 27

Acute Hepatitis in Adult Horses (Theiler Disease)* 28

Acute Kidney Injury (AKI) and Acute Renal Failure (ARF) 30

Acute-Phase Response 32

Adenovirus 33

Adrenal Insufficiency* 34

Aflatoxicosis 35

African Horse Sickness 36

Agalactia/Hypogalactia 37

Aggression 39

Alkaline Phosphatase (ALP) 42

Alkalosis, Metabolic 44

Alkalosis, Respiratory 45

Alopecia 46

Amitraz Toxicosis 49

Ammonia, Hyperammonemia 50

Amylase, Lipase, and Trypsin 52

Anaerobic Bacterial Infections 53

Anaphylaxis 55

Anemia 57

Anemia, Chronic Disease 59

Anemia, Heinz Body 60

Anemia, Immune Mediated* 62

Anemia, Iron Deficiency 64

Anestrus 65

Angular Limb Deformity 67

Anhidrosis 69

Anorexia and Decreased Food Intake* 70

Anthrax 72

Anticoagulant Rodenticide Toxicosis 73

Anuria/Oliguria 74

Aortic Regurgitation 76

Aortic Rupture 78

Aortoiliac Thrombosis 81

Arsenic Toxicosis 82

Artificial Insemination 83

Arytenoid Chondropathy 86

Ascarid Infestation 88

Aspartate Aminotransferase (AST) 89

Aspiration Pneumonia 91

Atheroma of the False Nostril 92

Atopic Dermatitis* 93

Atrial Fibrillation 96

Atrial Septal Defect 99

Atypical Myopathy 101

Aural Plaques 102

Azotemia and Uremia 103

Back Pain 105

Bacteremia/Sepsis 106

Bacterial Dermatitis—Methicillin-Resistant Staphylococci 108

Bile Acids 110

Bilirubin (Hyperbilirubinemia) 111

Biosecurity, Disinfectants in the Breeding Shed 113

Blood and Plasma Transfusion Reactions 115

Blood Culture 117

Blue-Green Algae 119

Bordetella bronchiseptica 120

Botulism 121

Bradyarrhythmias 123

Broad Ligament Hematoma 124

Brucellosis 125

Bruxism 126

Burdock Pappus Bristle Keratopathy 128

Calcific Band Keratopathy 129

Calcium, Hypercalcemia 130

Calcium, Hypocalcemia 132

Cantharidin Toxicosis 134

Cardiotoxic Plants 136

Castration, Henderson Castration Instrument 138

Castration, Routine 139

Centaurea and Acroptilon Toxicosis 140

Cerebellar Abiotrophy 141

Cervical Lesions 142

Cervical Vertebral Malformation 145

Cestrum diurnum Toxicosis* 146

Chloride, Hyperchloremia 147

Chloride, Hypochloremia 148

Cholelithiasis* 149

Chorioretinitis 150

Chronic Diarrhea* 151

Chronic Kidney Disease 153

Chronic Progressive Lymphedema 155

Chronic Weight Loss 156

Cleft Palate 157

Clitoral Enlargement 158

Clostridial Myositis 159

Clostridium difficile Infection 161

Coagulation Defects, Acquired 163

Coagulation Defects, Inherited 165

Coccidioidomycosis* 166

Coccidiosis 167

Colic, Chronic/Recurrent 168

Colic in Foals 170

Complex Congenital Cardiac Disease 173

Conception Failure in Mares 175

Congenital Cardiac Abnormalities* 178

Conium maculatum (Poison Hemlock) Toxicosis 180

Conjunctival Diseases 181

Contagious Equine Metritis (CEM) 183

Corneal/Scleral Lacerations 185

Corneal Stromal Abscesses 186

Corneal Ulceration 187

Corynebacterium pseudotuberculosis* 189

Cough, Acute/Chronic 191

Creatine Kinase (CK) 193

Cryptorchidism 195

Cryptosporidiosis 197

Cutaneous Photosensitization* 198

Cyanide Toxicosis 200

Cyathostominosis* 201

Cytology of Bronchoalveolar Lavage (BAL) Fluid 203

Cytology of Pleural Fluid 204

Cytology of Tracheal Aspiration (TA) Fluid 205

Dacryocystitis 207

Delayed Uterine Involution 209

Dermatomycoses, Subcutaneous (SC) 210

Dermatomycoses, Superficial 213

Dermatophilosis 215

Diaphragmatic Hernia 216

Diarrhea, Neonate 217

Dicoumarol (Moldy Sweet Clover) Toxicosis 219

Diseases of the Equine Nictitans 220

Disorders of Sexual Development 222

Disorders of the Thyroid, Hypo- and Hyperthyroidism 224

Disseminated Intravascular Coagulation 226

Distal and Proximal Interphalangeal Joint Disease 228

Distal Tarsitis 229

Dorsal Displacement of the Soft Palate (DDSP) 230

Dorsal Metacarpal Bone Disease 231

Dourine 232

Duodenitis–Proximal Jejunitis (Anterior Enteritis, Proximal Enteritis) 234

Dynamic Collapse of the Upper Airways 236

Dystocia 238

Ear Tick-Associated Muscle Cramping 240

Early Embryonic Death 241

Eastern (EEE), Western (WEE), and Venezuelan (VEE) Equine Encephalitides 243

Eclampsia 245

Ectoparasites 246

Embryo Transfer 248

Endocarditis, Infective 250

Endometrial Biopsy 252

Endometritis 254

Endotoxemia 258

Enterolithiasis 260

Eosinophilia and Basophilia 262

Eosinophilic Enteritis 263

Eosinophilic Keratitis 265

Epiglottic Entrapment 266

Equine Asthma 267

Equine Coronavirus* 268

Equine Granulocytic Anaplasmosis 269

Equine Herpesvirus 5 271

Equine Herpesvirus Myeloencephalopathy 272

Equine Metabolic Syndrome (EMS)/Insulin Dysregulation (ID) 273

Equine Motor Neuron Disease 275

Equine Odontoclastic Tooth Resorption and Hypercementosis 277

Equine Oocytes and Intracytoplasmic Sperm Injection (ICSI)* 279

Equine Protozoal Myeloencephalitis (EPM) 281

Equine Recurrent Uveitis 284

Equine Sarcoidosis 286

Esophageal Obstruction (Choke) 287

Excessive Maternal Behavior/Foal Stealing 289

Exercise-Associated Arrhythmias 290

Exercise-Induced Pulmonary Hemorrhage (EIPH)* 291

Exercise Intolerance in Sport Horses 292

Exertional Rhabdomyolysis 294

Expiratory Dyspnea 296

Exudative Optic Neuropathy 298

Eyelid Diseases 299

Failure of Transfer of Passive Immunity (FTPI) 301

Fear 303

Fescue Toxicosis 306

Fetal Stress/Distress/Viability 308

Fever 311

Flexural Limb Deformity 315

Fluid Therapy, Neonate 317

Foal Immunodeficiency Syndrome 319

Fractures in Endurance Horses 320

Fumonisins* 322

Fungal Pneumonia 324

Fusaria* 325

Gamma-Glutamyltransferase (GGT) 326

Gastric Dilation/Distention 328

Gastric Impaction 330

Gastric Neoplasia 332

Gastric Ulcers and Erosions (Equine Gastric Ulcer Syndrome, EGUS) 333

Gastric Ulcers, Neonate 335

Getah Virus Infection* 337

Glanders* 338

Glaucoma 339

Glucose, Hyperglycemia 341

Glucose, Hypoglycemia 343

Glucose Tolerance Tests 344

Glycogen Branching Enzyme Deficiency 346

Goiter 347

Granulomatous Enteritis 348

Grass Sickness* 349

Guttural Pouch Empyema 351

Guttural Pouch Mycosis 352

Guttural Pouch Tympany 353

Headshaking 354

Head Trauma 355

Heaves (Severe Equine Asthma, RAO) 357

Hemangiosarcoma 359

Hemorrhage, Acute 360

Hemorrhage, Chronic 362

Hemorrhagic Nasal Discharge 363

Hemospermia 364

Hendra Virus 365

Hepatic Abscess and Septic Cholangiohepatitis 366

Hepatic Encephalopathy 368

Hereditary Equine Regional Dermal Asthenia 369

Hernias (Umbilical and Inguinal) 370

Herpesvirus 3 372

Herpesvirus Types 1 and 4 373

High-Risk Pregnancy 375

Hydrocephalus 379

Hydrops Allantois/Amnion 380

Hyperkalemic Periodic Paralysis 382

Hyperlipidemia/Hyperlipemia 384

Hyperthermia* 386

Hypoxemia 388

Icterus (Prehepatic, Hepatic, Posthepatic) 390

Idiopathic Colitis/Typhlitis* 392

Ileal Hypertrophy 394

Ileus 395

Immune-Mediated Keratitis 397

Immunoglobulin Deficiencies 399

Immunosuppression 401

Impaction 403

Infectious Anemia (EIA) 405

Infectious Arthritis (Nonhematogenous) 407

Inflammatory Airway Disease—IAD in Performing Horses (Mild and Moderate Equine Asthma) 409

Influenza* 411

Insect Hypersensitivity 413

Inspiratory Dyspnea 415

Insulin Levels/Insulin Tolerance Test 417

Internal Abdominal Abscesses 419

Intestinal Absorption Tests 421

Intra-abdominal Hemorrhage in Horses* 423

Intracarotid Injections 425

Ionophore Toxicosis 426

Iris Prolapse 428

Iron Toxicosis 429

Ischemic Optic Neuropathy 430

Isocoma pluriflora Toxicosis* 431

Juglans nigra (Black Walnut) Toxicosis 432

Laminitis 433

Lantana camara Toxicosis* 436

Large Colon Torsion* 437

Large Ovary Syndrome 439

Laryngeal Hemiparesis/Hemiplegia (Recurrent Laryngeal Neuropathy) 442

Lavender Foal Syndrome 444

Lawsonia Intracellularis Infections in Foals 445

Lead (Pb) Toxicosis 446

Learning, Training, and Behavior Problems 448

Lens Opacities/Cataracts 451

Leptospirosis 453

Lethal White Foal Syndrome 455

Leukocytoclastic Pastern Vasculitis 456

Leukoencephalomalacia 458

Locomotor Stereotypic Behaviors 460

Lungworm—Parasitic Bronchitis and Pneumonia 462

Lyme Disease 463

Lymphadenopathy 465

Lymphocytic–Plasmacytic Enterocolitis 466

Lymphocytosis 467

Lymphopenia 469

Lymphosarcoma 470

Magnesium (Mg2+) 472

Magnesium Disorders* 473

Malabsorption 474

Malicious Intoxication 476

Mastitis 477

Maternal Foal Rejection 478

Meconium Retention 479

Melanoma* 481

Melena and Hematochezia 482

Meningitis, Neonate 483

Mercury Toxicosis 484

Metabolic Disorders in Endurance Horses 485

Metacarpo- (Metatarso-)phalangeal Joint Disease 487

Metaldehyde Toxicosis 488

Methemoglobin 489

Methylxanthine Toxicosis 491

Mitral Regurgitation 492

Monensin Toxicosis 494

Monocytosis 495

Multiple Endocrine Neoplasia Syndrome 496

Multiple Myeloma 497

Multisystemic Eosinophilic Epitheliotropic Disease* 498

Myeloproliferative Diseases 499

Myocardial Disease 500

Narcolepsy and Cataplexy 502

Navicular Syndrome 503

Neonatal Isoerythrolysis 504

Neonatal Maladjustment Syndrome 506

Nerium oleander (Oleander) Toxicosis 508

Neuroaxonal Dystrophy/Equine Degenerative Myeloencephalopathy 509

Neutropenia 510

Neutrophilia 512

Nigropallidal Encephalomalacia 514

Nitrate/Nitrite Toxicosis 515

Nutrition in Foals* 516

Nutritional Myodegeneration 518

Nutritional Secondary Hyperparathyroidism (NSHPT) 520

Ocular/Adnexal Squamous Cell Carcinoma 521

Ocular Examination 523

Ocular Problems in the Neonate 524

Omphalophlebitis 526

Optic Nerve Atrophy 528

Oral Neoplasia 529

Oral Stereotypic Behavior 531

Oral Ulcers 533

Orbital Disease 535

Organophosphate and Carbamate Toxicosis 537

Osmolality, Hyperosmolality 539

Osteoarthritis 541

Osteochondrosis 543

Ovulation Failure 545

Pancreatic Disease 546

Pancytopenia 547

Panicum coloratum (Kleingrass) Toxicosis* 548

Papillomatosis 549

Paraphimosis 550

Pastern Dermatitis 552

Patent Ductus Arteriosus 554

Patent Urachus 556

Pemphigus Foliaceus 557

Penetrating Injuries to the Foot* 558

Penile Lacerations 559

Penile Paralysis 560

Penile Vesicles, Erosions, and Tumors 561

Pentachlorophenol (PCP) Toxicosis 563

Pericarditis 564

Perineal Lacerations/Recto-Vaginal-Vestibular Fistulas 566

Periocular Sarcoid 568

Periodontal Disease 570

Peritonitis 572

Petechiae, Ecchymoses, and Hematomas 573

Pharyngeal Lymphoid Hyperplasia (Pharyngitis) 574

Pheochromocytoma 575

Phimosis 576

Phosphorus, Hyperphosphatemia 577

Phosphorus, Hypophosphatemia 578

Photic Headshaking 579

Photosensitization* 581

Pica 583

Pigmenturia (Hematuria, Hemoglobinuria, and Myoglobinuria) 584

Piroplasmosis 587

Pituitary Pars Intermedia Dysfunction 589

Placenta Basics 591

Placental Insufficiency 592

Placentitis 593

Plasma Proteins 595

Pleuropneumonia 597

Pneumonia, Neonate 598

Pneumothorax 600

Pneumovagina/Pneumouterus 601

Poisoning (Intoxication)—General Principles 602

Polycythemia 605

Polyneuritis Equi 607

Polysaccharide Storage Myopathy 608

Polyuria (PU) and Polydipsia (PD) 609

Postpartum Metritis 611

Potassium, Hyperkalemia 613

Potassium, Hypokalemia 614

Potomac Horse Fever (PHF) 615

Pregnancy Diagnosis 617

Premature Placental Separation 620

Prematurity/Dysmaturity in Foals 621

Prepubic Tendon Rupture 623

Priapism 624

Primary Hyperparathyroidism 625

Probiotics in Foals and Horses* 626

Progressive Ethmoidal Hematoma (PEH)* 628

Proliferative Optic Neuropathy 629

Prolonged Diestrus 630

Prolonged Pregnancy 632

Protein, Hyperproteinemia 634

Protein, Hypoproteinemia 636

Protein-Losing Enteropathy (PLE) 638

Ptyalism 639

Purpura Haemorrhagica 640

Purulent Nasal Discharge 642

Pyometra 644

Pyrrolizidine Alkaloid Toxicosis* 646

Quercus spp. (Oak) Toxicosis 648

Rabies 649

Rectal Prolapse 650

Rectal Tears 652

Regurgitation/Vomiting/Dysphagia 654

Removal and Shipment of Ovaries for Postmortem ICSI 655

Respiratory Distress Syndrome in Foals 657

Resuscitation, Neonate 658

Retained Deciduous Teeth 660

Retained Fetal Membranes 662

Rhodococcus equi (Prescottella equi) 663

Rib Fractures in Foals 665

Right and Left Dorsal Displacement of the Colon 666

Right Dorsal Colitis 668

Robinia pseudoacacia (Black Locust) Toxicosis 670

Rotavirus 671

Salmonellosis 672

Sand Impaction and Enteropathy 674

Sarcoid* 676

Seasonal Pasture Myopathy/Atypical Myopathy 678

Seizure Disorders 679

Seizures in Foals* 680

Selenium Intoxication 682

Self-Mutilation 683

Septic Arthritis, Neonate 684

Septic Meningoencephalomyelitis 686

Septicemia, Neonate 687

Serum Amyloid A (SAA) 689

Severe Combined Immunodeficiency 691

Shivers (Shivering) 692

Sinusitis (Paranasal)* 693

Slaframine Toxicosis 695

Small Intestinal Obstruction 696

Smoke Inhalation 699

Snake Envenomation 701

Sodium, Hypernatremia 703

Sodium, Hyponatremia 704

Solanum spp. (Nightshade) Toxicosis 705

Solar Abscess 706

Soluble Oxalate Toxicosis 707

Sorbitol Dehydrogenase (SDH) 708

Sorghum spp. Toxicosis 710

Spermatogenesis and Factors Affecting Sperm Production 711

Spider Envenomation 713

Splenomegaly 714

Stallion Sexual Behavior Problems 715

Stationary Night Blindness 717

Streptococcus equi Infection 718

Stress Fractures 720

Stringhalt 722

Summer Pasture-Associated Equine Asthma (Pasture Asthma)* 723

Superficial Non-Healing Ulcers 725

Supraventricular Arrhythmias 726

Suspensory Desmitis 728

Synchronous Diaphragmatic Flutter 729

Synovial Fluid 730

Temporohyoid Osteoarthropathy 732

Tendonitis 733

Tenesmus 735

Teratoma 737

Tetanus* 738

Thoracic Trauma 740

Thrombocytopenia 742

Thrombocytosis 744

Thrombophlebitis 745

Thyroid-Releasing Hormone (TRH) and Thyroid-Stimulating Hormone (TSH) Tests 746

Thyroid Tumors 748

Toxic Hepatopathy 749

Tremorgenic Mycotoxin Toxicoses 751

Tricuspid Regurgitation 753

Trifolium hybridum Toxicosis 755

Tropane Alkaloids Toxicosis 756

Trypanosomiasis 757

Tuberculosis 759

Tumors of the Respiratory System 760

Twin Pregnancy 761

Tyzzer Disease (Clostridium piliforme) 763

Ulcerative Keratomycosis 764

Upward Fixation of the Patella 766

Urinalysis (U/A) 767

Urinary Incontinence 769

Urinary Tract Infection (UTI) 771

Urine Pooling/Urovagina 773

Urolithiasis 774

Uroperitoneum, Neonate 776

Urticaria 778

Uterine Inertia 780

Uterine Torsion 781

Vaccination Protocols 783

Vaginal Prolapse 785

Vaginitis and Vaginal Discharge 786

Ventricular Arrhythmias 787

Ventricular Septal Defect (VSD) 790

Verminous Meningoencephalomyelitis 792

Vesicular Stomatitis 793

Vicia villosa (Hairy Vetch) Toxicosis 794

Viral Arteritis (EVA) 795

Viral (Herpes) Keratitis (Putative) 797

Vision 798

Vitrification of Equine Embryos 800

Vulvar Conformation 802

Weaning Separation Stress 804

West Nile Virus 806

Index 807