Horse Disorders and Diseases: The Merck Manual for Pet Health

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Horse Disorders and Diseases

Blood Disorders of Horses Heart and Blood Vessel Disorders of Horses

Introduction to Heart and Blood Vessel Disorders of Horses
	Heart Rate
	Heart Sounds and Murmurs
	Arrhythmias
	Pulse
Heart Disease and Heart Failure in Horses
	Abnormalities of the Cardiovascular System
Diagnosis of Cardiovascular Disease in Horses
	General Signs of Cardiovascular Disease
Treatment of Cardiovascular Disease in Horses
	Common Types of Drugs for Cardiovascular Disease
Congenital and Inherited Disorders of the Cardiovascular System in Horses
	Detecting Congenital Heart Defects
	General Treatment and Outlook
	Common Congenital Heart Defects
		Ventricular Septal Defects
		Patent Ductus Arteriosus
		Tetralogy of Fallot
		Tricuspid Dysplasia (Atresia)
Heart Failure in Horses
	Compensatory Mechanisms
	Treatment
Acquired Heart and Blood Vessel Disorders in Horses
	Degenerative Valve Disease
	Myocarditis
	Infective Endocarditis
	Pericardial Disease
	High Blood Pressure (Hypertension)
Blood Clots and Aneurysms in Horses
	Signs and Diagnosis
	Treatment

Digestive Disorders of Horses

Introduction to Digestive Disorders of Horses
	General Signs of Digestive System Disorders
	Examination of the Digestive System
	Infectious Diseases
	Noninfectious Diseases
	Treatment Overview of Digestive System Disorders
		Treatment and Control of Infectious Disease
Congenital and Inherited Disorders of the Digestive System in Horses
	Mouth
	Teeth
	Cysts of the Head and Neck
	Hernias
	Stomach
	Small and Large Intestine
	Liver
Dental Development of Horses
	Estimation of Age by Examination of the Teeth
Dental Disorders of Horses
	Signs of Dental Problems
	Dental Examination and Preventive Care
	Birth Defects and Developmental Abnormalities
		Abnormal Tooth Eruption
		Irregular Tooth Wear (Enamel Points )
		Wave Mouth and Step Mouth
	Gum Disease
	Tooth Decay
Disorders of the Mouth in Horses
	Lip Lacerations
	Paralysis of the Tongue
	Oral Tumors
	Slaframine Poisoning
	Inflammation of the Mouth (Stomatitis)
	Papillar Stomatitis
Pharyngeal Paralysis in Horses
Disorders of the Esophagus in Horses
	Obstruction of the Esophagus (Choke)
	Esophageal Strictures (Narrowing)
Stomach (Gastric) Ulcers in Horses
Gastrointestinal Obstruction (Blockages) in Horses
Colic in Horses
	Treatment
		Pain Relief
		Fluid Treatment
		Protection against Bacterial Endotoxins
		Intestinal Lubricants and Laxatives
		Surgery
	Specific Causes of Colic and their Treatment
		Distention and Rupture of the Stomach
		Obstruction of the Small or Large Intestine
		Adhesions
		Inflammation of the Small Intestine
		Lipomas
		Twisting or Displacement of the Small or Large Intestine
		Inguinal Hernia
		Enteroliths (Intestinal Stones)
Intestinal Disorders Other than Colic in Horses
	Salmonellosis
	Potomac Horse Fever
	Clostridia-associated Intestinal Inflammation
	Colitis-X
	Parasites
	Intestinal Disease Caused by Eating Sand or Dirt
	Other Causes of Diarrhea in Horses
	Diarrhea in Foals
		Foal Heat Diarrhea
		Bacterial Diarrhea
		Viral Diarrhea in Foals
		Miscellaneous Causes of Diarrhea in Foals
	Gastrointestinal Tumors
	Inflammatory Bowel Disease
	Nonsteroidal Anti-inflammatory Drug Toxicity
	Malabsorption and Maldigestion
		Treatment
		Foals with Lactase Deficiency (Lactose Intolerance)
Gastrointestinal Parasites of Horses
	Ascarids
	Horse Bots
	Large Strongyles
	Small Strongyles
	Tapeworms
	Protozoa
		Cryptosporidiosis
		Giardiasis
Disorders of the Liver in Horses
	Signs of Liver Insufficiency
	Diagnosis
	Treatment and Management
	Acute Hepatitis (Short-term Liver Inflammation)
		Idiopathic Acute Liver Disease (Serum Sickness, Theiler's Disease)
	Tyzzer's Disease
	Cholangiohepatitis
	Poisons Affecting the Liver
	Gallstones (Biliary Calculi, Choleliths)
	Chronic Active Hepatitis
	Hyperlipemia and Hepatic Lipidosis
	Hemochromatosis
	Right Liver Lobe Atrophy
	Liver Lobe Torsion
	Hepatic Amyloidosis
	Primary Hyperammonemia
	Hyperammonemia of Morgan Weanlings
	Portosystemic Shunts
Disorders of the Rectum and Anus in Horses
	Rectal and Anorectal Narrowing (Strictures)
	Rectal Prolapse
	Rectal Tears

Hormonal Disorders of Horses

Introduction to Hormonal Disorders of Horses
	The Endocrine System
	Development of Endocrine System Disease
	Treatment of Endocrine System Disease
Common Hormonal Disorders in Horses
	Cushing's Disease (Hypertrichosis)
	Addison's Disease
	Diabetes Mellitus
	Hypothyroidism
	Goiter
		Iodine Deficiency
		Iodine Toxicity
		Goiter-causing Substances

Eye Disorders of Horses

	Eye Structure and Function in Horses
			Physical Examination of the Eye
	Disorders of the Eyelids in Horses
			Entropion
			Lacerations of the Eyelid
			Inflammation of the Eyelids (Blepharitis)
	Disorders of the Nasal Cavity and Tear Ducts in Horses
			Absence of Nasal Tear Duct Openings
			Inflammation of the Tear Sac (Dacryocystitis)
			Dry Eye (Keratoconjunctivitis Sicca)
	Disorders of the Conjunctiva in Horses
			Conjunctivitis (Pink Eye)
	Disorders of the Cornea in Horses
			Corneal Ulcers
			Corneal Abscesses
			Corneal Lacerations
	Disorders of the Anterior Uvea in Horses
			Equine Recurrent Uveitis (Periodic Ophthalmia, Moon Blindness)
	Glaucoma in Horses
	Disorders of the Lens in Horses
			Cataracts
			Lens Displacement
	Disorders of the Retina, Choroid, and Optic Disk (Ocular Fundus) in Horses
			Inflammation of the Retina and Choroid (Chorioretinitis)
			Retinal Detachments
	Disorders of the Optic Nerve in Horses
			Optic Nerve Hypoplasia
			Optic Nerve Atrophy
			Proliferative Optic Neuropathy
	Prolapse of the Eye in Horses
	Eyeworm Disease (Thelaziasis) in Horses
	Cancers and Tumors of the Eye in Horses
			Squamous Cell Carcinoma
			Equine Sarcoids

Ear Disorders of Horses

	Ear Structure and Function in Horses
			Physical Examination of the Ear
	Deafness in Horses
	Disorders of the Outer Ear in Horses
			Aural Plaques
			Flies
			Frostbite
			Immune-mediated Diseases
			Mites
			Ticks
	Otitis Externa in Horses
	Otitis Media and Interna in Horses

Immune Disorders of Horses Bone, Joint, and Muscle Disorders in Horses

Introduction to Bone, Joint, and Muscle Disorders in Horses
Components of the Musculoskeletal System of Horses
Overview of Musculoskeletal Disorders in Horses
Lameness in Horses
	The Lameness Examination
		Imaging Techniques
		Arthroscopy
		Regional Analgesia
Congenital and Inherited Disorders of Bones, Joints, and Muscles in Horses
	Contracted Flexor Tendons
	Glycogen Storage Disease (Glycogenosis)
	Arthrogryposis (Congenital Joint Rigidity)
	Osteochondritis Dissecans
	Polydactyly
	Angular Limb Deformities
	Defects of the Spine
	Hyperkalemic Periodic Paralysis
	Glycogen Branching Enzyme Deficiency
Developmental Orthopedic Disease in Horses
	Osteochondritis Dissecans
		Treatment and Outlook
	Physitis
	Contracted Flexor Tendons
Disorders Associated with Calcium, Phosphorus, and Vitamin D in Horses
	Osteomalacia (Adult Rickets, Bran Disease)
	Enzootic Calcinosis
Joint Disorders in Horses
	Arthritis
		Traumatic Arthritis
		Osteochondritis Dissecans
		Cysts beneath the Cartilage (Subchondral Cysts)
		Septic Arthritis
		Osteoarthritis
	Bursitis
		Fistulous Withers and Poll Evil
		Capped Elbow and Hock
	Tendinitis
	Tenosynovitis
Disorders of the Foot in Horses
	Bone Cyst in the Pedal Bone
	Bruised Sole and Corns
	Canker
	Contracted Heels
	Fracture of the Navicular Bone
	Fracture of the Pedal Bone
	Keratoma
	Laminitis (Founder)
		Signs and Diagnosis
		Treatment and Outlook
	Navicular Disease
	Pedal Osteitis
	Puncture Wounds of the Foot
	Pyramidal Disease (Buttress Foot)
	Quittor
	Sandcrack (Toe Crack, Quarter Crack, Heel Crack)
	Scratches (Greasy Heel)
	Seedy Toe (Hollow Wall)
	Sheared Heels
	Sidebone
	Thrush
Disorders of the Fetlock and Pastern in Horses
	Fractures of Phalanges and Proximal Sesamoids
	Osselets
	Ringbone
	Sesamoiditis
	Villonodular Synovitis
	Windgalls (Windpuffs)
Disorders of the Carpus and Metacarpus in Horses
	Bucked Shins (Sore Shins, Saucer Fractures)
	Degeneration of the Carpal Bones beneath the Cartilage
	Desmitis or Sprain of the Inferior Check Ligament
	Fracture of the Carpal Bones
		Chip Fragments
		Carpal Slab Fractures
		Accessory Carpal Fractures
	Fractures of the Splint Bones
	Fracture of the Cannon Bone
	Hygroma
	Osteoarthritis (Degenerative Joint Disease)
	Osteochondroma of the Distal Radius
	Rupture of the Common Digital Extensor Tendon
	Splints
	Cysts Beneath the Cartilage and Septic Arthritis
	Inflammation of the Suspensory Ligament (Suspensory Desmitis)
		Inflammation of the Top Third of the Suspensory Ligament
		Inflammation of the Body of the Suspensory Ligament
		Inflammation of the Branches of the Suspensory Ligament
	Hernias, Lumps, and Splints in the Synovial Joint Membrane
	Torn Medial Palmar Intercarpal Ligament
	Inflammation of the Tendon Sheaths Associated with the Carpus
	Inflammation of the Synovial Membrane and Fibrous Joint Capsule
Disorders of the Shoulder and Elbow in Horses
	Arthritis of the Shoulder Joint
	Bicipital Bursitis
	Elbow Fractures
	Shoulder Fractures
	Sweeney (Shoulder Atrophy)
Disorders of the Tarsus in Horses
	Bog Spavin (Inflammation of the Hock Joint)
	Bone Spavin
	Curb
	Displacement of the Superficial Flexor Tendon from the Point of the Hock
	Fracture of the Tarsus
	Hindlimb Tendon and Muscle Ruptures
	Stringhalt (Springhalt)
	Thoroughpin
Disorders of the Stifle in Horses
	Fracture of the Stifle
	Gonitis
	Dislocation of the Kneecap (Patella)
	Bone Cyst beneath Cartilage
Disorders of the Hip in Horses
	Coxitis
	Dislocation of the Hip
	Pelvic Fracture
	Trochanteric Bursitis (“Whirlbone” Lameness)
Disorders of the Back in Horses
	Fractures
	Muscle and Ligament Strain
	Degenerative Diseases of the Spine
	Kissing Spine Syndrome
	Sacroiliac Injury (Dislocation, Strain, Arthrosis, Hunter's Bumps)
Muscle Disorders in Horses
	Nutritional Myopathies of Horses
		Selenium or Vitamin E Deficiency
		Yellow Fat Disease (Steatitis)
	Exertional Myopathies in Horses
		Sporadic Exertional Rhabdomyolysis (Tying Up)
		Chronic Exertional Rhabdomyolysis
		Hyperkalemic Periodic Paralysis
	Toxic Myopathies
		Ionophore Toxicity
		Plant Intoxication
	Circulatory Disturbances
	Fibrotic and Ossifying Myopathy in Quarter Horses
	Immune-mediated Myositis
Sarcocystosis in Horses

Brain, Spinal Cord, and Nerve Disorders of Horses

The Nervous System of Horses
Parts of the Nervous System in Horses
	Neurons
		Types of Neurons
Nervous System Disorders and Effects of Injuries in Horses
	Mechanisms of Disease
The Neurologic Evaluation in Horses
	The Neurologic Examination
		Evaluation of the Cranial Nerves
		Evaluation of Gait (Walking)
		Evaluation of the Neck and Front Legs
		Evaluation of the Torso, Hind Legs, Anus, and Tail
	Laboratory Tests and Imaging
Principles of Therapy of the Nervous System in Horses
Congenital and Inherited Disorders of the Nervous System in Horses
	Forebrain Disorders
	Cerebellar Disorders
	Spinal Cord Disorders
	Peripheral Nerve and Muscle Disorders
Disorders of the Peripheral Nerves in Horses
	Degenerative Diseases
	Inflammatory Disorders
	Toxic Disorders
	Injury and Trauma
Disorders of the Spinal Column and Cord in Horses
	Degenerative Diseases
	Inflammatory and Infectious Diseases
		Viral Diseases
		Fungal Diseases
		Protozoal Diseases
		Parasitic Diseases
	Poisoning and Toxic Disorders
Equine Dysautonomia (Grass Sickness)
Equine Viral Encephalomyelitis (Encephalitis)
	Risk to People
Equine Protozoal Myeloencephalitis
Facial Paralysis in Horses
Central Nervous System Disorders Caused by Parasites in Horses
	Tapeworms
	Roundworms
	Disease Caused by Insects
Neonatal Encephalopathy in Foals (Neonatal Maladjustment Syndrome)
Leg Paralysis in Horses
Meningitis and Encephalitis in Horses
Rabies in Horses
	Risk of Passing Rabies to People
West Nile Encephalomyelitis in Horses
	Transmission to People

Reproductive Disorders of Horses

Introduction to Reproductive Disorders of Horses
The Gonads and Genital Tract of Horses
	The Ovaries
	The Testes
	The Female Genital Tract
	The Male Genital Tract
Management of Reproduction in Horses
	Reproductive Cycle and Breeding Management
	Detecting Estrus
	Health Programs During Pregnancy
		Parasite Control
		Vaccinations
	Foaling
		Preparation
		Stages of Delivery
		The Early Postdelivery Period
Infertility in Horses
Congenital and Inherited Disorders of the Reproductive System in Horses
Abortion in Horses
	Noninfectious Causes
	Infectious Causes
Brucellosis in Horses
Contagious Equine Metritis
Equine Coital Exanthema (Genital Horsepox, Equine Venereal Balanitis)
Mastitis in Horses
Metritis in Horses
Pyometra in Horses
Retained Placenta in Horses
Uterine Prolapse in Horses
Vulvitis and Vaginitis in Horses

Lung and Airway Disorders of Horses

Introduction to Lung and Airway Disorders of Horses
	Causes of Lung and Airway Disorders
	Diagnosing Lung and Airway Disorders
	Control of Respiratory Conditions
	General Treatment of Lung and Airway Disorders
Accumulation of Fluid or Air in the Chest Cavity of Horses
Aspiration Pneumonia in Horses
Choanal Atresia in Horses
Diaphragmatic Hernia in Horses
Disorders of the Larynx in Horses
	Arytenoid Chondritis (Laryngeal Chondropathy)
	Laryngeal Hemiplegia (Roaring)
	Fourth Branchial Arch Defect
Disorders of the Nasal Septum in Horses
Disorders of the Paranasal Sinuses in Horses
	Sinusitis
	Ethmoid Hematoma
	Sinus Cysts
Dorsal Displacement of the Soft Palate in Horses
Epiglottic Entrapment in Horses
Equine Herpesvirus Infection (Equine Viral Rhinopneumonitis)
Equine Influenza
Equine Morbillivirus Pneumonia (Hendra Virus Infection)
Equine Viral Arteritis
Exercise-induced Pulmonary Hemorrhage (Bleeder) in Horses
Foal Pneumonia
	Rhodococcus equi Pneumonia
		Treatment and Prevention
	Acute Bronchointerstitial Pneumonia in Foals
Guttural Pouch Empyema in Horses
Guttural Pouch Mycosis in Horses
Guttural Pouch Tympany in Horses
Inflammatory Airway Disease in Horses
Lungworm Infection in Horses
Nasal Polyps in Horses
Pharyngeal Lymphoid Hyperplasia (Pharyngitis) in Horses
Pleuropneumonia in Horses
Recurrent Airway Obstruction (Heaves) in Horses
	Summer Pasture-associated Obstructive Lung Disease
Strangles (Distemper) in Horses
	Treatment and Control
Subepiglottic Cyst in Horses

Skin Disorders of Horses

Structure of the Skin in Horses
	Epidermis
	Basement Membrane Zone
	Dermis
	Skin Appendages
	Subcutis
Dermatitis and Dermatologic Problems of Horses
Diagnosis of Skin Disorders in Horses
Treatment of Skin Disorders in Horses
Congenital and Inherited Skin Disorders in Horses
	Congenital Skin Disorders
	Pigmentary Abnormalities
	Defects of Structural Integrity
Allergies in Horses
	Airborne Allergies (Atopy)
	Food Allergies
Dermatophilosis in Horses
Eosinophilic Granuloma Complex in Horses
Flies and Mosquitoes of Horses
	Biting Midges (Gnats, No-see-ums)
	Black Flies
	Buffalo Flies
	Eye Gnats
	Face Flies
	Filth-breeding Flies
		Fly Strike (Myiasis)
	Horn Flies
	Horse Flies
	Mosquitoes
	Stable Flies
	Tsetse Flies
Hair Loss (Alopecia) in Horses
Hives (Urticaria) in Horses
Itching (Pruritus) in Horses
Lice of Horses
Mange (Acariasis, Mange Mites) in Horses
	Sarcoptic Mange (Scabies, Body Mange)
	Psoroptic Mange (Mane Mange)
	Chorioptic Mange (Leg Mange)
	Demodectic Mange
	Harvest Mites (Chiggers, Trombiculids)
	Straw Itch Mites (Forage Mites)
Parasitic Worms of the Skin in Horses
	Cutaneous Habronemiasis (Summer Sores)
	Onchocerciasis
	Parafilaria multipapillosa Infestation (Summer Bleeding)
	Pelodera Dermatitis
Photosensitization in Horses
Ringworm (Dermatophytosis) in Horses
Saddle Sores (Collar Galls) in Horses
Ticks of Horses
	Treatment and Control
Tumors of the Skin in Horses
	Basal Cell Tumors and Carcinomas
	Collagenous Nevi
	Equine Sarcoids
	Fibromatosis
	Keratinized Skin Cysts
	Lipomas and Liposarcomas
	Lymphoid Skin Tumors
	Mast Cell Tumors
	Melanomas
	Neurof ibromas and Neurof ibrosarcomas
	Sebaceous Gland Tumors
	Soft Tissue Giant Cell Tumors (Malignant Fibrous Histiocytomas)
	Squamous Cell Carcinomas
	Sweat Gland Tumors
	Tumors Originating Outside the Skin (Metastatic Tumors)
	Vascular Tumors
	Warts (Papillomas)

Kidney and Urinary Tract Disorders of Horses Metabolic Disorders of Horses

	Introduction to Metabolic Disorders of Horses
			Metabolic Storage Disorders
			Production-related Metabolic Disorders
	Disorders of Calcium Metabolism in Horses
	Disorders of Magnesium Metabolism in Horses
	Fatigue and Exercise in Horses
			Fatigue during High-intensity Exercise
			Fatigue during Prolonged Exercise
			Prevention of Fatigue
			Recovery
	Fever of Unknown Origin in Horses
	Malignant Hyperthermia in Horses

Disorders Affecting Multiple Body Systems of Horses

	Introduction to Disorders Affecting Multiple Body Systems in Horses
	Congenital and Inherited Disorders Affecting Multiple Body Systems in Horses
			Genetic Factors
			Environmental Factors
	Actinobacillosis in Horses
	Actinomycosis in Horses
	African Horse Sickness
	Amyloidosis in Horses
	Anaplasmosis in Horses (Equine Granulocytic Ehrlichiosis)
	Anthrax in Horses
	Besnoitiosis in Horses
	Botulism in Horses
	Equine Infectious Anemia
	Equine Morbillivirus Pneumonia (or Hendra Virus Infection)
	Equine Viral Arteritis
			Treatment and Control
	Fungal Infections (Mycoses) in Horses
			Aspergillosis (Guttural Pouch Mycosis)
			Candidiasis
			Coccidioidomycosis (Valley Fever)
			Cryptococcosis
			Epizootic Lymphangitis
			Pythiosis
			Phaeohyphomycosis
			Rhinosporidiosis
			Sporotrichosis
			Zygomycosis (Basidiobolomycosis, Conidiobolomycosis)
	Glanders (Farcy) in Horses
	Infectious Necrotic Hepatitis (Black Disease) in Horses
	Intestinal Clostridiosis (Clostridia-associated Enterocolitis) in Horses
			Enterotoxemia Caused by Clostridium in Foals
	Leptospirosis in Horses
	Lyme Disease (Lyme Borreliosis) in Horses
	Malignant Edema in Horses
	Melioidosis in Horses
	Nocardiosis in Horses
	Peritonitis in Horses
	Septicemia in Foals
			Treatment and Outlook
	Tetanus in Horses
	Trichinellosis (Trichinosis) in Horses
	Tuberculosis in Horses
	Tularemia in Horses
	Vesicular Stomatitis in Horses

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