Conditions

Photosensitization, or light-induced dermatitis (photodermatitis), is a noncontagious condition in horses where the skin becomes extremely sensitive to sunlight. This condition often mimics a sunburn, but it is much more serious and painful. Photosensitization is most commonly caused by ingesting...

It’s not uncommon for horses to experience eye problems. Several conditions and diseases can affect vision and eye health in horses, including uveitis, cataracts, and conjunctivitis. Horses experiencing eye issues may have symptoms such as swelling, tearing, drainage, discoloration, cloudiness,...

Myosin Heavy Chain Myopathy (MYHM) is a muscle disease that can affect Quarter Horses and related breeds with the associated mutation in the MYH1 gene. MYH1, also called myosin heavy chain 1, is a gene that encodes a type of...

Coughing is a common clinical sign in horses that can be entirely benign or the first clue of a medical condition. Your horse’s cough is a normal reflex that keeps his airway healthy and clean. But some conditions associated with...

Lasix (furosemide) is a medication routinely used to prevent lung bleeding in horses with exercise-induced pulmonary hemorrhage (EIPH). This bleeding disorder is prevalent in racehorses following bouts of high-intensity exercise. Veterinarians often recommend treating with Lasix on race days to...

Retained fetal membranes (RFM), also referred to as retained placenta, is a condition that affects a small percentage of broodmares. RFM can lead to serious medical complications in affected mares and requires prompt treatment. Potential complications of RFM include laminitis,...

Shipping fever is a lower respiratory tract infection seen in horses transported over long distances or experiencing unusual or stressful events. Known causes of shipping fever include prolonged periods of head elevation, strenuous exercise, anesthesia or complications from a viral...

Sand colic is a term for abdominal pain in horses caused by the ingestion of sand. Depending on the geographic region, five to thirty percent of all colic cases are caused by sand or sediment accumulation in the gut. Sand...

Of the many skin conditions horses can develop, sarcoids are the most common. The term "sarcoid" was first used in 1936 in South Africa as a way to distinguish this skin lesion from other tumors. Sarcoids are benign (nonmetastatic) skin...

Myofibrillar myopathy (MFM) is a newly identified muscle disorder that causes exercise intolerance in horses. MFM is a genetic condition that results from the abnormal build-up of desmin in muscle tissue. Desmin is a protein that is important for muscle...

Slobbers, otherwise known as slaframine poisoning or salivary syndrome, is a condition that causes excessive salivation or drooling in horses. It is relatively rare and usually occurs in outbreaks, with multiple horses affected at once. Slaframine intoxication is caused by...

Glycogen branching enzyme deficiency (GBED) is a fatal disorder caused by a gene mutation found in the Quarter Horse and Paint Horse bloodlines. GBED causes abortion in late-term pregnancies, stillbirth or severe muscle weakness and eventually death in newborn foals....

Black walnut tree poisoning occurs when horses come into contact with toxic compounds in the black walnut (Juglans nigra) tree. The roots, bark, wood, nuts, pollen and leaves of the tree contain a chemical that is poisonous to horses upon...

Horses are prone to a number of different skin conditions and diseases. Some are minor and resolve on their own, while others can be much more serious. Skin conditions may affect localized areas on the horse, such as the legs...

Equine grass sickness (EGS), or equine dysautonomia, is a rare and fatal disease in horses. It almost exclusively affects grazing horses kept on pasture. EGS is characterized by the development of severe lesions on the neurons of the peripheral and...

Pain is something that all horses deal with at some point in their lives. Horses can experience pain for many different reasons, including injury, illness, or a result of surgery. For example, castration is the most common surgical procedure performed...

Stringhalt, or equine reflex hypertonia, is a neuromuscular condition that causes abnormal hindlimb movement in the horse. Horses with stringhalt have excessive and prolonged flexion of the pelvic limbs while in forward movement, showing signs of the condition at most...

A large, round belly doesn't always mean your horse is overweight. Some horses have a hay belly that makes them appear pregnant, yet they may struggle to maintain enough body condition to cover their ribs. While multiple factors contribute to...

Bone spavin, also known as Degenerative Joint Disease (DJD) of the hock (tarsus), is an extremely common cause of equine lameness. It is caused by repeated concussion and rotational forces on the hock joint, as well as excessive forces on...

Equine herpesvirus (EHV), or rhinopneumonitis, is a contagious infection that is endemic to horses worldwide. EHV may cause mild to severe symptoms that usually involve the upper respiratory tract. In rare cases, it may cause neurological symptoms, abortion or death....

Botflies (Gasterophilus spp.) are parasitic flies that affect the horse's digestive tract and can cause negative health consequences. Botflies lay eggs on the horse's coat in the summer. Some of these eggs, known as horse bots, are ingested as the...

Equine COPD - or chronic obstructive pulmonary disease - is a now-obsolete term for a common condition in horses that causes coughing and poor performance. This condition is now referred to as equine asthma and is one of the most...

Lymphangitis, also known as big leg disease or stovepipe leg, is a condition in horses involving inflammation of the lymph vessels, most often in the lower limb. Lymphangitis presents as extreme swelling with rapid onset, resulting in pain in the...

Equine asthma (EA) is a relatively new collective term for chronic respiratory signs in horses that range in severity from mild to severe. These conditions were previously known as inflammatory airway disease (IAD) or recurrent airway obstruction (RAO), respectively. Equine...

Chronic kidney disease (or chronic renal failure) in horses is a rare but serious disorder that interferes with normal kidney function. Your horse's kidneys perform many important processes in the body including managing blood pressure, excreting waste products, and regulating...

Obesity is a health concern in horses worldwide, with a prevalence estimated between 31 – 45% in some equine populations. Among ponies and easy keeper breeds, the prevalence is even higher with one study reporting that 72% of adult ponies...

Stagnation edema, also known as stocking up, is a common cause of leg swelling in stabled horses. It occurs due to impaired circulation from periods of reduced activity. This short-lasting form of edema typically affects both hind limbs and causes...

Horses can experience a number of different dental issues over their lifetime, impacting their ability to chew and digest their feed. Unaddressed dental issues can affect your horse's health, condition, behaviour and performance. This is why it’s important to have...

Equine influenza virus, or EIV, is an extremely contagious respiratory disease or flu affecting horses, mules, and donkeys. EIV is characterized by fever, apathy, and lack of appetite, and causes respiratory symptoms such as coughing and nasal discharge. However, some...

Nutritional myodegeneration (NMD), more commonly known as white muscle disease, is a disorder that affects various animals, including horses. In equids, the condition primarily occurs in newborn foals, although adult horses can also develop it. The condition results in degeneration...