abaxial (fracture): see sesamoids.

abscess: an infection around which the body has constructed a wall of fibrous tissue, to isolate it. Treatment with antibiotics is more likey to be effective if drainage of the abscess can be established, eliminating accumulated pus and debris.

action: a horse’s manner of moving.

acupressure: utilizing stimulation on acupuncture points to treat an animal.

acupuncture: a centuries-old means of treating an animal or human through  use of needles, electrical current, or moxibustion (heat and herbs) to stimulate or realign the body’s electrical fields.

acute: referring to a disease: An acute disease is a disease of short, sharp course.

age: many breeds, including Thoroughbreds and Quarter Horses, celebrate a common birthday on Jan 1.

agent: a person empowered to transact business for a stable owner or jockey, or empowered to sell or buy horses for an owner or breeder.

AHS: African Horse Sickness.

all out: when a horse extends itself to the utmost.

alternative therapy: a group of therapies (acupuncture, chiropractic,  physical therapy, herbology, naturopathy) that help maintain the horse’s health and performance but without using medication.

angular limb deformities: a limb that is crooked because of developmental problems in the angles of the joints. A problem of young horses, often present immediately after birth.

anhydrosis: inability to sweat in response to work or an increase in body temperature. Also known as a “non-sweater.” Athletic horses are affected most frequently, though the condition also appears in pastured horses that are not being ridden. Most commonly occurs when both temperature and humidity are high. Horses raised in temperate regions and then transported to hot climates are most prone to develop the condition, but even acclimated horses can be at risk. Clinical signs include inability to sweat, increased respiratory rate, elevated body temperature and decreased exercise tolerance. The condition can be reversed if the horse is moved to a more temperate climate.

anterior enteritis: acute inflammation of the small intestine producing signs of abdominal distress such as colic and diarrhea.

anterior: toward the front of the horse’s body.

aortic rupture: bursting of the aorta (artery coming from the left of the heart that distributes blood to nearly all of the body).

apical (fracture): see sesamoids.

arthritis: inflammation of a joint. An increase in the amount of synovial fluid in the joint is a result of the inflammation. Accumulation of synovial fluid in the fetlock joint is called a “wind puff” or “wind gall.” See also “green osselet.”

arthroscope: a tiny tube of lenses used for viewing areas inside a joint. Usually attached to a small video camera.

arthroscopic surgery: surgery performed through the use of an arthroscope which eliminates the need to open the joint with a large incision in order to view the damaged area.

articular cartilage: cartilage that covers the ends of bones where they meet in a joint.

artificial breeding: includes artificial insemination or embryo transfer (transplant).

arytenoid cartilages: triangular cartilages in the upper part of the entrance to the larynx. Movements of the arytenoids cartilages control the diameter of the laryngeal opening.

ataxia: loss or failure of muscular coordination.

atrophy: to waste away, usually used in describing muscles.

avermectin: a class of dewormer products. The equine product ivermectin is a member of this class.



back at the knee: a leg that looks like it has a backward arc with its center at the knee when viewed from the side.

bad doer: a horse with a poor appetite, a condition that may be due to nervous-ness or other causes.

bandage: bandages used on horses’ legs are 3 to 6 inches wide and are made of a variety of materials. In a competition, they are used for support or protection against injury. A horse may also wear “standing bandages,” thick cotton wraps used during shipping and while in the stall to prevent swelling and/or injury.

bar shoe: a horseshoe closed at the back to help support the frog and heel of the hoof. It is often worn by horses with quarter cracks or bruised feet.

barren: used to describe a filly or mare that was bred and did not conceive during the last breeding season.

basilar (fracture): see sesamoids.

bay: a horse color that varies from a yellow-tan to a bright auburn. The mane, tail and lower portion of the legs are always black, except where white markings are present.

benign: referring to a cancerous growth: Not invasive or destructive, and not tending to spread to other areas of the body.

bit: mouthpiece made of variety of materials, including stainless steel, rubber or aluminum, jointed or unjointed, and attached to the bridle. It  is one of the means by which a rider exerts guidance and control. Three common types of bits are the snaffle, Pelham and curb.

black walnut shavings toxicosis: an as-yet unexplained poisoning from skin contact with wood shavings made from the black walnut tree, most often the consequence of unknowingly using them to bed a stall. (Anecdotal evidence suggests that other walnut varieties may also be toxic.) Vasculitis and laminitis are virtually guaranteed and usually severe. Treament involves removing the walnut shavings and treating the resultant vasculitis and/or laminitis.

black: a horse color which is black, including the muzzle, flanks, mane, tail and legs unless white markings are present.

blaze: a generic term describing a large, white vertical marking of medium width running the length of the horse’s face.

bleeder (see exercise-induced pulmonary hemorrhage): a horse that bleeds from the lungs when small capillaries rupture into the air sacs. The medical term is Exercise-Induced Pulmonary Hemorrhage (EIPH). Blood may be seen coming out of the horse’s nostrils. This is termed epistaxis. Diagnosis of EIPH is typically made during a post-exercise veterinary examination using a fiberoptic endoscope. The procedure is referred to as an endoscopic examination. Less than one bleeder in 20 shows signs of epistaxis (blood at the nostrils). Hot, humid weather and cold weather are known to exacerbate the problem. The most common preventive treatment currently available is the use of the diuretic furosemide (Salix™).

blister beetle poisoning: poisoning due to ingestion of a beetle, typically 1/2 inch long, solid black or black with yellow stripes. It inhabits some alfalfa fields and other forages, and contains a powerful stomach irritant called canthardin. Most poisonings occur when the beetle is killed and baled into your horse’s hay, then ingested. The toxin can cause severe colic due to burning of the stomach lining. Ingestion of only a few beetles can be fatal to a full-grown horse and treament is symptomatic and supportive. Prognosis is guarded: As many as half of all patients die despite vigorous therapy.

blister: counter-irritant causing acute inflammation. Used to increase blood supply and blood flow, and to promote healing in the leg.

bloodstock agent: a person who advises and/or represents a buyer or seller of horses at a public auction or a private sale. A bloodstock agent usually works on commission, often five percent of the purchase price, and can also prepare a horse for sale.

blue roan: in Quarter horses, a more or less uniform mixture of white with black hairs over a large portion of the body, but usually darker on head and lower legs; can have a few red hairs in the mixture.

bog spavin: a soft swelling caused by excess synovial fluid of the largest joint of the hock called the “tibiotarsal joint.”

bone grafts: utilizing bone taken from one part of the body to promote formation of bone in another region.

bone spavin: bone spavin is arthritis of the lower portion of the hock. Most commonly, bone spavin appears as a hard swellling on the inner (joint) surface, where the hock meets the cannon bone. It also can occur in the lower aspect of your horse’s hock joint without visible enlargement. Lameness is common but can be difficult to detect because both hind limbs are often affected. Pain is often associated with flexing and advancing the affected the affected limb(s), causing your horse to carry the leg(s) abnormally and/or drag his toe, as revelaed by unusual wear patterns there.

boots: any of a number of devices strapped or hung from a horse’s legs and coronets designed to offer protection from injury.

bottom line: a horse’s breeding on the female side. The lower half of an extended pedigree diagram.

bottom: 1) stamina in a horse. 2) subsurface of a racing strip.

botulism, forage poisoning: disease caused by the nerve-poisoning toxin of the bacteria Clostridium botulinum which live in certain soils, wounds and in decaying organic matter. The first signs in adult horses can include loss of tongue, tail and eyelid tone, resulting in subtle changes in the face and tail carriage that often go unnoticed. As the disease progresses, swallowing can become difficult, resulting in quidding, drooling, tongue lolling and/or bad breath, followed by weakness, gait instability, collapse and death by respiratory paralysis. Intensive-care treament, including administration of botulism antitoxin, is successful in approximately 70 percent of cases.

bowed tendon: tendonitis. The most common injury to the tendons is a strain or “bowed tendon” so named because of the appearance of a bow shape due to swelling. The most common site of injury is in the superficial digital flexor tendon between the knee and the ankle behind the cannon bone. Despite aggressive treatment with anti-flammatory drugs, physical therapy and rest, horses frequently reinjure the tendon when they go back into competition. Two surgeries are felt to aid horses to come back to competition: tendon splitting at the lesion site to release accumulated fluid and blood, and superior check ligament desmotomy (dissection of the ligament). The latter surgery, which involves severing one of the upper attachments of the tendon, is designed to reduce forces on the tendon when the horse returns to training and competing. Diagnostic ultrasound is the most common method of diagnosing this condition and monitoring the healing process.

brace or bracer: rubdown liniment used on a horse after a workout.

breakdown: when a horse expereices a potentially career-ending injury, usually to the leg involving a fracture. Some can be repaired with surgery and physical therapy.

breastplate: piece of tack that fits across the horse’s chest and is attached to the saddle. Its purpose is to prevent the saddle from slipping backward.

breather: easing off a horse for a short distance in a speed effort to conserve or renew its strength.

bred: 1) a horse is considered to have been bred in the state or country of its birth: Secretariat was a Virginia-bred. 2) the past tense of “breed.”

breed: 1) a sort or type of horse. 2) to reproduce

breeder: owner of the dam at time of foaling unless the dam was under a lease or foal-sharing arrangement at the time of foaling. In that case, the person(s) specified by the terms of the agreement is (are) the breeder(s) of the foal.

breeding fund: a state fund set up to provide bonuses for state-breds.

breeze (breezing): working a horse at a moderate speed, less effort than handily.

bridle: a piece of equipment, usually made of leather or nylon, which fits on a horse’s head and to which other equipment, such as a bit and the reins, are attached.

broken wind: see chronic obstructive pulmonary disease.

brush: injury that occurs when one hoof strikes the inside of the opposite limb.

bucked shins: inflammation of the covering of the bone (periosteum) of the front surface of the cannon bone. Usually seen in two-to three-year-old Thoroughbreds. See periostitis.

bulbs of the heel: the two areas on either side of the back of the foot, similar to the heel of the hand.

bursa: a sac containing synovial fluid (a natural lubricant). Acts as a pad or cushion to facilitate motion between soft tissue and bone. Most commonly found where tendons pass over bones.

bursitis: inflammation in a bursa that results in swelling due to accumulation of synovial fluid. Capped elbow is inflammation of the bursa over the point of elbow (olecranon process of the ulna). Capped hock is inflammation of the bursa over the point of the hock (tuber calcis).

bute: short for phenylbutazone, a non-steroidal anti-flammatory medication.

buy-back: a horse out through a public auction that did not reach a minimum (reserve) price set by the consignor and so was retained. The consignor must pay a fee to the auction company based on a percentage of the reserve, to cover the auction company’s marketing, advertising and other costs.

BVMS: Bachelor of Veterinary Medicine and Surgery. Equivalent to DVM. Awarded in United Kingdom.

BVSc: Bachelor of Veterinary Science. Equivalent to DVM. Common veterinary degree description outside the United States.



C.N.S.: central nervous system.

calk or caulk: a projection on the heels of a horseshoe, similar to a cleat, to prevent slipping, especially on wet turf.

canker: an infection of the frog that can spread to the adjacent sole and hoof wall. The affected frog grows thick folds and ridges, and a foul-smelling, cottage-cheese like exudate oozes from the crevices. Affected feet are usually lame. Canker is most often caused by long term hoof neglect and wet, filthy footing. Because infection is often quite deep, successful treament might require surgical debridement and systemic antibiotics.

cannon bone: the third metacarpal (front leg) or metatarsal (rear leg), also referred to as the shin bone. The largest bone between the knee and fetlock (ankle) joints.

canthardin poisoning: see “blister beetle” poisoning.

capillary refill time: the amount of time it takes for blood to return to capillaries after it has been forced out, normally two seconds. It is usually assessed by pressing the thumb against the horse’s gums; when the pressure is removed the gum looks white, but the normal pink color returns within two seconds as blood flows into the capillaries. A delayed capillary refill time is an indication of dehydration.

capped elbow: inflammation of the bursa over the point of elbow (olecranon process of the ulna). Also known as “shoe boil.” See bursitis.

capped hock: inflammation of the bursa over the point of the hock (tuber calcis). See bursitis.

carpus: a collection of three joints halfway up the horse’s front leg, more commonly referred to as the knee. However, the carpus is actually equivalent to the human wrist.

cast: 1) a horse positioned on its side or back with its legs wedged against a wall such that it can not get up. 2) A fiberglass cast that is applied to a horse’s leg to protect it in the event of a fracture or injury.

cataract: loss of transparency of an eye lens. Once a lens becomes clouded, there is no treament to restore it. If the cataract is large enough to block vision, the lens may be removed surgically, which permits the horse to see, but not to focus.

cathartic: a laxative given to quickly purge your horse’s bowels of their contents. Examples include epsom salt solution, mineral oil or psyllium.

caudal: toward the tail of the horse.

CBC: Complete Blood Count.

cellulitis: inflammation of cells and connective tissue, usually associated with deep skin conditions such as scratches or greasy heel.

chestnut: 1) a horse color which may vary from a red-yellow to golden-yellow. The mane, tail and legs are usually variations of coat color, except where white markings are present. 2) horny growth on the inner side of the legs. On the forelegs, they are just above the knees. On the hind legs, they are just below the hocks. No two horses have been found to have the same chestnuts and so they may be used for identification. Also called “night eyes.”

chiropractic: use of bone alignment by veterinarians or under a veterinarian’s direction to treat malalignment problems.

choke: an object or wad of feed lodged in your horse’s esophagus. Muscles around the obstruction clench in response, prolonging the choke and increasing the odds of damage to esophageal lining, which can lead to narrowing of the esophagus due to scar tissue. (A narowed esophagus is prone to repeated chokes.) During a choke, food, water and saliva are regurgitated through one or both nostrils and your horse may cough and/or retch. Encouraging the choked horse to keep his head lowered can help prevent regurgitated material from spilling into the windpipe (trachea), which can cause aspiration pneumonia. Treatment can include: gentle irrigation and suction of impacted feed with warm water or saline through a stomach tube, removal of any lodged foreign matter with an operating endoscope or by surgery (a last resort) if it can’t be removed endoscopically, and/or diagnosis and treatment of any underlying problem that caused the choke. Anti-inflammatory medications usually are given to soothe tissues inflamed by the choke and treatment. Treatment for aspiration pneumonia is administered, if necessary.

choking down: see dorsal displacement of the soft palate.

chronic obstructive pulmonary disease: commonly known as “COPD,” a hyperallergenic response of the respiratory system that involves damage to the lung tissue, similar in may ways to human asthma. Affected horses may cough, develop a nasal discharge and have a reduced exercise tolerance. Respiratory rate is increased and lung elasticity is diminished.

chronic osselet: permanent build-up of synovial fluid in a joint, characterized by inflammation and thickening of the joint capsule over the damaged area. Usually attended by changes in the bone and cartilage. See arthritis.

chronic: a disease or condition of long duration.

CL: corpus luteum. A progesterone secreting gland in the ovary formed from the wall of an ovarian follicle.

clerk of scales: an official whose chief duty is to weigh the riders and tack after a race or competition to ensure proper weight is (was) carried.

climbing: when a horse lifts its front legs abnormally high as it gallops, causing it to run inefficiently.

closed knees: a condition where the cartilaginous growth plate above the knee (distal radial physis) has turned to bone. Indicates completion of long bone growth and is one sign of maturity.

coffin bone fracture: a fracture that usually is associated with a misstep or fall;  commonly seen on the inside (and more consistently stressed) leg of racehorses. Symptoms usually include sudden onset lameness, heat that can be felt on the hoof wall and increased digital pulse. Treatment depends on the fracture’s location and on how unstable it is. Some cases heal well with 12 months’ rest and application of a bar shoe to limit hoof flexion. Others require surgery and stabilization of the fracture with bone screws.

coffin bone: the third phalanx (P3). The major bone within the confines of the hoof. Also called the “pedal [PEE-dal] bone.”

coggins test: a blood test to detect infection with the virus that causes Equine Infectious Anemia (EIA). The disease is spread by biting insects that feed on infected horses, then carry the virus to other horses. Many events such as shows and rodeos require recent (6 to 12 months) negative Coggins tests on all participants, and most states require negative Coggins test in horses crossing their borders. Horses testing positive become subject to state law that requires quarantine away from biting insects and other horses, or euthanasia. There is no known cure and no vaccine.

colic: refers to abdominal pain, usually due to intestinal problems and/or gas build-up.

colitis: inflammation of the colon, usually due to infection. Diarrhea, colic pain and rapidly progressing dehydration are usually the result. Treatment focuses on relieving symptoms and preventing dehydration and shock while identifying and treating the underlying cause, if possible.

colors (horse): include bay, black, chestnut, dark bay or brown, dun, gray, palomino, roan, sorrel, white.

colt: an ungelded (entire) male horse four years old or younger.

comminuted (fracture): a fracture with more than two fragments.

compound (fracture): a fracture where damaged bone breaks through the skin. Also known as an “open” fracture.

condylar (fracture): a fracture in the lower knobby end (condyle) of a long bone, such as the cannon bone or humerous.

conformation: the physical make-up and bodily proportions of a horse; how it is put together.

congential: present at birth.

conjunctivitis: inflammation and/or infection of the tissues around the eye. Symptoms can include reddening, itching, watering and swelling. Causes can include irritants such as dust or flies; trauma and infection. Treatment usually includes gently cleaning, addressing the underlying cause and medicating with ointments containing appropriate antibiotics and/or anti-inflammatory medication.

cooling out: reducing a horse’s temperature after exercise, usually by walking. All horses that are exercised are cooled out. Horses that work hard in hot, humid weather have difficulty cooling out. Under these circumstances cold water may be applied to their bodies and the excess water scraped off to assist cooling.

COPD, chronic obstructive pulmonary disease, heaves: see Heaves, chronic obstructive pulmonary disease, COPD.

corn: a bruise on the sole of the foot, toward the heel as a result of pressure from the shoe.

cornea: the transparent, domed portion

corneal abscess: an infection between the onion-like layers of the cornea, most associated with a penetrating wound. The condition is painful and, if unresolved, can result in blindness. Treament is chanllenging since the location of the infection between corneal layers makes it difficult for topical or systemic medications to penetrate to the site. Treatment usually is similar to that of a corneal ulcer; in nonresponsive cases, surgery may be needed to remove corneal layers and expose the abscess. (If the infection is resolved, the cornea will heal.)

corneal ulcer: a defect in the cornea, most often associated with injury and subsequent infection. The condition is painful and, if unresolved, can result in blindness. Treatment usually includes antibiotics and other medications to combat infection, inflammation and pain and facilitate repair of the damaged cornea. In most cases, topical treatment is used.

coronary band: where the hoof meets the skin of the leg.

corticosteriods: hormones that are either naturally produced by the adrenal gland or manmade. Perform an anti-inflammatory function and regulate the chemical stability (homeostasis of the body).

cough: to expel air from the lungs in a spasmodic manner. Can be a result of inflammation or irritation to the upper airways (pharynx, larynx or trachea) or may involve the lower airways of the lungs (deep cough).

cover: 1) a single breeding of a stallion to a mare. 2) in race-driving, the horse racing immediatley in front of another is said to be the “cover” of the trailering horse. The horse behind the cover has a horse cutting the wind, but, obviously, trails by at least a length.

cow hocks: abnormal conformation in which the points of the hocks turn in when viewed from behind.

cracked hoof wall: a vertical split of the hoof wall. Cracks may extend upward from the bearing surface of the wall or downward from the coronary band, as the result of an injury to the band. Varying in degrees of severity, cracks can result from injuries or concussion. Hooves that are dry and/or thin (shelly) or improperly shod are susceptible to cracking upon concussion. Corrective trimming and shoeing may remedy mild cracks, but in severe cases when the crack extends inward to the sensitive laminae, more extensive treatment is required, such as using screws and wires to stabilize the sides of the crack.

cranial: toward the head of the horse.

creep feeder: a feeding device designed to allow a foal to eat but keep its dam out. Otherwise, the mare will eat the foal’s food.

cribber (wind sucker): horse who clings to objects with his teeth and sucks air into his stomach. Also known as a “wind sucker” when a horse sucks air without grasping an object between his teeth.

crop: 1) the number of foals by a sire in a given year. 2) a group of horses born in the same year. 3) a jockey’s whip.

cryptorchid: a “unilateral cryptorchid” is a male horse of any age that has one testicle undescended. A “bilateral cryptorchid” is male horse of any age that has both testicles undescended.

cup: concavity in the occlusal surface of the tooth (the surfaces that meet when a horse closes its mouth) in young horses. It is used as a visual aid in determining the age in a horse. Also known as the infundibulum.

curb: 1) a thickening (strain) of the plantar ligament of the hock that causes an enlargement on the back of the hind cannon region just below the point of the hock. 2) Also, a type of bit.

Cushing’s disease: a hormonal disease due to a pituitary gland tumor. It causes a variety of problems which can include diabetes-like syndrome; weight loss; chronic laminitis and a long, shaggy, curly hair coat that fails to shed. There is no cure, but in some cases the signs can be lessened by administration of medications to suppress overproduction of certain hormones, and stimulate production of the neurotransmitter dopamine.

cut down: horse suffering from injuries from being struck by the shoes of another horse. Or, due to a faulty stride, a horse may cut itself down.

cyst: an enclosed, smooth lump with a solid or liquid center produced by the cells lining the cyst’s wall. Cysts generally do not cause problems unless their location and size are in the path of tack or interfere with function of adjacent parts. Treatment options may include surgical removal, cryosurgery, cauterization or obiteration by laser. When a fluid-filled cyst is simply drained, it usually refills within a few days.



dam: the female parent of a foal.

dam’s sire (broodmare sire): the sire of a broodmare. Used in reference to the maternal grandsire foal.

dark bay or brown: a horse color that ranges from brown with areas of tan on the shoulders, head and flanks, to a dark brown, with tan areas seen only in the flanks and/or muzzle. The mane, tail and lower portions of the legs are always black unless white markings are present.

deep digital flexor tendon: present in all four legs, but injuries most commonly affect the front legs. Located on the back (posterior) of the front leg between the knee and the foot and between the hock and the foot on the rear leg. The function is to flex the digit and fetlock and support the lower limb as part of the suspensory apparatus. In the front limb it also flexes the knee (carpus) and extends the elbow. On the rear leg, it also extends the hock. Functions in tandem with the superficial flexor tendon.

degenerative joint disease: any joint problem that has progressive degeneration of joint cartilage and the underlying (subchondral) bone. Also called osteoarthritis, a severe form of arthritis that has a progressive degeneration of joint cartilage. Occurs most frequently in the joints below the radius in the foreleg and the femur in the hind leg. Some of the more common causes include repeated trauma, conformation faults, blood disease, traumatic joint injury, subchondral bone defects (OCD-osteochondritis dessicans-lesions) and repeated intra-articular corticosteroid injections.

desmitis: inflammation of a ligament. Involves tearing of ligament fibrils. The number of torn fibrils determines the severity of the injury.

deworming: the use of drugs (anthelmintics) to kill internal parasites, often performed by administration of oral paste or by passing a nasogastric tube into the horse’s stomach.

digestible energy: the amount of energy the horse is able to digest from feedstuff.

digit: the part of the limb below the fetlock (ankle) joint. Includes the long and short pastern bones, the coffin bone and the navicular bone.

digital cushion: thick elastic tissue lying under the frog and separating it from the coffin bone. It serves as a shock absorber.

distaff: a female horse.

distal sesamoidean ligaments: attach the bottom of the sesamoid bones to the long and short pastern bones.

distal: away from the center of the body. Usually refers to the limbs. The injury was distal to (below) the hock .

DMSO: dimethyl sulfoxide, a topical anti-flammatory.

dorsal displacement of the soft palate: a condition in which the soft palate, located on the floor of the airway near the larynx, moves up into the airway. A minor displacement causes a gurgling sound during exercise while in more serious cases the palate can block the airway. This is sometimes known as “choking down” or “swallowing the tongue” but the tongue does not actually block the airway. The base of the tongue is connected to the larynx, of which the epiglottis is a part. When the epiglottis is retracted, the soft palate can move up into the airway (dorsal displacement). This condition can sometimes be managed with equipment such a figure eight noseband or a tongue-tie. In more extreme cases, surgery might be required, most commonly a “myectomy” (excision of the muscles that retract the larynx).

dorsal: toward the back or spine of the horse (upwards). Also, used to describe the front surface of the lower limb below the knee (front limb) or hock (rear limb).

drench: liquid (usually medication) administered through the mouth.

driving: a horse that is all out to win and under strong urging from its rider.

DVM: Doctor of Veterinary Medicine.

dysphagia: difficulty swallowing, which can be due to pain, obstruction (choke) or a problem with the nerves that govern throat muscles. The most common signs of dysphagia are slobbering of food from the mouth and/or drainage of chewed food and saliva from nostrils. Treatment usually is aimed at identifying and resolving the underlying cause and adjusting feeding methods (e.g. feeding by stomach tube) to avoid aspiration pneumonia.



ear mites: infestation by parasites that have invaded the horse’s ear canal, causing inflammation, itching and increased wax formation. Signs can include head shaking and holding the ear drooped to one side. Treatment is generally aimed at killing the mites with insecticides and cleaning the ear of wax and debris that resulted from inflammation. (Sedation usually is needed to accomplish this).

earmuffs: a piece of equipment that covers a horse’s ears to prevent it from hearing distracting sounds or having insects bother its ears.

Eastern Equine Encephalomyelitis (EEE): viral infection of the horse’s brain and spinal cord, which can infect horses, humans and selected birds, transmitted by mosquitoes. Signs can include behavioral changes, loss of appetite and fever. These can progress in 12 to 24 hours to dementia with head pressing, teeth grinding, circling and often blindness. The disease is fatal in up to 90 percent of cases. Surviving horses often have residual mental dullness. Treatment is generally supportive.

EEE (Eastern Equine Encephalomyelitis): one of several contagious types of encephalomyelitis that causes sickness and death in horses by affecting the central nervous system. EEE is spread by mosquitoes and can affect humans. Can be prevented through annual vaccinations.

EIA: Equine Infectious Anemia. A contagious disease characterized by an intial acute attack of fever, weakness to the point of incoordination and jaundice, as well as other signs. Ensuing attacks result in anemia, emaciation and cardiac insufficiency. It is spread by biting flies and mosquitoes.

EIPH: Exercise-induced pulmonary hemorrhage. See bleeder.

ELISA: Enzyme Linked Immunosorbant Assay. A form of testing to determine levels of medication existent in the fluids of horses.

encephalitis: inflammation of the brain, usually due to infection.

endometritis: inflammation of the uterine lining, usually due to infection.

endoscope: an instrument used for direct visual inspection of a hollow organ or body cavity such as the upper airway or stomach. A “fiberoptic endoscope” is comprised of a long, flexible tube that has a series of lenses and a light at the end to allow the veterinarian to view and photograph the respiratory system by insertion through the nostrils and air passageways. Other internal organs may be viewed by inserting the endoscope through a surgical opening. A “video endoscope” has a small camera at the tip of the instrument.

endotoxemia: blood poisoning that can occur with such serious conditions as Potomac horse fever, colitis, grain overload, severe colic, Salmonella infection, respiratory tract infection or uterine infection. As bacteria die a natural death, they release a miniscule amount of toxin that has no effect on the horse unless the bacteria are present in larger-than-usual numbers. In such a case, the dose of toxin the horse absorbs can cause endotoxemia. This condition is the biggest killer of horses from non-traumatic causes, and is the cause of death in most fatal colics.

endotoxin: a substance produced by bacteria that, when absorbed into the horse’s body, can cause endotoxic shock.

enterolith: a “stone” in the horse’s intestinal tract, made of minerals present in the feed and/or intestinal secretions, and usually formed around a foreign body, such as a small piece of debris. Small, pebble-like enteroliths can be swept out with the manure, or can remain in the intestinalo tract where they grow larger, later interfering with manure passage. Treatment often includes removal by surgery. If enteroliths are small enough, removal by regular administration of a bulk laxative can be used. Dietary changes may also be prescribed.

entire: an ungelded horse.

entrapped epiglottis: a condition in which the thin membrane lying below the epiglottis moves up and covers the epiglottis. The abnormality may obstruct breathing. Usually treated by surgery to cut the membrane if it impairs respiratory function.

epiglottis: a triangular-shaped cartilage that lies at the base of the airway just in front of the arytenoids cartilages. It covers the airway during swallowing to prevent the entry of foreign bodies. It is normally located above (dorsal to) the soft palate.

epistaxis: see bleeder.

EPM: infection of the brain and spinal cord by a protozoan called Sarcocystis neurona.The protozoa are spread by the definitive host the opossum, which aquires the organism from scavenging carcasses of cats, raccoons, skunks, armadillos and possibly even from harbor seals and sea otters. Horses become infected by eating on contaminated areas where opossums droppings are present. Signs can vary widely and may include weakness, staggering, head tilt, dysphagia and/or seizures. Diagnosis is based on symptoms and spinal tap of the horse.

equine influenza: a contagious viral disease of the upper respiratory tract. Symptoms may include cough, fever, muscle soreness and nasal discharge. Treatment is generally supportive. Rest until at least two weeks after the cough has resolved is an important component of successful treatment, since premature return to work can prolong the cough. Vaccination is the most effective means of prevention.

equine viral arteritis (EVA): a contagious viral disease spread by casual contact or by breeding with a previously infected mate. If mares are infected while pregnant, they will usually abort. Affected horses are sick and contagious for a week to 10 days with flu-like symptoms. Most victims recover completely with proper nursing care (but can spread the disease to others after recovery, via sexual contact).

equipment: see bandage; bar shoe; bit; blinkers; bridle; earmuffs; halter; hood; nose band; overgirth; reins; saddle cloth; saddle pad; shadow roll; shank; stirrups, breast plate; foregirth; martingale.

estrous cycle: the length of time between consecutive ovulations.

estrus (heat): associated with ovulation; a mare usually is receptive to breeding during estrus. The mare’s behavior at this time is referred to as “horsing.”

euthanasia: elective termination of the horse’s life for humane reasons.

EVA (equine viral arteritis): a highly contagious disease that is characterized by swelling in the legs of all horses and swelling in the scrotum of stallions; can cause abortion in mares and can be shed in the semen of stallions for years after infection.

extensor tendon: tendon of a muscle that extends the knee (carpus) joint.



farrier: horseshoer.

fetlock (joint): joint located between the cannon bone and the long pastern bone, equivalent to the human knuckle but often referred to as the “ankle.”

fiber optic endoscope: see endoscope.

figure-eight noseband: see noseband.

filly: female horse four years old or younger. The age in Quarter horses is three years old and younger.

firing: see pin firing.

Firm (track): a condition of a turf course corresponding to fast on a dirt track. A firm, resilient surface.

fissure (fracture): longitudinal crack through only one surface of a bone.

fistulous withers: a deep infection at the withers, possibly due to a contusion-type injury from poor-fitting tack, followed by a break in the skin through which damaged tissues become contaminated. Signs may include swelling, heat, pain and discharge of pus and debris through draining tracts. Treatment, which is done cautiously to avoid human infection, generally focuses on debridement and disinfection of contaminated tissues. In some cases, administration of systemic antibiotics is performed.

flack jacket: similar to a jacket worn by a quarterback, the rider’s flak jacket protects the ribs, kidneys and back.

flat race: contested on a level ground without a jumping component as opposed to a steeplechase. Often used in the term, on the flat.

float: 1) v. an equine dental procedure in which sharp points on the teeth are filed down. 2) n. the instrument in which the above procedure is performed.

foal: 1) a horse of either sex in its first year of life. 2) as a verb, to give birth.

footing: the surface upon which the horse performs.

founder: see laminitis.

fracture: a break in a bone. See comminuted; compound; condylar;fissure; metacarpal;oblique;saucer; sesamoid; slab; spiral; simple; stress.

frog: the V-shaped, pliable support structure on the bottom of the foot.

full brother, full sister: horses that share the same sire and dam.

furlong: one-eighth of a mile; 220 yards; 660 feet.

furosemide: a medication for the treatment of bleeders, commonly known under the trade name Salix. Furosemide is primarily a diuretic, but has also been shown to reduce hypertension (high blood pressure) in the horse’s lung.




“grab a quarter”: injury to the back of the hoof or foot caused when the hind hoof steps on the front hoof. Also known as “overreaching.”

gait: the characteristic footfall pattern of a horse in motion. Four natural gaits are performed by all horses: walk, trot, canter and gallop. Some horses also perform other gaits, such as the pace, running walk, rack, etc.

gastric ulcer: ulceration of a horse’s stomach. Often causes symptoms of abdominal distress (colic)

gelding: a male horse of any age that has been neutered by having both testicles removed (“gelded”).

get: progeny of sire.

girth: an elastic and/or leather band, sometimes covered with sheepskin, that passes under a horse’s belly and is connected to both sides of the saddle.

granddam: see second dam.

grandsire: the grandfather of a horse; father (sire) of the horse’s dam or sire.

gravel: infection of the hoof resulting from a crack in the white line (the border between the insensitive and sensitive laminae). An abscess usually forms in the sensitive structures, and may eventually break at the coronet as a result of the infection.

gray: a horse color where the majority of the coat is a mixture of black and white hairs. The mane, tail and legs may be either black or gray unless white markings are present.

greasy heel, grease heel: a severe, deep skin infection on the backs of the horse’s pasterns. The bubbly-looking skin growth creates deep crevices for the infective organism to escape topical treatments. This condition usually involves two or more feet, most often the hind feet. Successful treatment typically requires aggressive debridement, with twice daily cleansing and disinfection of remaining tissues. The horse should be housed in an area that’s dry and clean. Systemic antibiotics may be warranted if the specific infective bacteria are identified via culture.

green osselet: in young horses, a swelling in the fetlock joint, particularly on the front of the joint where the cannon and long pastern bones meet. This swelling is a result of inflammation and reactive changes of the front edges of these two bones. If the green osselet does not heal, a “chronic osselet” might develop with a permanent build-up of synovial fluid in the joint and inflammation and thickening of the joint capsule over the damaged area, with secondary bone changes following the initial inflammation.

groom: a person who cares for a horse in a stable.

growth plates: located near the end of long bones where they grow in length. See physis.

grullo: body color in American Quarter horses smoky or mouse-colored (not a mixture of black and white hairs, but each hair mouse colored); mane and tail black; usually has black dorsal stripe and black on lower legs.

guttural pouch: an air-filled pouch in the throat region that may become infected. The pouch is part of the Eustachian tube, a passage between the pharynx and the middle ear, and is unique to the horse.



half-brother, half sister: horses out of the same dam but by different sires. Horses with the same sire and different dams are not considered half-siblings.

halter: like a bridle, but lacking a bit. Used in handling horses around the stable and when they are not being ridden.

hand gallop: a gallop of moderate speed.

hand ride: urging a horse with the hands and not using the whip.

hand: four inches. A horse’s height is measured in hands and inches from the top of the shoulder (withers) to the ground, e.g. 15.2 hands high is 15 hands 2 inches. Thoroughbreds typically range from 15 to 17 hands.

harrow: implement or unit with pulling teeth or tines used to rake and loosen the footing in an area.

heaves: emphysema.See chronic obstructive pulmonary disease.

heel crack: a crack on the heel of the hoof. Also called a “sand crack.”

helmet: shock-absorbing head gear worn by riders to prevent head injuries.

hematoma: a blood-filled area resulting from injury.

hock: a large joint just above the cannon bone in the rear leg that corresponds to the level of the knee of the front leg. Equivalent to the human ankle joint.

homebred: a horse bred by his owner.

hoof: the foot of the horse. Consists of several parts that play an integral role in supporting the weight of the horse.

horse: when reference is made to sex, a “horse” is an ungelded male five years old or older (i.e., a stallion).

horsing: behavior of a mare in heat (in season). See estrus.

Hyaluronic acid: a normal component of joint fluid. Also can be manmade intra-articular medication used to relieve joint inflammation (Adequan™ or Legend™).

Hyperkalemic periodic paralysis (HYPP): an inherited disorder of certain lines of Quarter horses, most noticeably those related to the late halter stallion Impressive. Affected horses seem normal between attacks. These can be mild or severe, and last from a few minutes to several hours, and seem to be triggered by work stress, anxiety, cold, and/or eating a diet high in potassium. Signs may include occasional skin rippling, localized muscle twitching, violent body-wide tremors, sweating, panting, passing loose manure, hindlimb weakness and collapse. Sever episodes can be fatal due to heart failure. Diagnosis is confiemed through genetic blood testing. There is no cure, but frequency and severity of attacks can be reduced with careful management and diet adjustment to reduce potassium levels.




icing: 1) a physical therapy procedure, properly known as “cryotherapy.” 2) when a horse stands in a tub of ice or when ice packs are applied to the legs to reduce pain and/or swelling.

icterus: yellow discoloration of skin and mucus membranes (gums, eyelid rims, inner surface of vulva) due to accumualtion of pigments normally metabolized by the horse’s liver. Causes can include liver disease, hemolytic anemia, snakebite, ingestion of certain potential toxins such as red maple leaves, onions, or phenothiazine drugs and fasting. Treatment usually is focused on addressing the underlying problem.

identification: involves a system of recognition of several types of markings by the horse identifier. Marking’s are noted on an animal’s breed registry papers and usually range from coat color, lip tatoos, hair whorls, cowlicks, white markings, night eyes, scars and brands.

IgG: Immunoglobulin.

IM: abbreviation for intramuscular, an injection given in a muscle.

impaction: a type of colic caused by a blockage of the intestines by ingested material. Constipation.

in foal: pregnant mare.

in the bridle: see on the bit.

inferior check ligament: a ligament that runs from the back of the knee or the hock to the deep digital flexor tendon.

influenza: a viral infection that causes a highly contagious upper-respiratory disease. Signs can include fever, dry cough, watery nasal discharge, decreased appetite, muscle soreness, enlarged lymph nodes and swollen legs. The rule of thumb is to rest a minimum of three weeks, or one full week for every day the horse had a fever, whichever is longer. Influenza vaccine is usually recommended up to four times per year, depending on the incidence of the disease and the horse’s exposure to other horses.

insensitive laminae: the layer just under the wall of the hoof; similar to the human fingernail. It is an integral structure that helps to attach the hoof wall to the underlying coffin bone.

intra-articular: within a joint.

irons: see stirrups.

ischemia: a deficiency of blood supply that may be temporary or permanent. Caused by shutting down of the blood vessels.

isolation barn: a facility used to separate sick horses from healthy ones.

IV: abbreviation for intravenous; an injection given in the vein.




jack spavin: see bone spavin.

jog: slow, easy trot.

joint capsule: the structure that encloses the joint space.

joint: see musculoskeletal system.

jumper: steeplechase or hurdle horse.

juvenile warts: pink or brown, fleshy, hairless growths, usually on the muzzle or elsewhere on the face of young (less than 3-years-old) horses. Believed to be caused by a contagious virus, juvenile warts tend to run their course and disappear suddenly after being present a few weeks to several months. It’s believed that the positive response to various home remedies is merely coincidence – the warts were going to resolve anyway.

juvenile: two-year-old horse.



kissing spines, overriding dorsal spinous processes: a touching or overriding of the vertical (dorsal) spinous processes of the vertebrae. The primary sign generally is pain on palpation over the backbone and the long muscles beside it. Depending on the location and extent of the problem, the horse’s gait may be restricted. Treatment options may include rest, injection of the area with medication to block inflammation and pain, acupuncture, ultrasound or surgery.




lactic acid: organic acid normally present in small amounts in muscle tissue, produced by anaerobic muscle metabolism as a by-product of exercise. An increase in lactic acid occurs during exercise. A large accumulation causes muscle fatigue, inflammation and pain.

lameness: a deviation from a normal gait due to pain in a limb or its supporting structure.

laminae: a part of the hoof. See insensitive laminae and sensitive laminae.

laminitis: an inflammation of the sensitive laminae of the foot. Many factors are involved, including changes in the blood flow through the capillaries of the foot. Causes include ingesting toxic levels of grain, eating lush grass, systemic disease problems, high temperature, toxemia, retained placenta, excessive weight-bearing as occurs when the opposite limb is injured, and the administration of some drugs. Laminitis usually manifests itself in the front feet, develops rapidly, and is life threatening, although in mild cases a horse can resume a certain amount of athletic activity. Laminitis caused the death of Secretariat.

laser (or cold laser): a low-intensity focused beam of light used to reduce inflammation and promote circulation.

lateral: toward the side and farther from the center. Pertains to a side.

lathered (up): see washed out.

lead: 1) see shank. 2) the front leg that is last to hit the ground during a gallop or canter stride.

left laryngeal hemiparesis: when the vocal fold or arytenoids cartilage on the left side of the airway becomes partially or totally paralyzed and interferes with air flow. Causes a whistling or “roaring” noise during inspiration when the horse exercises. See roaring.

ligament: a band of fibrous tissue connecting bones that supports and strengthens the joint and limits the range of motion.

lunge: a method of exercising a horse on a tether (“lunge line”).

Lyme disease: infection with the spiral-shaped bacteria Borrelia burgdorferi, spread by the bite of an infected tick. Signs may vary widely and can include recurrent lameness that shifts from one leg to another and for which no other cause can be found, arthritis, stiffness and reluctance to move. Treatment is usually administration of antibiotics from the penicillin or tetracycline family.




magnetic therapy: physical therapy technique using magnetic fields to create a low energy electrical field. It causes dilation of the blood vessels (vasodilation) and tissue stimulation. Magnetic therapy may be used on soft tissue to treat such injuries as tendonitis or bony (skeletal) injuries such as bucked shins.

maiden: 1) a horse or rider that has not won a race. 2) a female horse that has never been bred.

malignant: referring to a cancerous growth: locally invasive and destructive, and/or tending to spread to other areas of the body.

mare: female horse five years old or older. In American Quarter horses, four and older.

martingale: piece of tack used to help the rider maintain control in horses that evade the action of the bit by raising their head.

mash: soft, moist mixture, hot or cold, of bran, grain and other feed that is easily digested by horses.

massage: rubbing of various parts of the anatomy to stimulate healing or relaxation.

medial: pertaining to the middle in anatomy, nearer the media plane (the vertical plane that bisects the center) of the body when viewed from in front or behind.

melanoma: usually firm, smooth, hairless black nodules relatively common in gray horses, most often found u der a horse’s tail, around his ear and on his face near the main joint of his jaw. Some can grow aggressively, causing erosions and spreading to adjacent lymph nodes and lungs. Most melanomas grow slowly and are benign (don’t tend to spread to other organs). Treatment is seldom recommended, as external melanomas often return after surgical removal.

metacarpal: usually refers to a fracture of the cannon bone, located between the knee and the fetlock joint in the front leg. Also, may refer to a fracture of the splint bone.

mid-body (fracture): see sesamoids.

midges, no-see-ums: tiny flies of the Culicoides family, considered responsible for the warm-weather skin allergy called Sweet itch.

monorchid: a male horse of any age that has only one testicle in his scrotum; the other testicle was either removed or is undescended. See cryptorchid; ridgling.

moon blindness: a disease of the uvea (the colored iris) inside the eyeball. The uvea becomes inflamed (uveitis), which causes its muscles to spasm, thereby constricting the pupil. Eye pain from uveitis is severe and can cause squinting, tearing, excessive blinking and dangerous eye rubbing (increasing the risk of eye trauma). If not resolved, uveitis can result in permanent blindness. Treatment can include topical and systemic medication to relieve pain and inflammation, relax the spasming and combat possible infection.

musculoskeletal system: consisting of the bones, muscles, ligaments, tendons and joints of the head, vertebral column and limbs, together with the associated muscles, tendons, ligaments and joints.

muzzle: 1) nose and lips of a horse. 2) a guard placed over a horse’s mouth to prevent it from biting or eating.




nasogastric tube: a long tube that is capable of reaching from the nose to the stomach used to administer medications.

navicular bone: a small, flat bone within the hoof that helps, along with the short pastern bone and the coffin bone, to make up the coffin joint.

navicular disease: a degenerative disease that affects the navicular bone (small bone in the back of the foot), navicular bursa and deep digital flexor tendon. Generally considered a disease of the front feet. Both front feet are often affected, but one will usually be more noticeable than the other.

near side: left side of a horse; side on which a horse is mounted.

nerve block: injection of local anesthetic in the vicinity of a specific nerve to deaden the region for which that nerve provides sensation and motor function. Nerve blocks are used to diagnose lameness, to allow pain-free surgery on an awake patient, to paralyze specific body parts (e.g. to paralyze a wounded eyelid so it will hold for repair) and to relax internal muscles. Depending on the local anesthetic used, effects can last from 20 minutes to eight hours.

neurectomy: a surgical procedure in which the nerve supply to the navicular area is removed. The toe and remainder of the foot have feeling. Also referred to as “posterior digital neurectomy” or “heel nerve.”

night blindness: an inherited vision problem that, although present at birth, might not be noticed until later in life. Signs can include reluctance to move when it’s dark, head cocking as though trying to hear what can’t be seen, star gazing and a cross-eyed appearance when viewed from the front. There is no known treatment.

night eyes: see chestnuts.

non-sweater: see anhydrosis.

noseband: a leather strap that goes over the bridge of a horse’s nose to help secure the bridle. A dropped noseband, flash noseband and figure-eight (or grackle) noseband have a strap that fits under the rings of the bit to prevent the horse from resisting the action of the bit by opening its mouth. This keeps the tongue from sliding over the bit.




oblique (fracture): fracture at an angle to the shaft of the bone.

OCD (osteochondritis desicans) lesion: a cartilaginous or bony lesion that is the result of a failure in development.

off side: right side of horse.

oiled (oiling): administering mineral oil via nasogastric tube to help relieve gas or pass blockage. Preventive procedure commonly used in long van rides to prevent impaction colics. See colic.

on the bit: refers to carriage of the horse in which the neck and back are rounded, the hind legs are well engaged and the horse is obedient to the action of the bit. Also known as “in the bridle”.

on the muscle: denotes a fit horse.

open fracture: see compound fracture.

osselets: see arthritis.

osteoarthritis: a severe form of arthritis that has a progressive degeneration of joint cartilage. Occurs most frequently in the joints below the radius in the foreleg and the femur in the hind leg. Some of the more common causes include repeated trauma, conformation faults, blood disease, traumatic joint injury, subchondral bone defects (OCD) lesions and repeated intra-articular corticosteroid injections. A permanent form of arthritis with progressive loss of the articular cartilage in a joint. See degenerative joint disease.

over at the knee: type of conformation in which the front leg looks like it has a forward arc with the center at the knee when viewed from the slide.

overcheck: a strap that holds the bit up in the horse’s mouth.

overgirth: an elasticated strap that goes completely around a horse over the saddle, to keep the saddle from slipping.

over-reaching: toe of hind shoe striking the forefoot or foreleg.





P3: third phalanx. See coffin bone.

paddle: type of movement in which the lower front leg swings outward. Often associated with toe-in conformation.

paint: counter-irritant used to increase blood supply and blood flow and to promote healing in the leg. A mild form of blistering.

palmar: back of front limb from knee down.

parrot mouth: an extreme overbite.

pastern: the area between fetlock joint and hoof. It comprises the long (P1) and short (P2) pastern bones and the pastern joint.

pedal bone: see coffin bone.

pemphigus foliaceus: a skin disorder caused by the body’s immune system mistakenly attacking some of its own cells involved in skin production. Signs may include the formation of blisters and pustules that break open and form crusted sores. Lesions generally start on the horse’s face and limbs, eventually spreading to the rest of the body. There is no cure, but treatment can control the lesions and cause the disorder to go into remission. Treatment may involve suppression of the immune system by administration of systemic corticosteroids.

periostitis: inflammation of tissue (periosteum) that overlies bone. Periostitis of the cannon bone is referred to as bucked shins, while periostitis of the splint bone is called a splint. May be heard in the expression “Popped a splint.”

phenylbutazolidan: see bute.

phenylbutazone: see bute.

physis (plural, physes): the “growth plate” at the end of the long bones (such as the cannon bone) that lets the bone grow.

physitis: an inflammation in the growth plate (physis) at the ends of the long bones (such as the cannon bone) in young animals. Symptoms include swelling, tenderness and heat. Although the exact cause is unknown, contributing factors seem to be high caloric intake (either from grian or a heavily lactating mare) and a fast growth rate.

pigeon fever: infection of a bacteria, causing one or more lumps beneath the skin the horse’s brisket and lower abdominal area. Treatment may include the application of hot packs and/or poultices to draw out infection and/or lancing the abscesses. Antibiotics may also be prescribed after abscesses have been lanced.

pin firing: thermocautery used to increase blood flow to leg, thereby promoting healing.

pinhooker: a person who buys horses, cattle, etc. with the specific intention of re-selling it at a profit.

pipe-opener: exercise at brisk speed.

Piroplasmosis (or equine babesiosis, “piro” or horse tick fever): a tick-borne disease caused by blood parasites. Acute signs include fever, anemia, jaundice and swelling of the legs, chest and abdomen. The disease is ultimately resolved through treatment, natural body defenses or death. Horses in the United States are largely unexposed and are therefore susceptible to the disease, while many European horses are symptomatic carriers.

plantar: back of the hind limb from the hock down.

poll: the top of the head, between the ears.

polysulfated glycosaminoglycan (PSGAG): an anti-inflammatory agent used by intra-articular injection in the therapy of traumatic and degenerative arthritis in horses.

popped a splint: see periostitis.

posterior: situated toward the rear of the horse’s body.

Potomac Horse Fever (PHF): protozoal infection of the intestinal tract usually causing diarrhea, fever, depression and colic. Treatment is generally supportive and administration of appropriate antibiotics, along with preventive measures to avoid the development of laminitis, a common sequel to PHF.

poultice: a soft, mushy dressing, made of a mixture of dry, absorbent substances with liquid or oil, applied to wounds or swellings to soften, relax or stimulate the tissues or reduce swelling.

prep: a workout used to prepare a horse for a competition.

prop: when a horse suddenly stops moving by digging its front feet in to the ground.

proud flesh: an overgrowth of pink, bubbly-looking tissue during healing of certain flesh wounds. It can protrude from the injury site like a tumor, preventing new skin from covering the wound. Treatment depends on location and severity, and will usually include one or more of the following: topical application of various medications designed to melt away the excessive tissue, pressure bandages and/or surgical removal of proud flesh.

pull up: to stop or slow a horse during a workout.

pulled suspensory: strain of the suspensory ligament (suspensory desmitis) in which some portion of the fibers of the ligament have been disrupted. Depending on severity, there may be loss of support of the fetlock joint.




quarantine barn: 1) a U.S. Department of Agriculture structure used to isolate foreign horses for a short period of time to ensure they are not carrying any disease. The structure may be at a racetrack, airport or specially designated facility. Horses must be cleared by a federal veterinarian before being released from quarantine. 2) any facility used to keep infected horses away from the general equine population.

quarter crack: a vertical crack in the hoof wall between the toe and heel of the hoof, usually extending into coronary band.

Quarter Horse: American Quarter Horse, preferred terminology of the American Quarter Horse Association, the registering body. Descended from Thoroughbreds and Spanish Barb bloodlines, the quarter horse is the most popular breed in the world with more than three million horses registered. It excels at virtually every equestrian sport and is known for its innate “cow sense,” making it the ideal ranch horse.

quicked: a horse is “quicked” when a hoof is trimmed too short or when a horseshoe nail is driven into the quick or sensitive lamina of the hoof. In many cases, the horse flinches or pulls back when the quick occurs. Within a few days, some cases develop tenderness and mild to moderate lameness due to developing infection in the area. Treatment involves removal of the offending nail, if applicable, cleansing the hole and application of a poultice to draw out remaining contamination.

quidding: the spitting out of partially chewed wads of food. Quidding is a sign of a dental problem and/or difficulty swallowing.




radiograph: the picture or image on film generated by X-rays.

rainrot: a crusting skin disorder affecting your horse’s saddle area, with tufts of crusted-together hair easily pulled out, leaving a raw crater. The causative organism, which has characteristics of both bacteria and fungi, tends to thrive in wet weather when the skin is waterlogged and less capable of fighting infection. It can spread to other horses by the use of contaminated grooming tools. Treatment usually is softening and removal of scabs, disinfection of affected area with iodine or chlorhexidine-based shampoos or rinses, strict hygiene and provision of dry shelter and disinfection of grooming tools. Severe or persistent cases might also be treated with systemic antibiotics.

RBC: Red Blood Cell Count

recumbent: lying down, reclining.

red roan: more or less uniform mixture of white with red hairs on a large portion of the body of the American Quarter horse, but ususally darker on head and lower legs; can have red, black or flaxen mane and tail.

reins: long straps, usually made from leather, that are connected to the bit and used by the rider to control the horse.

reserve: a minimum price, set by the consignor, for a horse in a public auction.

respiratory system: organ system responsible for transporting air from nostrils to lungs and for absorption of oxygen and excretion of carbon dioxide.

ride short: using short stirrups.

ridgling (“rig”): a term describing either a cryptorchid or a monorchid. Also spelled “ridgeling.”

ring bone: osteoarthritis of joints between the pastern bones (“high ring bone”) or just above the coronet (“low ring bone”).

ringworm: a fungal infection of the horse’s skin, contagious to other horses and to other animals (including humans). The main sign of ringworm is patchy hair loss without itching. Treatment can include clipping hair from affected areas, daily bathing with iodine-based shampoo, possible application of topical antifungal preparations after each bath, strict maintenance of dry shelter and exposure to sunlight whenever possible. For severe cases, oral administration of anti-fungal medications may be necessary.

roan: a horse color where the majority of the coat of the horse is a mixture of red and white hairs or brown and white hairs. The mane, tail and legs may be black, chestnut or roan unless white markings are present.

roaring (laryngeal hemiplegia): a whistling sound made by a horse during inhalation while exercising. It is caused by a partial or total paralysis of the nerves controlling the muscles that elevate the larynx. In severe cases, a surgical procedure known as laryngoplasty or “tie back surgery” is performed, in which a suture is inserted through the cartilage to hold it out of the airway permanently. Paralysis almost exclusively occurs on the left side, most frequently in horses over 16 hands high.

rogue: ill-tempered horse.

run down: abrasions of the heel.




tack: 1) a rider’s equipment. 2) As a verb, including his/her equipment as in: He tacks his horse each day.

Tagamet™: trade name for the drug cimetidine, a medication used to treat ulcers.

tattoo: a permanent, indelible mark on the inside of the upper lip used to identify racehorses.

teaser: a male horse used at breeding farms to determine whether a mare is ready to receive a stallion.

tendinitis: inflammation of a tendon, usually due to injury. Signs generally include swelling and heat over affected tendon, pain on finger pressure, lameness and a protective stance to limit tendon stress. Treatment may include aggressive first aid to limit swelling and hemorrhage between tendon fibers, enforced rest, immobilization of the tendon, administration of anti-inflammatory medications and physical therapy to limit formation of adhesions.

tendon sheath: sheath containing synovial fluid that surrounds a tendon in a high-friction area, usually where a tendon runs over a bone.

tendon: cords of strong, white, collagen fibers that connect a muscle to a bone or other structure and transmit the forces generated by muscular contraction to the bones.

tendonitis: inflammation of a tendon usually due to tendon fiber disruption.

tetanus antitoxin: antitoxin is a product made from blood serum containing antibodies against a specific toxic (poison). Tetanus antitoxin is made of equine serum and contains antibodies against the tetanus toxin.

tetanus toxoid: a toxoid is a vaccine made of toxin (poison) that has been altered chemically so that it has no toxic effects, but is able to stimulate immune response. Tetanus toxoid is a vaccine that stimulates the horse’s body’s production of antibodies against the toxins that cause tetanus.

tetanus: a disease resulting from toxins produced by bacteria, usually resulting when they infect a wound, particularly a deep puncture wound, where oxygen is scarce. Because this bacteria is present in the horse’s manure, they are ubiquitous in the soil on a horse property. Signs of tetanus may include elevation of both nictitating membranes when the horse’s face is tapped gently below the eye, spasms of the muscles in the jaw, making it difficult or impossible to eat or drink, a “sawhorse” stance with rigid legs, convulsions triggered by noise or other stimuli, profuse sweating and death. Treatment is usually aggressive debridement of the infected wound to prevent further toxin absorption, intravenous administration of tetanus antitoxin, administration of anti-seizure medications, sedatives and muscle relaxants and intensive supportive care including intravenous fluids and feeding a gruel via stomach tube.

therapeutic ultrasound: a therapy to create heat and stimulate healing.

thermography: diagnostic technique utilizing instrumentation that measures temperature differences. Records the surface temperature of a horse. Unusually hot or cold areas may be indicative of some underlying pathology (deviation from the normal.)

third phalanx(P3): see coffin bone.

Thoroughbred: A horse whose parentage traces to any of three “founding sires” (the Darley Arabian, Byerly Turk or Godolphin Barb) and who satisfies the rules and requirements of The Jockey Club and is registered in “The American Stud Book” or in a foreign stud book recognized by The Jockey Club and the International Stud Book Committee.

thoroughpin: swelling in the tendon sheath of the deep digital flexor tendon above the hock.

thrush: a bacterial infection of the frog and/or adjacent crevices of the foot’s sole, causing a blackish discharge and foul odor. Treatment generally includes trimming and debridement of affected tissues, disinfection with copper sulfate, tincture of iodine (7 percent), or merthiolate, provision of dry clean environment, good hygiene and daily foot care.

thumps: see synchronous diaphragmatic flutter.

tie-back surgery: a procedure used to suture the arytenoids cartilage out of the airway as a treatment for roaring. Referred to as laryngoplasty. See roaring

tightener: a leg brace.

toe crack: a vertical crack in the hoof wall near the front of the foot.

toe-in: a conformation flaw in which the front of the foot is rotated inward and looks pigeon-toed. Often causes the leg to swing outward during locomotion (paddle).

toe-out: a conformation flaw in which the front of the foot is rotated outward. Often causes the leg to swing inward during locomotion (winging).

tongue tie: strip of cloth-type material used to stabilize a horse’s tongue to prevent it from “choking down” in a race or workout or to keep the tongue from sliding over the bit, rendering the horse uncontrollable. Also know as a “tongue strap.”

top line: 1) A horse’s breeding on its sire’s side 2) The visual line presented by the horse’s back.

torsion: a twist in the intestine.

toxemia: a poisoning sometimes due to the absorption of bacterial products (endotoxins) formed at a local source of infection.

TPR: Temperature, Pulse, Respiration.

tracheotomy: an artificial opening made in the windpipe (trachea) when a problem in the horse’s nasal cavity or throat has blocked the passage of air, making it impossible to breathe. Usually an emergency procedure.

transfaunation: administration of beneficial bateria to a horse suspected of intestinal disease due, at least in part, by disruption of the normal bacterial population in the gut.

trapped epiglottis: see entrapped epiglottis.

trot: a gait in which the legs on the same side of the horse’s body work in opposition; often described as the same motion a child makes when crawling on the floor.

tubing: inserting a nasogastric tube through a horse’s nostril and into its stomach for the purpose of providing oral medication.

twitch: a restraining device usually consisting of a stick with a loop of rope or chain at one end, which is placed around a horse’s upper lip and twisted. It causes a release of endorphins that relax a horse and curb its fractiousness while it is being handled.

tying up (acute rhabdomyolsis): a form of muscle cramps that ranges in severity from mild stiffness to a life-threatening disease. A generalized condition of muscle fiber breakdown usually associated with exercise. The cause of the muscle fiber breakdown is uncertain. Signs include sweating, reluctance to move, stiffness, and general distress.




ulcer: irritation in the lining of the horse’s stomach or intestine.

ultrasound: 1) a technique which uses ultrasonic waves to image internal structures such as soft tissues (tendons or ligaments).

untried: 1) not raced or tested for speed. 2) a stallion that has not been bred.

unwind: gradually withdraw a horse from intensive training. Let down.

upward fixation of the patella: locking of the hind limb in an extended, stretched-out position due to the medial patellar ligament (which holds the kneecap in place) getting hung on a notch at the end of the thigh bone (femur). In affected horses, the locking occurs suddenly and without warning. Intial treatment may include anti-inflammatory medication on the assumption that the ligament and/or adjacent tissues are inflamed and swollen. Muscle-building exercise such as hill work is often recommended to improve strength, and dietary adjustment is used if necessary to improve body condition. If these measures fail, stifle injections can be considered or surgery.

uveitis: inflammation and/or infection of the uvea, the colored iris of the horse’s eye. Signs may include constricted pupil, watery eye, squinting and rubbing. If allowed to progress, uveitis can lead to breakdown of the eye’s internal structures, detachment of the retina and blindness. Treatment includes frequent application of pupil-dilating ophthalmic medications as well as anti-inflammatory preparations such as dexamethasone or prednisone on the eye and/or systemically, systemic administration of nonsteroidal anti-inflammatory medications and detection and treatment of the underlying problem, if possible.



vasculitis: inflammation of small blood vessels and capillaries which, because of damage to their walls, leak serum into the tissues and cause swelling, most often in the horse’s lower legs. Treatment is generally aimed at cooling and soothing the swollen legs with gentle cold-water irrigation, and supporting the skin with padded compression bandaging to prevent splitting of the skin. If the skin has already split, the affected area usually is treated as a laceration.

VEE (Venezuelan Equine Encephalomyelitis): a highly contagious disease affecting the central nervous system. Can cause illness or death in horses and humans. Refer to EEE.

ventral: down; toward the belly or lower part of the body.

Vesicular Stomatitis: an acute viral disease that affects horses, cattle, swine, sheep, goats and wild animals. Humans who come in contact with fluids from infected animals’ blisters may also be affected. Human symptoms resemble the flu, including fever and muscle aches, and self-limiting blisters may appear on the hands and in the mouth. In animals, the first sign of VS is excessive salivation, followed by a fever and the appearance of blisters and/or whitened and raised vesicles in and around the mouth, nose, hooves and teats.

veterinarian: 1) Head of Veterinary Commission; 2) Veterinary Delegate; 3) Associate Veterinarian.

video endoscope: see endoscope.

vocal folds: the membranes attached to the arytenoids cartilages in the larynx. Vibration produces vocalization, i.e., whinny.




warmblood: genetic term used to describe distinct breeds usually named according to the region in which the breed was developed (e.g., Dutch Warmbloods from The Netherlands). Generally large, well-muscled horses with calm temperaments, making them suitable for dressage and show jumping.

washed out: a horse that becomes so nervous that it sweats profusely. Also known as “washy” or “lathered up.”

wave mouth: undulating surface of the grinder teeth due to uneven wear.

WBC: White Blood Cell Count.

weanling: a foal less than one year old that has been separated from its dam.

WEE: Western Equine Encephalomyelitis. Refer to EEE.

white line: when looking at the sole of the foot, the thin area between the insensitive outer hoof wall (insensitive laminae) and inner sensitive laminae.

white: a horse color, extremely rare, in which all the hairs are white. The horse’s eyes are brown, not pink, as would be the case for an albino.

wind gall: see arthritis. accumulation of synovial fluid in the fetlock joint or windgall in the tendon sheath of the digital flexor tendons just above the fetlock joint.

wind puff: see wind gall.

wind sucker: see cribber.

windpuffs: synovial effusion, with or without involvement of the adjacent tendon sheath, in the fetlock joint. This causes puffiness of the joint that might extend partway up the horse’s cannon bone. Windpuffs may or may not be associated with lameness. Causes can include excessive stress on joint soft tissues and tendons due to poor conformation, poorly balanced farriery, heavy training and/or sudden stall confinement after a period of regular training. Treatment generally focuses on identifying and correcting the underlying cause, rest, ice and pressure wraps to limit inflammation and sweeling.

withers: 1) area above the shoulder where the neck meets the back. 2) the horse’s height is measured at the highest point of the withers.

wobbler syndrome: 1) neurological disease associated with general incoordination and muscle weakness. 2) can be caused by injury to spinal cord in area of cervical (neck) vertebrae or is associated with malformation of the cervical vertebrae.

wolf teeth: the first premolars, located toward the back of the space between the horse’s front teeth and the grinders. When present on the lower jaw, wolf teeth are small and needle-like. When the presence, position and/or size of wolf teeth interfere with acceptance of the bit, the teeth are removed, usually with the horse awake and sedated.



xeroradiography: a costly type of x-ray procedure using specially sensitized screens that give higher resolution on the edges of bone and better visualization of soft tissue structures.



yearling: a horse in its second calendar year of life.



Zantac™: trade name for drug ranitidine, medication used to treat stomach ulcers.



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