GLOSSARY – EXAM 2

Action	The movement of the horse's legs.
A-equi-1, a-equi-2	Abbreviations for the two strains of the equine influenza virus.
Aged	A horse of 15 years of age or older. Prior to this age, experienced horsemen can estimate the age of a horse by examining the teeth.
Aging	The process of estimating the age of a horse by examining the appearance and development of the teeth.
Amble	The slower form of the lateral pacing gait. (See Pacer)
Amnion	The placental membrane immediately surrounding the foal.
Androgen	Male sex hormone; e.g., testosterone.
Anemia	Low red blood cell count, reduced hemoglobin levels, or reduced volume of packed red cells.
Anestrus	Period in the sexual cycle when the ovaries and uterus are less active and a mare
Anorexia	Loss of appetite; inappetence.
Anthelmintics	Any of various classes of drugs used to destroy internal roundworm parasites.
Anthropomorphic	Attributing human characteristics, particularly emotion and motivation, to animals.
Ascariasis	Any ascarid infestation.
Ascarid	A type of roundworm.
Asymptomatic	Not exhibiting clinical signs.
Bastard Strangles	Type of strangles that progresses from the head to the chest and abdomen, where it can form large and potentially fatal abscesses.
Binocular Fixation	The ability, particularly well developed in primates, to focus both eyes on a single object.
Bloodworms	Large Strongyles, so called because of their red color due to ingested blood.
Booster	Second or subsequent dose of an antigen to enhance immunity.
Bots	Equine parasite. The adults look like honey bees. They deposit little yellow eggs on the hairs of the legs and the larvae are ingested and burrow into the lining of the stomach.
Canter	Three beat gait of the horse in which one hind leg strides first (the leading leg), followed by the opposite diagonal pair and finally the opposite foreleg. Called the lope in Western riding.
Caps	Remnants of deciduous premolar teeth that are left behind when the permanent premolars erupt.
Cerebrospinal Fluid (Csf)	Fluid bathing the surfaces of the brain and spinal cord.
Cerebrum	Portion of the brain concerned with conscious thought, perceptions, and learned skills.
Cervix	Oval-shaped mass in the female reproductive tract whose opening connects the uterus with the vagina.
Cheek teeth	General term for the premolar and molar teeth.
Chronic Carrier State	Situation in which an animal or human being maintains (carries) an infectious disease agent for a prolonged period of time.
Coggins test	Laboratory blood test for the presence of antibodies against the equine infectious anemia.
Colic	Pain in the abdomen.
Collection	Where the rider, by means of carefully balanced driving and restraining aids, causes the horse's frame to become compacted and the horse light and supple in the hand. The baseline is shortened, the croup is lowered, the shoulder is raised and the head is held on the vertical.
Colostrom	First milk produced by a mare following foaling. Contains globulins to provide the newborn foal with temporary immunity against disease.
Corpus Luteum (Plural Corpora Lutea)	Ovarian follicle after discharge of the ovum (egg); it secretes the hormone progesterone.
Crib-Biting/Cribbing	A stable vice in which the horse hooks his teeth onto something solid, such as the door of his stable, and sucks air through his open mouth. Said to be addictive behavior, cribbing straps and collars have varying degrees of effectiveness at discouraging the behavior. Horses which suck air, without latching their teeth on to something are said to be wind sucking.
Cusps	The sharp points of the tooth crown.
Deciduous Teeth	"Milk teeth," the temporary teeth that are lost to make way for the permanent teeth.
Diagonal Gait	Each diagonal pair of limbs (off fore/near hind, near fore/off hind) move more or less together. A natural trot is a good example of a diagonal gait.
Diestrus	The quiescent period between one estrus period and the next; also called interestrus.
Distemper	Highly contagious disease caused by the bacteria Streptococcus Equi. More commonly known as Strangles.
Eastern Equine Encephalomyelitis	Contagious brain and spinal cord inflammation in horses, caused by a specific viral strain transmitted by mosquitoes. Characterized by fever, irrationality and or stupor, and almost always fatal.
Edema	The accumulation of abnormally large quantities of fluid in the intercellular tissue spaces (spaces between cells); pulmonary edema refers specifically to fluid buildup in the lungs
Encephalomyelitis	Inflammation of the white matter in the brain and spinal cord, often caused by a virus. The three primary strains of the virus are eastern, western, and Venezuelan.
Enamel Points	Sharp points that develop in the enamel of the teeth, owing to the normal positioning and growth of the teeth in the mouth; the sharp points can be ground down with a special instrument called a dental float
Endotoxins	Poisonous toxins produced within bacterial cells and released when those cells are destroyed.
EPM	Equine Protozoal Myleoencephalitis. Neurological disorder caused by a protozoa which invades the spinal cord, causing a variety of symptoms attributed to nerve damage - stumbling, loss of coordination, muscle atrophy, etc.
Equine herpes virus	Virus, which can cause Rhinopneumontis, abortion and possibly other disease in horses.
Equine Infectious Anemia (EIA)	One of the most important viral diseases of horses, caused by a retrovirus; it is a chronic infection resulting in a persistent (lifelong) carrier state with periodic exacerbations of anemic illness; also called swamp fever
Equine Influenza	Very important viral respiratory disease of horses caused by subtypes (A1 and A2) of equine influenza virus.
Equine Protozoal Myeloencephalitis	Inflammatory disorder of the brain and spinal cord, caused by a poorly characterized protozoan parasite tentatively designated Sarcocystis neurona
Equine Viral Encephalomyelitis	Inflammation of the brain and spinal cord, caused by eastern equine encephalomyelitis (EEE) virus, western equine encephalomyelitis (WEE) virus, or Venezuelan equine encephalomyelitis (vee) virus
Estrogens	General term for female sex hormones
Estrus	"Heat"; a recurrent period of varying length, during which the mare produces a watery secretion from the genital tract, becomes sexually receptive to the stallion, and ovulates
Etiology	The cause of a disease
Extension	Extension the movement of a horse's leg forward due to the use of extensor tendons. The extension of the paces is the lengthening of the frame and stride. The opposite of collection.
Field of vision	Entire spatial area from which the complete visual image of an eye is formed
Five-Gaited	Horses shown at the walk, trot and canter, as well as the "slow gait" and the "rack" is called five gaited.
Flehmen Reaction	A unique behavior wherein the horse extends its head and curls back the upper lip while drawing air into the nasal cavity; usually expressed by a stallion attempting to detect estrus ("heat") in a mare.
Flight Distance	The social (reactive) distance at which an animal will start to flee from an approaching intruder. Taming the animal reduces the flight distance to 0.
Foal Heat	A mare's first heat period after the birth of a foal.
Follicle-Stimulating Hormone (FSH)	Hormone produced by the pituitary gland that stimulates the development of ovarian follicles in the female and sperm production in the male.
Fox Trot	A slow, short, broken, nodding trot.  The hind leg of one side strikes only an instant before the diagonal fore leg.
Gait	The paces at which horses move, usually the walk, trot, canter and gallop.
Gaited Horse	Horses which move at paces other than the walk, trot and canter - such as the Saddlebred, the Paso Fino and the Icelandic.
Gallop (Or Run)	A fast, four-beat gait.  Sequence: 1. One hind foot strikes the ground 2. The other hind foot strikes the ground 3. The diagonal front foot strikes the ground 4. The remaining front foot strikes the ground
Galvaynes Groove	Dark line which appears on the upper corner incisor of horses between 8 and 10 years of age. Since it extends downward gradually, it can be used to estimate the age of a horse.
Gas Colic	Colic caused by over consumption of lush grass feed, resulting in excessive gas production in the intestine.
Gastric	Pertaining to the stomach.
Gastritis	Inflammation of the stomach.
Gestation	The full period of pregnancy, from fertilization of the egg by a spermatozoon until birth.
Gonadotropin-Releasing Hormone (GnRH)	Hormone released from the hypothalamus of the brain that triggers the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary gland.
Hormone	Any molecule produced by an organ or tissue, usually in extremely small quantities, that has a specific regulatory effect on the activity of another organ or tissue.
Host	The living organism in or on which a parasite resides.
Human Chorionic Gonadotropin (HCG)	Hormone produced by the placenta that can stimulate ovulation.
Hypothalamus	The part of the brain concerned with operation of much of the autonomic (unconscious) nervous system, the production of specific hormones that are subsequently stored in and released by the pituitary gland, and the regulation of body temperature, sleep cycles, and food and water intake.
Immunization	The administration of a vaccine in order to produce protective immunity against the infectious disease agent(s) present in the vaccine.
Impaction Colic	Colic resulting in blockage of the intestine; can result from excessive consumption of grain or lush pasture, or ingestion of foreign material.
Inactivated ("Killed") Vaccine	A vaccine in which the infectious agent has been modified in some way (most often chemically) so that it no longer can infect and replicate within the host, but nevertheless is still capable of stimulating an immune response.
Incisors	The front teeth.
Infective Stage	The specific stage in the life cycle of a parasite that is able to initiate an infection in a definitive or intermediate host.
Infertility	Diminished ability to produce offspring.
Inflammation	Protective response, often localized, involving white blood cells and other components of the body, wherein a disease agent or other irritant factor is sequestered and attempts made to destroy it or neutralize its effects.
Influenza	Acute viral infection involving the respiratory tract, occurring in isolated cases or epidemics, striking many continents simultaneously or in sequence. It is marked by inflammation of the nasal mucosa, the pharynx, the conjunctiva, the lungs and sometimes the heart muscle.
Intermediate Host	A host that (usually) is essential to the life cycle of a parasite and in which the parasite undergoes development to juvenile but not mature stages.
Ivermectin	Generic name for an anti-parasite agent.
Jog	The western pleasure form of a trot though it is considerably slower. Sequence: The fore foot of one side and the hind foot of the other side strike the ground together
Large Strongyles	Intestinal parasites also known as bloodworms.
Larva	Insect or worm in an immature stage of development.
Larvacide	Agent used to kill pests in their immature stage of development.
Lateral Gait	Both off limbs move more or less in unison, as do both near limbs. A pace is a good example of a lateral gait.
Lead	Term used to indicate the horse's leading leg in canter i.e. "right lead canter" or "left lead canter".
Linear hierarchy	Specific social order from number one, alpha, individual on down. Arrangement of dominance within a group. Linear-tending groups share some positions.
Lockjaw	Synonym for trismus, a clinical sign of tetanus.
Lope	A canter that is performed as slowly as possible for western events such as western pleasure.  Sequence:  1. One hind foot strikes the ground 2. The other hind foot and diagonal front foot strike the ground together 3. The remaining front foot strikes the ground
Monocular fixation	Focusing of one eye on an object.
Navicular Bone	Small bone within the hoof, fitting horizontally between the second phalanx, or short pastern and the coffin bone.
Navicular Disease	Degeneration of the navicular bone, usually on the back surface where the deep flexor tendon passes over the bone. Causes pain and lameness
Neurectomy	Cutting of nerves supplying sensation to the foot. Also known as de-nerving. Used as a treatment in cases of navicular disease.
Overreaching	Where the toe of the hind foot catches and injures the back of the pastern or heel of the front foot. Occurs when the horse is galloping or jumping.
Oviducts	Uterine or fallopian tubes.
Ovulation	Release of an egg from an ovary.
Oxytocin	A hormone formed in the hypothalamic region of the brain and stored in the pituitary gland; it stimulates contraction of the uterus and milk ejection from the mammary glands.
Pace	A fast, two-beat gait.   Sequence: 1. The front and hind feet on the same side strike the ground together.   2. All four feet are off the ground for a moment.
Palmar Digital Neurectomy	Permanent nerve block performed to relieve navicular disease.
Parasite	Any organism that is dependent in some manner for its continued existence on another organism (its host), most often to the detriment of the host.
Parturition	The act of giving birth.
Pecking Order	Refers to the social order of individuals.
Peritonitis	Inflammation of the membrane lining the abdominal walls and covering the abdominal organs.
Pheromone	A specific chemical secreted as a means of communication among individuals of a species. Signaling pheromones trigger a specific behavior.
Pinworm	Roundworm parasite residing in the horse’s rectum, causing severe itching and tail rubbing.
Polyestrous	Having more than a single estrous cycle per year.
Postpartum	Occurring after birth.
Potomac Horse Fever	A gastrointestinal disease of horses, characterized by high fever, colitis (inflammation of the large intestine), diarrhea, and dehydration; caused by a rickettsia, Ehrlichia risticii
Progesterone	Hormone secreted by the corpus luteum, adrenal cortex, and placenta, whose primary function is to prepare the uterus for pregnancy; also called progestin.
Rabies	Inevitably fatal viral disease, primarily of bats and carnivores, characterized by neurological dysfunction; caused by a rhabdovirus.
Rack	A fast, flashy, evenly-timed four-beat gait.  The feet start and stop at the same intervals.  It has extreme knee action and considerable speed, with the front legs appearing to trot while the hind legs seem to be pacing. The fifth gait of the American Saddlebred
Recumbency	Inability to stand.
Recumbent	Lying down.
Rhinopneumontis	Respiratory condition of horses caused by equine herpes virus.
Rickettsiae (Singular Rickettsia)	Specialized bacteria that multiply only within host cells and that are usually transmitted to animals or human beings by lice, ticks, fleas, or mites; examples include Ehrlichia risticii, the cause of Potomac horse fever (equine monocytic ehrlichiosis), and Ehrlichia equi, the cause of equine granulocytic ehrlichiosis.
Root	The portion of a tooth that lies below the gum line.
Roundworm	Common name for ascarids, an internal equine parasite.
Sleeping Sickness	Common term for the depression and somnolence characteristic of equine viral encephalomyelitis.
Small Strongyles	Any of 50 species of Strongyles one centimeter or less in length at maturity that commonly infect the intestines of the horse.
Stepping Pace	A slow, lateral, four-beat gait.  Each foot strikes the ground at a different time from the others.  Sequence: 1. The hind foot strikes the ground 2. The fore foot on the same side strikes the ground 3. The other hind foot strikes the ground 4. The remaining fore foot strikes the ground
Stereotyped Behaviors	An intentional, repetitive behavior that is nonfunctional. Many are performed in a rhythmic manner. Usually develop in an effort to cope with environmental stress such as isolation, little exercise, etc.