GLOSSARY

WORDS FOLLOWED BY THIS SYMBOL ARE DEFINED HERE

anaphylactic shock (anaphylaxis)---acute, massive, often fatal allergic reaction triggered by the introduction of an antigen into a horse who already has become hypersensitized to that antigen. antibody--- disease-fighting substance produced by the body in response to the presence of an antigen. arthroscopy--- examination of the interior of a joint through a slender fiber-optic instrument; used primarily in joint surgery, arthroscopy has rendered many more invasive techniques obsolete. ataxia--- incoordination of the muscles, which results in shaky, irregular movements; may also be accompanied by weakness and loss of proprioception. choke--- in horses, obstruction of the esophagus; in people, obstruction of the windpipe (trachea). deep digital flexor tendon--- tendon connecting the deep muscles at the back of the forearm and gaskin to the coffin bone in the foot. equine herpes myeloencephalopathy--neurological disorder caused when equine herpesvirus-1 or -4 infects the brain and spinal cord. equine herpesvirus (EHV)---a family of viruses that primarily cause chronic respiratory infections in horses (EHV-1, EHV-4). EHV-1 can also cause abortions in mares and, in rare cases, both EHV1 and -4 can cause neurological signs, including progressive weakness and incoordination. EHV-3 causes a venereal disease called equine coital exanthema. fecal egg count--- laboratory procedure for determining the number of internal-parasite eggs in a fecal sample; used primarily to estimate a horse’s level of infection with ascarids and/or strongyles. heaves--- common term for recurrent airway obstruction, a respiratory disease, usually of older horses, induced by exposure to dusts typically found in stables and resulting in narrowing of the small airways of the lungs. hives (urticaria)---soft, raised bumps, one-third to more than an inch in diameter, which break out simultaneously in groups in response to an allergic reaction. ingesta--- the partially digested contents of the intestinal tract; the foodstuff eaten. laminitis--- inflammation of the sensitive plates of soft tissue (laminae) within the horse’s foot caused by physical or physiologic injury. Severe cases of laminitis may result in founder, an internal deformity of the foot. Acute laminitis sets in rapidly and usually responds to appropriate, intensive treatment, while chronic laminitis is a persistent, long-term condition that may be unresponsive to treatment. necropsy--- examination of an animal’s body after death, normally done to ascertain the cause of death. pH--- measure expressing the acidic or basic nature of a substance, on a scale of 0 (most acidic) to 14 (most basic). plasma--- blood liquid that contains specialized cells, such as platelets, and the proteins related to clotting; obtained by centrifuging whole unclotted blood to settle out the other cells. platelet-rich plasma (PRP)---derived from a patient’s own blood, PRP is plasma that has undergone processing to concentrate platelets. PRP may be injected into soft tissue injuries so that the multiple growth factors that platelets release will enhance healing. platelets--- disk-shaped cell fragments responsible for coagulation of the blood. radius--- principal bone of the forearm. rhinopneumonitis--- highly contagious disease caused by herpesviruses (EHV-1, EHV4); characterized by fever, mild respiratory infection and, in mares, abortion. In rare cases, some strains of these herpesviruses also cause potentially fatal neurological complications. suspensory ligament--- strip of fibrous tissue running from the back of the upper cannon bone over the fetlock joint to the pastern bones. Provides major support for the fetlock joint, preventing it from sinking to the ground. sweet itch--- allergy to the saliva of one or more various insects (culicoides, gnats, midges, no-seeums); produces an inflammatory, itchy thickening and scabbing of the skin of the rump and/or withers, which become bare and weepy when the horse scratches. synapse--- junction point on a neuron at which impulses are transmitted to other neurons, muscle cells or glands. toxin--- poisonous substance produced by a living organism. uveitis--- inflammation of the pigmented structures within the eyeball.