EQ GLOSSARY

adrenocorticotropic hormone (ACTH)---a hormone released by the pituitary gland that regulates the release of cortisol by the adrenal glands. Banamine--- trade name of flunixin meglumine, a nonsteroidal anti-inflammatory drug used to control inflammation and pain primarily associated with colic and muscle injuries. bute--- colloquial term for phenylbutazone, an odorless anti-inflammatory medication used in the management of joint, bone and muscle injuries or disorders. dexamethasone suppression test--- screening test that suppresses the levels of adrenocorticotropic hormone (ACTH) released from the pituitary, to assess the response of the adrenal glands; used to diagnose pituitary pars intermedia dysfunction, also known as Cushing’s disease. eastern equine encephalomyelitis (EEE, encephalomyelitis)---brain and spinal-cord inflammation in horses, caused by a specific viral strain transmitted by mosquitoes. EEE is characterized by fever and/or stupor and is almost always fatal. 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 EHV-1 and -4 can cause neurological signs, including progressive weakness and in- coordination. EHV-3 causes a venereal disease called equine coital exanthema. hydrocephalus--- abnormal amount of fluid beneath the skull, resulting in an enlarged head, brain atrophy and mental deterioration. inbreeding--- breeding two very closely related individuals, such as son and mother or siblings. influenza--- acute viral infection involving the respiratory tract. Influenza is marked by inflammation of the nasal mucosa, the pharynx, the conjunctiva, the lungs and sometimes the heart muscle. 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. line breeding--- breeding two related individuals, usually at least two to three generations removed, to intensify the inheritance from a particular ancestor. nasogastric tube--- flexible tube inserted into the nostrils and passed into the stomach to introduce or drain fluid (reflux). phenotype--- physical makeup and appearance of an organism as determined by its genes and environment; expression of a genotype. progesterone--- female hormone secreted by the corpus luteum of the ovary and, in pregnancy, by the placenta; promotes implantation of the fertilized egg and helps maintain pregnancy by preventing the estrous cycle. tail-female line--- continuous matriarchal ancestry. tetanus--- rigid paralytic disease caused by Clostridium tetani, an anaerobic bacterium that lives in soil and feces. thyrotropin-releasing hormone stimulation test--- screening test that measures levels of adrenocorticotropic hormone (ACTH) in a horse’s blood before and after the administration of synthetic thyrotropin-releasing hormone (TRH); used to diagnose pituitary pars intermedia dysfunction, also known as Cushing’s disease. West Nile virus--- flavivirus transmitted by mosquitoes. West Nile virus can infect birds, horses, humans and other mammals. In horses, as in people, infection with the virus usually causes little or no illness. For reasons not yet determined, however, West Nile infection sometimes triggers swelling of the brain (encephalitis) that produces limb weakness, muscle fasciculation (twitching), incoordination, behavioral changes, paralysis and recumbency. In severe cases, West Nile encephalitis can lead to coma and death. western equine encephalomyelitis (WEE)--brain and spinal-cord inflammation in horses, caused by a specific viral strain transmitted by mosquitoes. Signs include fever, depression, ataxia and head pressing. wobbles (cervical stenotic myelopathy)--incoordination due to malformation of the vertebrae in the neck that causes compression or “pinching” of the spinal cord. In dynamic compression, the vertebrae allow too much motion in the joints, which pinches the cord. In static compression, excess growth of bone and/or cartilage narrows the spinal canal and impinges on the cord.