GLOSSARY

antigen-antibody reaction--- interaction between a foreign substance (antigen) and the body’s defensive proteins (antibodies). Bend Or spots--- random patches of darker color that appear on the coats of some horses; named for the British-born Thoroughbred stallion Bend Or (1877) who had multiple spots, as did many of his progeny. Birdcatcher spots--- round white spots, generally an inch or less in diameter, that may appear randomly on a dark coat. Named for the Irishborn Thoroughbred stallion Birdcatcher (1833), the spots may not appear until the horse is mature, and they may vanish over time. cartilage--- specialized type of fibrous connective tissue covering bone ends at joints; also structural basis for the ears and nostrils. dimethylsulfoxide (DMSO)---organic chemical that has a number of medicinal properties, including anti-inflammatory, antibacterial and analgesic; DMSO can pass readily through the skin. DNA (deoxyribonucleic acid)---large organic molecule that consists of two chains of nucleotides wound around each other; the material of which genes are made. Genes are responsible for the individual inherited characteristics of living organisms. endoscope--- small, flexible tube equipped with light and a viewing device; used to examine or operate on body passages or internal organs. enzyme--- any of the numerous facilitator proteins enabling the building up, altering or breaking down of other specific substances with which they interact. eosinophil--- type of white cell that increases in number during certain chronic infections, allergies and parasitic infestations. equine metabolic syndrome--- endocrine disorder characterized by increased fat deposits in specific locations of the body or overall obesity; insulin resistance, which leads to abnormally high levels of the hormone circulating in the blood stream; and a predisposition toward laminitis in the absence of other recognized causes. fructan--- naturally occurring sugar that is a source of stored energy for plants. Fructan, along with glucose, fructose, sucrose and starch, is a nonstructural carbohydrate found in grasses and feeds. insulin--- hormone secreted by the pancreas to control blood sugar level and utilization of sugar in the body. insulin resistance--- metabolic disorder, similar to type-2 diabetes, that occurs when certain cells in the body become less sensitive to the action of insulin, and normal amounts of the hormone can no longer keep adequate amounts of glucose moving into the cells for use as fuel. 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. mediators--- biochemicals released when injured tissue stimulates the inflammatory process. Actions caused or aided by different mediators produce swelling, heat, pain and, ultimately, healing. MSM (methylsulfonylmethane)---sulfurcontaining oral preparation that is a chemical fraction of dimethylsulfoxide (DMSO), an organic substance with anti-inflammatory, antibacterial and analgesic properties; popular in the management of athletic pain. nonsteroidal anti-inflammatory drug (NSAID)---drug that contains no steroids and acts to reduce heat and swelling. oligofructose--- a type of naturally occurring sugar derived from plants. Overdoses of oligofructose are used to induce laminitis in horses for use in research. pituitary pars intermedia dysfunction (PPID, Cushing’s disease)---disease caused when the cortex of the adrenal gland produces excessive amounts of hormones, including cortisol; signs include persistent long hair, thin skin, fragile bones, stupor, weakness and sweating. sesamoid bones (proximal sesamoids)--pyramid-shaped bones that form the back of the fetlock joint and serve to improve supporting leverage of flexor tendons that pass behind them; part of the suspensory apparatus. tail female line--- continuous matriarchal ancestry. titer--- measurement of the concentration of an antibody in blood serum or other solution. “High titer” refers to blood serum containing high antibody levels.