GLOSSARY

Words followed by this symbol 0 are defined here

anaplasmosis (formerly equine granulocytic ehrlichiosis)---disease caused by the bacterium Anaplasma phagocytophilum, which is transmitted by ticks. Most cases occur in northern California, but the disease has been seen all over the country. Signs include fever, lethargy, poor appetite and swelling of the limbs. bar shoe--- horseshoe with no opening between the heels; forms a continuous circle; used to extend the base of support to the rear of the heels. colitis--- inflammation of the colon. corticosteroids--- analogs of the hormone cortisol produced primarily by the adrenal glands; they may be natural or synthetically produced for injection. dopamine--- one of the neurotransmitters, chemical “messengers” that aid in transmitting nerve impulses across synapses between nerve cells. equine 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. 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. 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. limbic system (limbic ring)---group of subcortical brain structures (hypothalamus, hippocampus and amygdala) of the center of the brain that are concerned with emotion, motivation and some internal organ functions. lipoma--- benign tumor of fat tissue. lymph--- transparent, nutritive yellow liquid that exudes from blood vessels into tissue spaces and is drained back into the veins through lymph vessels. Lymph plays an important role in fighting infection and maintaining the body’s fluid balance. lymph nodes--- cellular filters along the lymph vessels which collect fluids from between the cells and return them to the circulation. neurotransmitters--- chemical messengers in the nervous system that convey electrical impulses across the space between cells. nonsteroidal anti-inflammatory drug (NSAID)---drug that contains no steroids and acts to reduce heat and swelling. polysaccharide storage myopathy (PSSM, equine polysaccharide storage myopathy, EPSM)---disease that causes abnormal accumulation of sugars (glycogen and polysaccharide) in the muscle cells. Signs, which are consistent with “tying up,” include contracted, painful muscles over the lumbar spine and hindquarters, especially during or after exercise. Other signs include excessive sweating, rapid breathing and heart rate, muscle tremors, and dark urine. Two forms have been identified: PSSM Type 1 results from a gene mutation; the cause of PSSM Type 2 is unknown. Potomac horse fever (monocytic ehrlichiosis) ---disease caused by a rickettsial organism, Neorickettsia risticii. Named after the Potomac River Valley where it was first recognized in 1979, the disease is characterized by fever, diarrhea and laminitis. purpura hemorrhagica--- acute, noncontagious disease of horses and people, characterized by edema, muscle soreness and inflammation of mucous membranes; thought to be an allergichypersensitivity reaction to bacterial antigens circulating in the bloodstream. strangles (distemper)---highly contagious infection of the lymph nodes, usually of the head, caused by Streptococcus equi bacteria. The abscesses may become so large as to obstruct the airway (hence the term “strangles”) and may break internally, draining a thick, yellow pus through the nose, or externally, draining through a spontaneous or surgical opening in the skin. synapse--- junction point on a neuron at which impulses are transmitted to other neurons, muscle cells or glands. white cells (leukocytes, white blood cells)--colorless blood cells active in the body’s defense against infection or other assault. There are five types: neutrophils, lymphocytes, eosinophils, monocytes and basophils.