In older adults, mild thickening, calcification, or both of a trileaflet aortic valve without restricted leaflet motion (i.e., aortic sclerosis) affects about 25% of the population older than 65 years. Calcific aortic stenosis (Fig. 1) , however, affects approximately 2% to 3% of those older than 75 years.alcific aortic stenosis, formerly referred to as degenerative, affects trileaflet aortic valves, often in patients with other risk factors for atherosclerotic disease. The aortic valve leaflets undergo an active disease process, with lipid deposition, inflammation, and osteo-calcific changes.
The three most common toxic weeds to horses that may be contained in hay are: Hoary alyssum, wild parsnip and poison hemlock. 1  Hoary alyssum - Hoary alyssum is a perennial weed. 2  Wild parsnip - Wild parsnip is mainly found in ditches and fields and is a biennial and is poisonous to horses. 3  Poison hemlock - Poison hemlock is poisonous to horses.
Horse owners must be knowledgeable and aware of the diseases that are common to horses and other livestock species and to humans. A severe outbreak of any of these diseases would have a substantial veterinary and economic impact on the U.S., and on the horse industry.orse owners must be knowledgeable and aware of the diseases that are common to horses and other livestock species and to humans. A severe outbreak of any of these diseases would have a substantial veterinary and economic impact on the U.S., and on the horse industry.