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In the broadest sense, aging refers to the natural, progressive series of life stages beginning with conception and continuing through development, maturation, and senescence. Most often, however, the term is more narrowly used to refer to the complex set of biological changes occurring in older individuals that result in a progressive reduction of the ability to maintain homeostasis when exposed to internal physiologic and external environmental stresses.
Older dogs make up a substantial proportion of the pet dog population in the United States. One
Dr. Daristotle's present address is 4272 State Rte 732 W, Eaton, OH 45320.