RESUMEN
As in humans, an increase in the incidence of concurrent diseases occurs in dogs and cats with age. To some extent considerable species specific differences occur; the dog is affected more than the cat. In advanced age more chronic diseases are observed as in humans. The following diseases show a particular predisposition in aged dogs and cats: The dog exhibits especially non-inflammatory skin diseases, cardiopathies, chronic diseases of the respiratory tract, oral cavity, liver, kidneys and urinary tract, diseases of the CNS, and tumours, whereas the cat suffers from the leukaemia complex, to a lesser extent from non-inflammatory skin and cardiac diseases, also from chronic diseases of the oral cavity, gastrointestinal tract, liver, kidneys and urinary tract, endocrine system, and tumours.
