Dysosmia caused by encephalitis in a dog.

A 1- to 2-year-old Beagle was referred for evaluation of a disorder of the sense of smell. The dog had suddenly lost the ability to find rabbits, even though it previously had won field trials. Clinical findings indicated mild encephalitis with some capability to respond to odoriferous stimuli. An unusual test of the sense of smell is described; results indicated some sense of smell, although behavioral response to the odor was inappropriate. It was suspected that canine distemper encephalitis may have been associated with the dysosmia.