Spontaneous and experimental variations in body weight, food intake and metabolic rate in captive dormice (Glis glis).

Captive dormice (Glis glis) showed spontaneous cyclical fluctuations in body weight that were not synchronous between animals and not directly related to season. Presenting the animals with a varied and palatable (cafeteria) diet for short periods caused marked increases in energy intake and body weight, and higher levels of oxygen consumption (V02). The level of hyperphagia was fairly constant, but the rise in V02 during cafeteria feeding varied (20-80%) according to season, being greatest in the winter (Nov.-Jan.). Removal of the cafeteria foods caused weight loss, hypophagia and a fall in V02 to levels below that seen in either normally-fed or fasted dormice. This hypometabolism was associated with increased periods of sleep and torpor, and it is suggested that the excess fat deposition resulting from cafeteria feeding may have induced a transient "hibernation-like" state.