RESTING METABOLISM DURING THE STABLE PHASE OF FEVER IN RATS

1. The effect of a drop in ambient temperature (T(a)) on deep body tem perature (T(b)) of normal rats and rats in the stable second phase of fever were investigated. 2. The resting metabolisms of normal rats and of rats in the stable second phase of fever were measured. 3. A 20-de grees-C drop in T(a) gave an average rise in T(b) of normal rats of 0. 3-degrees-C. The same treatment did not result in a significant change in the T(b) of the febrile rats. 4. The metabolism of the rats in the stable second phase of fever was significantly higher than that of th e normal rats at all temperatures. 5. The energy expenditure during th e stable second phase of fever was higher than could be caused by norm al Q(10)-effects of the increased deep body temperature. This indicate s an increased heat loss in the febrile animals, which was balancing o ut the increase in heat production.