Immunity and metabolic rate: the course of notoedric scabies in rats with different metabolic rates

Abstract

1. Two experiments are described investigating the effects of level of metabolism on (a) resistance to, and (b) recovery from, Notoedric scabies of rats. The progress and severity of the disease was measured by weekly counts of the number of lesions; the metabolic rate in some rats was raised by administration of iodinated casein and in others was depressed by methyl thiouracil.2. In normal rats, the initial severe phase of the disease was followed by a partial recovery with survival of a smaller population of parasites.3. This recovery process in established infestations was hastened by elevation and retarded by depression of the metabolic rate.4. Resistance to the development of severe disease was enhanced by elevation and reduced by depression of the basal metabolic rate.5. The level of the residual infestation, after the severe phase of the disease had passed, was also affected by the treatment, being decreased by the higher but increased by the lower metabolic rate.