The basal metabolism in vitamin B deficiency.

Abstract

The heat production in dogs during rest has been determined with the respiration calorimeter when these animals were fed with diets deficient in vitamin B. The purified food mixture fed to Dogs XXIV and XXV was complete in all respects with the exception of vitamins B and C. It was composed of casein, butter fat, lard, sucrose, salt mixture, and bone ash. Vitamin C was omitted since it has been shown that dogs, when fed with such mixtures containing vitamin B, remain in normal condition over long periods of time and show no effects from this lack. 1 Basal metabolism measurements were made by the usual technique employed in this laboratory.

On Dog XXIV the metabolism was determined at approximately weekly intervals during the course of the ingestion of the standard vitamin B-free diet. In this animal the basal heat production gradually fell, but the diminution was no greater than that which would be expected from the decreased body weight of the animal due to a decreasing food intake. On the day before the development of polyneuritic symptoms and on the four days following the removal of these symptoms by the administration of 20 gm. of yeast vitamin (Harris), the basal metabolism was remarkably constant, thus indicating that vitamin B deficiency per se does not influence heat production.

In the case of Dog XXV the basal metabolism was determined at the height of polyneuritis and was found to be about 25 per cent higher than the normal value to which it gradually fell after the removal of the symptoms. In this case the high heat production must have been due to the extreme muscular tonicity caused by the polyneuritic condition and only indirectly to the vitamin B deficiency.