The Influence of Relative Humidity upon Vitamin Deficiencies in Rats

Abstract

The growth of weanling rats fed a complete diet or diets deficient in vitamin A, riboflavin, or pantothenic acid was not found to be affected by extremely low or high humidity conditions; however, animals which were deficient in pyrdioxine grew more rapidly when maintained at a relative humidity of 90%. The water consumption of rats receiving the complete diet and diets deficient in pyridoxine and pantothenic acid was greatest at low relative humidity. At 5 to 10% relative humidity, a scaly dermatosis occurred within 12 days upon the paws of rats fed the complete diet as well as those fed diets deficient in vitamin A, riboflavin, pyridoxine or pantothenic acid. The animals fed the complete diet spontaneously recovered from their dermatosis, while those rats which remained vitamin-deficient did not recover. The addition of iodinated casein to the complete diet decreased the extent of dermatosis. At 30% relative humidity, dermatosis occurred only on the paws of the vitamin-deficient animals. At and above a relative humidity of 50%, dermatosis was not observed on the paws of the vitamin-deficient rats. At 90% relative humidity a red pigment was observed to occur extensively on the fur of the heads of animals fed diets deficient in pyridoxine, riboflavin and pantothenic acid. This condition did not exist at 50% relative humidity or below.