Niacin Deficiency in Rabbits and Response to Tryptophane and to Niacin

Abstract

Summary

In the study reported above, it is shown that the exclusion of niacin from the ration of rabbits for 8 weeks was accompanied by a reduction of hemoglobin and the cellular components of the blood. After 12 weeks on this ration, there was a reduction of niacin concentration in the livers and the hamstring muscles.

After the animals had been on the niacin-deficient. ration for 8 weeks, attempts to cure the deficiency by feeding tryptophane or, and niacin for 4 weeks were made. The addition of 400 mg dl-tryptophane per rabbit or 10 mg niacin per kg body weight to the daily ration of the animals was followed by increases in appetites. The responses in weight gain, hemoglobin, red and white blood cells were about equal when either of the substances were fed. The addition of both compounds to the ration resulted in greater responses. The niacin content of the livers of the rabbits that received either tryptophane or niacin supplements was approximately normal. The niacin in the muscles of the rabbits that were supplemented with niacin wras found to be high, while the tryptophane animals had a niacin level similar to the concentration found in the muscles of the deficient rabbits.