Ascorbic Acid Requirement of the Guinea Pig Using Growth and Tissue Ascorbic Acid Concentrations as Criteria

The ascorbic acid requirement of guinea pigs fed a purified diet was determined using growth as the criterion. Depleted and non-depleted animals were used. Graded levels up to the 0.5 mg per 100 gm body weight level gave significant differences in growth during a 42-day period. The ascorbic acid requirement, according to out investigation, is 0.5 mg per 100 gm of body weight per day for both young and young adult animals. Ascorbic acid was determined in spleen, liver, adrenals and blood 20 to 24 hours after supplementation. Significant differences were observed in the tissue ascorbic acid concentration up to the 0.5 mg level of supplementation which gave maximum growth; no significant difference was observed between the 0.5 and 0.7 mg levels. This, too, tends to indicate a requirement of 0.5 mg per 100 gm of body weight. In blood, no significant differences among levels were observed.