Excretion of Formiminoglutamic Acid as an Index of Vitamin B 12,Folic Acid,and Methionine Deficiencies. ∗ ‡

Abstract

Summary

Day old chicks were fed a diet borderline in methionine for 3 to 4 weeks. They excreted large amounts of formiminoglutamic acid (FGA). a metabolite of histidine, when either folic acid or Vit. B₁₂ was omitted from the diet. FGA was excreted in very small amounts by control chicks fed the complete diet. Incorporation of supplemental methionine at 1% of the diet caused a marked reduction in FGA excretion of Vit. B₁₂ deficient chicks and a moderate reduction in the folic acid deficient chicks. Further elevation of dietary histidine and continuation of the supplemental methionine resulted in increased FGA excretion which was relatively greater in the folic acid deficient than in the Vit. B₁₂ deficient group. Only on the last day of the experiment was the excretion elevated for the control group. Chicks fed diets severely deficient in methionine did not excrete large amounts of FGA until Vit. B₁₂ was omitted.