Action of Vitamin B 12 in Counteracting Glycine Toxicity in the Chick. ∗

Abstract

Summary

Vitamin B₁₂-deficient chicks were fed vitamin B₁₂-deficient basal diets supplemented with 0, 1 and 4% glycine in combination with 0, 3, and 30 μg of vitamin B₁₂ (supplied by Merck's APF Supplement No. 3) per kilogram. The growth of the chicks that received either 1 or 4% added glycine in the vitamin B₁₂-deficient basal diets was depressed. Those chicks which received 4% added glycine without vitamin B₁₂ suffered excessive mortality. The addition of as little as 3 micrograms of vitamin B₁₂ per kilo of diet overcame the inhibitory action of both levels of glycine. These results indicate that vitamin B₁₂ functions in the metabolism of glycine.