Effect of Choline on the Methionine Requirements of Broiler Chickens

BOTH methionine and choline are known to furnish labile methyl groups as well as assume independent essential roles in nutrition. The work of Klose and Almquist (1941), Gillis and Norris (1951), Jukes and Stockstad (1952), Stekol et al. (1953) and others has established the common role of these compounds as methyl donors Young, Norris and Heuser (1954), using vitamin B12 depleted chicks and a basal diet deficient in choline, methionine and vitamin B12, found supplementation with mono-methylaminoethanol, homocystine, and betaine, both in the presence and absence of vitamin B12, to be utilized as effectively as equimolar concentrations of dietary choline and methionine. In the absence of sufficient betaine to methylate adequately the precursors of choline or methionine, vitamin B12 improved the growth rate indicating that it is required in the synthesis of methyl groups in chicks, but not for transmethylation reactions. Choline is also known to be associated with fat…