Evaluation of Dietary Methionine, Folic Acid and Cyanocobalamin (B₁₂) and Their Interactions in Laying Hen Performance

O.M. El - Husseiny, A.Z. Soliman, I.I. Omara and H.M.R. El - Sherif

International Journal of Poultry Science 7 ( 5 ): 461 - 469 , 2008