Even a small shortage of arginine or methionine costs performance
540 broilers were fed 90%, 100% or 110% of NRC arginine and methionine for 42 days. Correcting the 90% deficiency increased weight gain and improved feed conversion. Arginine also increased spleen and bursa weight and antibody responses to bronchitis and Gumboro, and methionine improved the Gumboro response.