Metabolism and Nutrition: Amino Acids

In the United States, guinea fowl (GF) production has continued to increase due to increased demand and consumption of specialty meats . However, there is lack of information on optimum nutrients, such as amino acids, that would support optimum growth performance and minimize production cost of the GF . The amino acid methionine is most limiting in poultry feeding while methionine and cysteine are essential sulfur-containing amino acids that are required for growth and key metabolic processes . The objective of this study was to determine methionine and cysteine requirements for optimum growth performance of the French GF broiler . To meet this objective, experimental birds were fed corn-soy based diets containing 0 .50, 0 .45 and 0 .40% methionine each in combination with 0 .35, 0 .40 and 0 .45% cysteine, respectively from hatch to 4 weeks of age (WOA) . The birds were reared using standard commercial rearing techniques . Feed and water was provided at free choice and optimal levels of methionine and cysteine were determined through measurements of weekly body weight gain (BWG), feed consumption, and feed conversion ratio . Birds fed diets containing 0 .50% methionine in combination with 0 .35% cysteine exhibited higher BWG and overall performance when compared with other dietary treatments (P < 0 .05) . Dietary cysteine levels above 0 .35% and methionine levels below 0 .50% depressed growth and overall bird performance, and increased mortality . Therefore, at hatch to 4 WOA, French GF broilers would utilize more efficiently diets containing 0.50% methionine and 0 .35% cysteine .