AVS-3700 Lecture Notes - Lecture 17: Cystine, Methionine, Lysine
Document Summary
Total amino acids are determined through chemical analysis. Digestible amino acids = metabolizable = what the bird absorbs. Most costly nutrients in the broiler diet: energy, amino acids, phosphorous. Nutrients drive the cost of broiler production. Choline is required in large amounts in the diets of broilers. Vitamins and minerals are usually fed as a premix. Crude protein = nitrogen content * 6. 25. Methionine and cystine are sulfur amino acids: feathers are high in cystine, methionine can convert cystine. Limiting amino acids: cystine, lysine, threonine. It is illegal to put hormones in chicken feed. Energy requirements increase with the age/weight of the bird: the requirements never plateau because the birds do not live long enough. Mineral and vitamin requirements decrease with age because the birds eat more and don"t grow as fast. Wheat is lower in energy and higher in protein than corn. Causes yellow pigmentation in meat and egg yolks.