The amino acid requirements of the growing chick

Abstract

The amino acid requirements for the growing chick determined by Hewitt and Lewis (1972a) were tested at different protein levels. Satisfactory growth was obtained with 22 to 24% protein in the diet dry matter. Nitrogen balance data indicated that a good balance between amino acids, with no deficiencies, had been achieved. The results of Hewitt and Lewis (1972a) were evaluated in conjunction with other published reports and a new set of requirement values derived. These were tested in a second experiment at different protein and energy levels. Excellent growth was recorded to 3 weeks of age when the diet satisfied these values and contained 0.9% lysine and 21% protein with a metabolisable energy value of 3.25 kcal/g.