Lysine and arginine requirements of broiler chickens at two- to three-week intervals to eight weeks of age. Poult. Sci

Abstract

ABSTRACT Four experiments were conducted to de-termine the arginine and lysine requirements of male chickens for 2- to 3-wk intervals from the time of hatching until 8 wk of age. Weight gain, breast muscle growth, and feed efficiency were used as response for each interval. Dietary requirements for lysine and arginine were esti-mated by broken-line regression analysis of responses to six or seven dietary levels of each amino acid. Dietary crude protein levels were 22, 21, 20, and 18 % in four consecutive experiments from 0 to 2, 2 to 4, 3 to 6, and 5 to 8 wk of age. An occasional estimate of requirement was not determined (ND) because the response did not conform to the regression model. The values for lysine and arginine requirements determined from breast mus-cle gain (weight gain of pectoralis major plus pectorali