Increasing amino acid density improves growth performance and processing yield in Cobb 700 × MV broilers

Abstract

Summary The objective of this study was to evaluate the effect of digestible essential AA density (dEAA) on the performance and processing yield of straight-run Cobb 700 × MV broilers. Broilers were fed a control diet based on the breeder's nutrient recommendations or one of 4 treatments consisting of 5% incremental increases in dEAA density over the control (+5, +10, +15, and +20% dEAA). The digestible lysine content of the control diets was 1.18, 1.07, 0.96, and 0.89% during the starter (0–12 D), grower (12–26 D), finisher (26–36 D), and withdrawal (36–49 D) diets, respectively. Broilers fed the increased dEAA were heavier at 12, 26, and 36 D as compared with those fed the control, and cumulative feed conversion ratio (0–49 D) was decreased by 6 and 8 points when dEAA was increased over the control diet by +10 and +15%, respectively. A 5.75% increase in boneless–skinless breast yield as compared with the control diet was observed when broilers were fed the +20% dEAA diet. A 4.6% increase in tenderloin yield was observed when broilers were fed the +10% dEAA diet, but no further increase was observed with the +15 or +20% dEAA diets. Fat pad yield was observed to decrease from 1.56 to 1.11% as dEAA increased from the control diet to the +20% dEAA diet, respectively. Overall, the improvements to growth performance and processing yields observed in this study support the feeding of increased dEAA diets to Cobb 700 × MV broilers.