Effects of dietary energy level and 1,3-diacylglycerol on growth performance and carcass yield in broilers

An experiment was conducted to evaluate effects of dietary energy level and 1,3-diacylglycerol (DAG) on growth performance and carcass characteristics in broilers. A 2 X 2 completely randomized factorial arrangement was used in this study with Cobb standard or reduced levels of dietary energy and inclusion of DAG at 0 or 0.1%. For the standard-energy group, ME was formulated to 3,000, 3,100, and 3,150 kcal/kg for starter (day 0-7), grower (day 8-21), and finisher (day 22-42) periods, respectively. In the reduced-energy diet, ME was reduced by 75 kcal/kg for each period. A total of 640 1-day-old Cobb500 male broilers were randomly placed into 4 treatments with 8 replicate pens of 20 birds each. At day 43, 8 birds from each pen were selected for carcass yield. A reduction of dietary energy decreased (P < 0.05) BW gain and increased (P < 0.05) feed conversion ratio compared with the standard-energy group during 0 to 35 and 0 to 42 D. Inclusion of DAG at 0.1% increased (P < 0.05) BW gain during 0 to 35 and 0 to 42 D and decreased (P < 0.05) feed conversion ratio during 0 to 35 D compared with the reduced-energy group. There were interactions between DAG and energy level on most carcass weight parameters (P < 0.05). The interaction effects suggested reduced-energy group without adding DAG had a negative effect on the carcass parameters compared with standard-energy control group. Adding 0.1% DAG to the reduced-energy diet was able to improve the carcass parameters through increasing live weight. It is concluded that reduction of dietary energy level and crude fat reduced performance and DAG supplementation could improve performance.