Effect of different level of lysine and metabolic energy on growth performance and nutrient digestibility in broilers with corn–soybean meal–canola meal as based diet

Two experiments were conducted to value the effects of different level of Lys and ME on growth performance and nutrient digestibility in broilers with the corn-SBM-canola meal as based diet. In Exp 1, a total of 663 broilers (initial BW, 41 ± 0.49 g) were arranged with three treatments for 5 wks: L1 (Starter, Grower, Finisher: 1.45%, 1.30%, 1.20% Lys in basal diet); L2 (Starter, Grower, Finisher: 1.50%, 1.35%, 1.25% Lys in basal diet); L3 (Starter, Grower, Finisher: 1.55%, 1.40%, 1.30% Lys in basal diet). Each treatment had 13 pens with 17 broilers per cage. This experiment consist of 3 phases: starter phase (from d 1 to 7), grower phase (From d 7 to 21) and finisher phase (from d 21 to 35). BWG was significantly improved and F/G was significantly reduced with added grade Lys from finisher phase and overall phase (P<0.05). In Exp 2, a total of 544 broilers (30 d of age, initial BW, 786.07 ± 17.26 g) were arranged with four treatments for 2 wks, as a 2 x 2 factorial arrangement of treatments in a randomized complete block design to evaluate two levels of Lys (1.20% or 1.30% Lys in basal diet) and two dietary energy (3,200 kcal /kg or 3,150 kcal /kg ME in basal diet). Four treatments: Lys 1.20% in high ME or low ME energy (3,200 kcal/kg or 3,150 kcal/kg ME in basal diet), Lys 1.30% in high or low energy. Each treatment had 8 replicate pens with 17 broilers per cage. BWG was improved in the dietary supplement of 1.30% in high energy (P=0.062). F/G was induced in the dietary supplement of 1.30% in high and low energy (P=0.006, P=0.067, respectively). However, FI was decreased in the dietary supplement of 1.30% in high energy (P=0.020, P=0.057, respectively). There is no difference in interaction during experiment period (P＞0.05). In conclusion, dietary added 1.30% Lys could increase BWG and FCR in the finisher phase of broilers.