Levels of metabolizable energy and digestible lysine for broiler chicks 1-10 days of age

This study evaluated the effect of different levels of metabolizable energy (ME) and digestible lysine (DL) on the rate of protein deposition, rate deposition body fat and intestinal morphology of broiler chicks 1 to 10 days of age. The study design consisted of 1,152 broilers, weighing 52 ± 5 g, distributed in a completely randomized, 4x4 factorial design, consisting of four levels of ME (2700; 2825; 2950 and 3075 kcal/kg) and four levels of DL (1,080; 1,187; 1,295 and 1,403%), with 16 treatments and three replicates, with 24 poultry in each experimental unit. The protein deposition rate (PDR) and fat deposition rate (FDR) were not affected (P > 0.05) by the ME, however, PDR was influenced linearly (P < 0.05) by increasing lysine. There was an interaction (P < 0.05) between the levels of ME and DL, whose increase resulted in a higher villus height of the duodenum, jejunum and a greater relation villus: crypt ratio of the ileum. Therefore, levels of DL and ME had positive effects on the intestinal development of broiler chicks in the pre-starter phase.