Asociación Latinoamericana de Producción Animal (ALPA)
Abstract
Harco Sex Link layers were used to evaluate the effects of three population densities in cages (DPJ; 600, 480, and 450 cm 2/hen) using cages of three sizes (30 x 40, 36 x 40, and 45 x 30 cm), in which were housed 2, 3, and 3 birds/cage, resulting in 15, 12, and 15 cm of lineal feeder space per bird, respectively; and two levels of dietary energy (NED; 2 600 and 2 800 kcal ME/kg) and their interaction, on feed consumption (ConA), laying percentage (PP), weight per egg (PH), and feed conversion (CA), in a 12-wk trial conducted at La Tuquerena Farm. A completely randomized design was used, with a factorial arrangement (3 x 2) and six replications per treatment. DPJ exerted effects (P < 0.05) on ConA and PP, the highest values (128.9 g/day and 65.4%) corresponding to the 600 cm2 density, whereas PH and CA were not affected. NED did not affect (P < 0.05) ConA (although trend was to higher consumption at the lower NED) nor PP and PH; the higher NED gave better (P < 0.05) efficiency in CA (expressed as 2.36 vs. 2.59 kg feed/dozen eggs or 1.91 vs. 1.96 kg/kg). The DPJ–NED interaction affected (P < 0.05) ConA, PP and CA, but not PH (treatment means of which varied only between 64.2 and 62.3 g). Highest ConA (130.4 g/day) and PP (64.6%) were obtained with the combination 600 cm 2/bird and 2 600 kcal/kg, lowest ConA (114.5 g) with 480–2 800 and lowest PP (52.1%) with 480–2 600. The best CA (kg/dozen) were 2.30 for 450–2 800 and 2.34 for 480–2 800 and the worst 2.67 (480–2 600) and 2.64 (450–2 600). The 2 600 energy level was satisfactory for use with the 600 cm 2/hen density, but at the higher densities its use resulted in lower PP and poorer CA than the 2 800 kcal/kg level
