Efeito de diferentes níveis de proteína bruta e energia metabolizável sobre o desempenho e a bioquímica sérica de frangos de corte, no Semiárido Paraibano.

Abstract

The objective of this work was to evaluate the performance and biochemical profile of broilers submitted to different levels of crude protein and metabolizable energy in their diet, estimating the requirements of these nutrients for each breeding phase. 450 animals were used in a DIC in a 3x3 factorial scheme (metabolizable energy and crude protein levels) with five replicates and ten birds per experimental plot, totaling forty five experimental units. In phase 1, from 1 to 7 days (pre-start) were 21.20; 22.20 and 23.20% of crude protein and 2900, 2950 and 3000 kcal of metabolizable energy. In phase 2, from 8 to 21 days (initial), 19.80; 20.80 and 21.80% crude protein and 2950, 3000 and 3050 kcal / kg metabolizable energy. In stage 3, from 22 to 35 days (growth) 18.50; 19.50 and 20.50% crude protein and 3050, 3100 and 3150 kcal metabolizable energy. In phase 4, from 36 to 42 days (final), 17.50; 18.00 and 18.50% crude protein and 3100, 3150 and 3200 kcal metabolizable energy. For the biochemical profile, urea, uric acid, cholesterol, total protein and albumin were measured. Serum biochemistry results were mostly within the reference range for the species, with only urea difference (above reference values) in all treatments. The use of 23.20% of crude protein and 2950 Kcal of metabolizable energy during the pre-initial phase, 21.8% crude protein and 3050 Kcal were recommended for the formulation of broiler diets grown in the Paraiba semiarid region. Of metabolizable energy during the initial phase, 20.5% of crude protein and 3150 Kcal of metabolizable energy during the growth phase and 18% of crude protein and 3100 Kcal of metabolizable energy during the final phase.