Performance of broiler chickens at pre starter and starter phases using diets with different metabolizable energy values of ingredients, at different ages

摘要

The experiment was carried out to evaluate the performance of broilers in 1-7 and 8-21 days of age, using metabolizable energy values of corn, soybean meal and soybean oil previously determined for each phase in another metabolism trial. Two trails were conducted, divided into phases according to ages: pre-starter (1-7 days) and starter (8-21 days). At each trial were used 924 broiler chicken randomly distributed into 42 experimental units in a completely randomized design with six treatments and seven replications. Treatments consisted of five diets using the values of apparent metabolizable energy corrected for nitrogen balance of corn, soybean meal and soybean oil determined in different metabolism trials, and one diet with the metabolizable energy values of these same ingredients, published on the literature. At the end of each stage, the animals and feed leftover were weighted to determine feed intake, weight gain and feed conversion ratio. Diets with higher soybean oil inclusion, showed superior performance at different stages. At pre-starter only feed conversion ratio was significant (P<0.05). In the initial phase, there was a significant difference (P<0.05) for feed conversion ratio, daily and average weight gain.