Programa de luz e forma física da ração pré-inicial para pintainhas de postura: composição e deposição de nutrientes corporais

Abstract

The work was developed with the objective of evaluating the effects of the light program and the physical form of the pre-starter ration on the deposition and retention of body nutrients in chicks from two lines of commercial layers. For this, 960 one-day-old chicks were used, half from each of the evaluated lines (Hisex White and Hisex Brown), up to the second week of age. At one day of age, the birds were weighed individually and selected to obtain experimental plots with homogeneous average weight and then distributed in a completely randomized design, with eight treatments, six replications and 20 birds per experimental plot. The treatments were designed according to a 2 x 2 x 2 factorial, in which the following were evaluated: two light programs for the initial phase (continuous and intermittent), two physical forms of the pre-starter feed (mash and pelletized) and two strains. The comparative slaughter methodology was used to determine the retained crude protein, retained ether extract and mineral matter in the body. Thus, at the beginning of the experiment, six birds were euthanized to determine the initial body composition and at 14 days of age, one bird from each repetition was euthanized, with the weight close to the average weight of the plot, to determine the final body composition. According to the results obtained, there were no significant interactions between the evaluated treatments and no influence of the light program on the evaluated parameters. It was found that pellets favor performance and allow greater deposition of body fat in light and semi-heavy chicks. In relation to the lines analyzed, light birds proved to be more efficient in using the feed consumed to gain weight compared to semiheavy birds.