Programas de luz para pintainhas de postura leves e semipesadas alimentadas com ração pré-inicial farelada ou peletizada

Abstract

The objective of this study was to evaluate the effects of lighting programs during the initial phase, as well as the physical forms of the pre-initial feed, on the performance of light and semiheavy laying pullets. A total of 720 one-day-old pullets were used, with half of each of the evaluated strains. The birds were distributed in a completely randomized design with six treatments, six repetitions, and 20 birds per experimental unit. The treatments were designed according to a 2 × 2 × 2 factorial, where two lighting programs (continuous and intermittent) during the initial phase, two physical forms of pre-initial feed (mash and pelleted), and two strains (light and semi-heavy) were evaluated. The birds were fed pre-initial feed in different physical forms until they were 14 days old. After that, the birds from all treatments received the same feeding program and feed type, with feed provided specific to each phase in the mash form. Throughout the experimental period, the birds had free access to feed and water, and weekly, until the seventh week, feed intake (g/bird), final average weight (g), weight gain (g), and feed conversion were determined. The uniformity of the birds was also assessed in the second, fifth, and eighth weeks of age, with individual weighings of the birds from each unit. Semi-heavy birds showed greater potential for weight gain compared to light birds. The intermittent light program offered from 1 to 35 days of age did not affect the performance of light birds, while it impaired the performance of semi-heavy birds. Regardless of the light program used, the use of pelleted pre-initial feed improved the performance of both light and semi-heavy pullets