Modelagem da exigência de lisina e deposição de nitrogênio para frangas de crescimento lento

Abstract

The objective of this study was to estimate the demand of nitrogen and the deposition of lysine to females broilers of slow growth, the Redebro broilers lineage. Three nitrogen balance assay were carried out in phases: initial (13-27 days), growth (42-56 days) and late (72-91 days), with a total of 126 birds, 42 per period. The birds were housed in individual cages equipped with trays for holding excreta collection, trough feeder and drinker type nipple with cup, and distributed according to a completely randomized design with six treatments and six replications. The treatments were: NI = 5%, N2 = 10% = 15% N3, N4 = 20% = 25% N5 and N6 = 30% of CP. The diets were according with requirements of the birds for each period, except for lysine, which had a limitation of 20% on each diet. The experimental period was 15 days in the three trials, with the first 5 days for adaptation and the other 10 days for total feces collection. The diets and excreta were analyzed for nitrogen and quantification of intake and nitrogen excretion, and you can then calculate the nitrogen retained. Based on adjustments to the equations of Goettingen model was able to estimate the nitrogen requirement for maintenance (236, 211 and 138 mg / PV0,67), the maximum potential nitrogen retention (2,992, 1,952 and 1,984 mg / PV0, 67) and the consumption of digestible lysine (436, 472 and 725 mg / PV0,67), whereas 60% ND