Evaluation of beak trimming methods during rearing phase on commercial lots of laying hens pullets
2017-08-07T18:33:41Z (GMT) by
The aim of this study is to analyze the coefficients that represent the energy partition ingested by Japanese quails for maintenance and egg production. A trial will be conducted to evaluate egg mass (MO) and body weight (PC) responses of Japanese quails submitted to different metabolizable energy intakes (IEM). It will be utilized a total of 70 Japanese quails, randomly distributed with seven treatments and ten replicates, composed of one bird each, for individual control. The trial will begin at 16 weeks of age and data will be collected for eight weeks. Two diets will be formulated, one with high energy content (3,600 kcal / kg - N7) and the other with low energy content (2,100 kcal / kg - N1). Intermediate levels will be obtained by dilution. The analyzed variables will be IEM, PC and MO. The models available in the literature that predict IEM based on the nutritional constants that represent the energy requirement kcal per g of MO and kcal per kg of PC will be evaluated through the linear decomposition of the error (observed - predicted), in scalar error and bias of predicted by linear regression between predicted errors and values. The decision rule will be based on the impartiality of the model, obtained when the R² approaches 0. If necessary, parameter adjustments can be made to recommend a model that allows the user to predict metabolizable energy intake according to the mass production of eggs and body weight of each farm.