Effects of metabolizable energy and crude protein levels on laying performance, egg quality and serum biochemical indices of Fengda-1 layers

摘要

Abstract This study was conducted to investigate the effects of dietary {ME} and {CP} levels on laying performance, egg quality and serum biochemical indices of Fengda-1 layers. In a 2?×?3 factorial arrangement, 2,400 Fengda-1 layers (32?wk of age) were randomly assigned to 6 experimental diets with 2,650 and 2,750?kcal of ME/kg of diet, each containing 14.50%, 15.00% and 15.50% CP, respectively. Each dietary treatment was?replicated 5 times, and feed and water were provided ad libitum. The trial lasted for 10 wk, including a 2-week acclimation period and an 8-week experimental period. Our results showed that {ADFI} decreased as the {ME} level of diet increased from 2,650 to 2,750?kcal/kg (P??0.05). Based on the data under the experimental conditions, the optimal dietary {ME} and {CP} levels of Fengda-1 layers are 2,650?kcal/kg and 15.00% (33 to 41?wk of age).