Evaluation of the effects of rations with different levels of metabolizable energy on performance of laying hens

This study was conducted to evaluate the effects of rations with different levels of energy on performance of laying hens. The experiment was conducted with two hundred and fifty six laying hens of commercial Hi-Line W-36 strain in a completely randomized design with 4 treatment and 4 replicates (16 laying hens in each replicate). Treatments included: (1) diet with amount of metabolizable energy recommended by NRC 1994 (as control group), (2) diet with 10% higher level of metabolizable energy than recommended by NRC 1994, (3) diet with 10% lower level of metabolizable energy than recommended by NRC 1994 and (4) diet with 15% lower level of metabolizable energy than recommended by NRC 1994 that were used for 10 weeks (from 41 to 51 weeks of age). The results indicated that the amount of feed intake was significantly different among treatments (p