A factorial experiment was conducted to investigate the response of laying hens to various levels of dietary energy and protein. Varying levels of dietary energy (2700, 2800, and 2900 Kcal ME/Kg) each at four protein levels (14,15,16 and 17%) were fed to 1152 27 week-old laying hens. Birds were randomized into cages, with each of the 12 experimental treatments consisting of 8 cages and 4 replicates. All birds were given free access to water and diets. Egg production, egg output, and feed efficiency were not significantly affected by either dietary energy or protein contents or ME by protein interaction (P<0.05), even though they tended to increase with increase in energy level. Dietary treatments did not exert any significant effect on feed conversion, feed per dozen eggs, albumen index, cracked and soft-shell eggs and mortality. Dietary protein affected egg weight (P<0.01), although there was no significant difference between protein levels of 15,16 and 17 %. The egg weight with proteins ranging from 14 to 15 and 17% was increased from 57.5 to 58.6 and 58.8 g, respectively. Feed intake reduced as energy level of the diet was increased (P<0.05). Feed intake was 2.5 g lower when dietary energy was raised form 2700 to 2900 Kcal/Kg (P<0.05). Feed cost per Kg egg weight increased with highest energy level (P<0.01). Financial returns were less (P<0.05) for hens fed on 2900 Kcal ME/ Kg and tended to increase non-significantly with decrease in protein level. There was also a significant energy effect observed (P<0.01) on egg shell quality. Pre- and post experiment body weights were taken at 27 and 40 wks of age. Alterations in dietary ME concentration had no influence on body weight change, however, it was affected (P<0.01) by protein levels. Maximum hen-day egg production, egg output, feed efficiency, and lowest feed cost per Kg egg weight were obtained on the ration containing 2800 Kcal ME/Kg and 15% protein.
)