the effect of dietary protein and lysine on egg quality and production of laying hens during 28-42 weeks of age

an experiment was conducted to evaluate the effect of dietary crude protein and lysine levels on quality and quantity of egg production. fifteen diets consisted of 3 levels of protein (14, 15 and 16%) and 5 levels of lysine (0.71, 0.74, 0.77, 0.80 and 0.83 %) in a 35 factorial arrangement were provided. each diet was randomly fed to 4 replicates of 12 birds, during four periods of 4 weeks (28-44wks of age). egg number and mortality was recorded daily, whereas feed consumption determined for each period. eggs from each replicate were weighed at the end of three consecutive days of each period and six eggs were used to measure the egg quality characteristics. although the feed intake did not affected by dietary protein but the egg production, egg mass and feed conversion were improved significantly (p<0.05) as the level of dietary protein increased from 14 to 16. increasing the level of dietary protein from 14 to 16% improved egg mass by about 1.9g; the level of dietary lysine did not have an effect on egg production, egg weight, egg mass, specific gravity and feed conversion.