Improving productive and reproductive performance of dual-purpose crossbred hens in the tropics by lecithin supplementation.

In order to study the influence of lecithin and vegetable oils on improving productive and reproductive performance, egg quality, and metabolic profile of dual-purpose crossbred hens in the tropics, a total of 224 hens, 47-wk old, 112 each of Gimmizah and Silver Montazah strains were fed seven isonitrogenous diets. Experimental treatments consisted of feeding seven different diets to layers; four isocaloric diets containing either no added lipid (control), 3% vegetable oil mixture, 3% soy lecithin or 6% soy lecithin; and three high-energy level diets, containing an extra 3% vegetable oil mixture, 3% or 6% soy lecithin added to the control diet. Thus, the experimental design was factorial, consisting of seven lipid treatments by two strains of hens. Results indicate that 3% lecithin as an extra ME source, or feeding 11.72 MJ ME/kg diet containing the same level of lecithin, improved productive and reproductive performance of crossbred hens. Moreover, lecithin at 6% as an extra ME supplement significantly increased yolk percentage and improved Haugh unit score and yolk color, while increasing EE digestibility and plasma total lipids. Hen strain had a significant effect only on digestibility of OM, percentage liver and Haugh unit score, with the Gimmizah strain having higher values.