عنوان مقاله [English]
One hundred forty-four 26-wk-old white Hy-Line layers (W-36) were fed commercial diets containing 0, 1.5, 3 and 5% surplus date for three period of 28 days each to study the effects of dietary surplus date on hen performance (egg production, egg weight, egg mass, feed intake, feed conversion ratio ‘FCR’ and body weight gain) and egg quality parameters (Haugh unit score, yolk colour index, yolk index, egg shape, shell weight, shell thickness and density). The yolk of eggs extracted and cholesterol content were determined on one egg of each replicate hens in each period. Blood samples were collected in non-heparin zed tubes from six hens in each treatment through brachial vein at the end of experiment. Serum was separated after 8-10 hrs and was stored at – 20 oC for subsequent analysis.
Hen performance (egg production, egg mass, feed intake, FCR and weight gain) and egg quality parameters (Haugh unit score, yolk colour index, yolk index, egg shape, shell weight, shell thickness and density) were not significantly different among treatments (P>0.05); However in all traits, the control group had numerically lower value, except egg weight that was significantly increased with supplementation of surplus date in diet. The dietary surplus date did not significantly affect egg cholesterol, ND and IBD titre, but the serum cholesterol was significantly reduced in hens fed diets contained 5% surplus date. This study suggested that the surplus date may be used up to 5% in the diet of laying hens to reduce blood cholesterol without any significant adverse effect on performance.