Effects of B-Mannanase Supplementing of Olive Pulp-Included Diet on Performance of Laying Hens, Egg Quality Characteristics, Humoral and Cellular Immune Response and Blood Parameters

The objective of this investigation was to evaluate performance of laying hens fed olive pulp (OP)- included diets supplemented with a commercial -mannanase-based enzyme product. A total of 144 laying hens (75-wk old Lohman-LSL Lite) were assigned to feed 6 experimental diets with 4 replicates (cage) and 6 hens per cage. A 3×2 factorial arrangement of treatments including 3 levels of OP (0, 4.5 and 9.0 %) and enzyme (Hemicell 0 and 0.05%) was employed for 9 wk trial period. Collected data was analyzed based on completely ® randomized design using GLM procedure of SAS. Diet inclusion of OP and enzyme had no significant effect on overall egg production, egg mass, feed conversion ratio and feed intake (p>0.05). Hens fed diet with 9% OP and enzyme had the highest egg weight compared to hens fed other experimental diets (p<0.05). Decreased Haugh unit was seen in hens fed diet included 9% OP compared to hens fed other experimental diets (p<0.05). Egg shell weight in the birds fed OP-included diets was higher than the birds fed control diet (p<0.05). Dietary enzyme supplementation had no significant effect on egg quality characteristics. In conclusion, based on the results of the present experiment OP can be included laying hens diets up to 9 % with no deleterious effects on bird's performance. In addition, dietary OP could improve egg weight.