This experiment was conducted in the poultry field in department of animal production -colleg of agriculture at Kirkuk university for the period from 1/12/2018 to 29/1/2019 to determine the effect using three levels(0.50,1.00 and 1.5%) laurel leaves powder with or with out of supplementation 0.10% of prebiotic(dry yeast bread) upon the layer performance and the quality and sensory traits of the ISA BROWN layer egg. Randomly fed 112 layers at 60 weeks old with 8 experimental diets and layers keeped in the cages (dimmesions 37x30x45 cm length, width and height respectively).for the battery included 4 floors and each floor contained three cages (three replicates).Each treatement included 7 replicates (cages) and 2 layer were kept at each cage.
The feed and water was available for birds during the experiment period (60 days) and nutritional treatements were as following:T1:Control diet(basal diet with out adding the laurel leaves powder and the prebiotic (dray yeast bread).T2:the basil diet contained 0.10% of prebiotic.T3:the basil diet contained 0.50% of the laurel leaves powder T4:the basil diet contained 1.00% of the laurel leaves powderT5:the basil diet contained 1.50% of the laurel leaves powder T6:the basil diet contained 0.50% of the laurel leaves powder with 0.10% of prebiotic T7:the basil diet contained 1.00% of the laurel leaves powder with 0.10% of prebiotic T8:the basil diet contained 1.50% of the laurel leaves powder with 0.10% of prebiotic.
The results of statistical analysis obtained no significant differences among treatement for the egg production , while noted significant(P≤ 0.05)increasing the egg weiht for T5 birds (69.46 gms/egg) by comparing with the control treatement bird .The egg mass for the treatements (2,3 and 5) layers significantly (P≤ 0.05) heaviour (63.70,63.02 and 63.35)gm egg/bird per day than the control treatement layers (54.87) gm egg per day per bird .the feed conversion ratio for tfe third treatement was significantly(P≤ 0.05)better(1.85)than the control birds (2.19).There were no significant variation among the birds of the experiment treatements for the intake of the feed ,energy and protein ,and the lysin conversion ratio .
There were no significant differences among the quality traits of the eggs (shell thickness;egg shape index and hugfi unit,in the sesory traits of the egg noted increasing in the value of the texture trait for the control and eigth treatements by comparing that with another treatamants.The relative weight of the birds heart was higher significantly (P≤ 0.05) for the birds of the 4 and 7 treatements than the birds of the 2and6 treatements .
The better economic return was for the second treatemant birds as the cost of feed for one kilogram of the eggs which was produced.