This study was conducted to evaluate the effect of partial substitution of Noug Seed Cake (NSC) with a mix of Brewery Dried Grain and Brewery dried Yeast (BDGY) on egg qualitiesof Bovans Brown layers. A total of 120 Bovans Brown layers of 28 weeks of age, were randomly divided into 12 groups each with 10 layers of comparable body weight. Three isocaloric and iso-nitrogenous treatment rations in which 5% (T2), 10 %( T3) and 15% (T4) of NSC proteins were substituted with BDGY proteins were formulated. Commercial layers ration with 0% BDGY (T1) and similar in energy and protein content was used as positive control treatment ration. Finally the four treatment rations were randomly assigned to the experimental layers in completely randomized design with 3 replicates for study period of 12 weeks. There was no significant difference (P>0.05) between all the treatment groups in mean yolk and albumen weight, while the groups fed on the commercial layers ration was superior (P<0.05) to all the others in shell strength, shell thickness and shell weight probably attributed to better bioavailability of calcium and phosphorus of commercial ration but there was no significant difference between the other treatment groups in shell structure (P>0.05). The groups fed on the commercial layers ration was significantly lower (P<0.05) than the others in yolk and albumen height and in haugh unit. Generally, the results of this study indicate that BDGY could safely be included into layers ration to substitute up to 15% proteins of NSC in the vicinity of brewery where NSC is scarce.
Keywords: Brewery residue, oil residue, internal and external quality.