Abstract
A total of 198 day old Arbor acres chicks and 198 Cobb300 were allotted into six groups (n=66) three for each breed, group one fed commercial broiler ration with BioGaurd (0.5g/kg ration) feed additives, group two fed commercial broiler ration with Micro-BACLA (0.5g/kg ration) feed additive and last one fed commercial ration without additives and kept as control for the same breed.
The obtained result showed that Arbor acres breed was superior than Cobb300 breeds in the final body weight (1970.0 vs. 1831.3 g), total weight gain (1914.0 vs. 1769.35g), total feed conversion ratio (1.72 vs. 1.78), total return per average bird body weight (27.88 vs. 25.93 L.E./bird), net return (2.97 vs. 1.80 L.E./bird) and net return/total cost ratio (11.92 vs. 7.45).
Regarding to the effect of feed additives, BioGaurd improved significantly total body weight (1988.67 g), total weight gain (1938.99 g), total feed conversion ratio (1.69), total return (28.14 L.E/bird), net return (3.48 L.E/bird) and net return/total cost ratio (14.11) than Micro-BACLA and control groups. Moreover, compared to control group, Micro-BACLA feed additives significantly increased total body weight (1858.63 vs. g), total weight gain (1801.18 g), total feed conversion (1.78) and total return (26.32 L.E./bird), however, Micro-BACLA significantly increased total cost (24.75 L.E./bird) which in return significantly decreased net return (1.57 L.E./ bird) and net return/total cost ratio (6.34).
The interaction between breed and dietary supplement showed that within each breed BioGaurd improved productive performance and economic efficiency than Micro-BACLA while, Micro-BACLA increased productive performance but decreased economic efficiency parameters even when compared to control group.
From our experimental work it could be concluded that Arbor acres broiler when fed commercial ration supplemented by BioGaurd had better productive performance, total return, net return and net return/total cost ratio than Arbor acres fed ration with Micro-BACLA or control without feed additives. Moreover, with Arbor acres broilers was better than Cobb300 broilers when fed commercial ration in both productive performance and economic efficiency.

Key words: BioGaurd, Micro-BACLA, Arbor acres, Cobb300, productive performance and economic efficiency.