This experiment was conducted to evaluate the effects of partial or complete replacement of okara meal for soybean meal on broiler performance, nutrients digestibility and economic efficiency. A total number of 350 one-day-old unsexed Ross chicks of nearly similar live body weight (45 g.) were randomly divided into equal five treatments; each contained 70 birds in seven replicates of ten birds each. Five experimental diets were formulated to be approximately iso-caloric and iso- nitrogenous according to the management recommendation guide data (Ross).
Birds were fed starter- growers (1-4 weeks) and finisher (5-7 weeks) diets ad lib and had free access to water for the entire experimental period. The results showed that the whole experimental period, feeding graded levels of okara meal replacing for soybean meal at levels of either 25,50 and 75 % in broiler diets had no significant effect on live body weight gain (BWG), feed conversion rate (FCR) and average live body weight (LBW) compared with control group. However, the differences were significant poorest (P<0.05) as replacing okara meal for soybean meal at a level of 100% compared to control group or other treatments. There were significant decreases (P<0.05) feed intake values due to using different levels of okara meal compared to control group. Results showed a significant increase (P<0.05)in average values of EE and CF digestibility and N retention with using okara meal as replacing for soybean meal at levels of 25,50 and 75% while, the use of high level (100%) significantly decreased most of nutrient digestibility coefficient and nitrogen's balance. The obtained results showed that replacing of soybean meal by okara that replacing soybean meal by okara meal in broiler diets up to level of 75% can reduce cost of feeding, save a considerable amounts of expensive ingredients and meal at levels of 25, 50 and 75% in broiler diets had no significant effect on carcass traits of chicks, while full replacement had a significant adverse effect. The results indicated prevent environmental pollution.