An experiment was conducted to evaluate the extracted (ES) and mechanical (MS) soybean meals two levels 25% and 35% in broiler chicken feeding. Three hundred and fifty two one-day-old unsexed Lohman chickens were placed in four treatments by 4 replicates and 22 chickens in each in a 2×2 factorial arrangement. Feed intake was increased significantly in starter period by ES in comparison with MS. Feed conversion ratio was significantly improved when 25% of ES was replaced by fish meal compared

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... h 35% of ES in starter period. Body weight was significantly higher by 25% ES replaced by fish meal in comparison with 25 and 35% MS in grower period. Metabolizable energy was declined in all options (AME, AMEn, TME and TMEn) in MS than ES. Significant depressing in jejunum length was observed by 35% in the two types of soybean meal compared with 25% mechanical soybean meal replaced by fish meal in 14 days. In more details, villous length was lower by mechanical soybean meal in comparison with ES. Alkaline phosphatase enzyme activity was significantly higher in 35% ES in comparison with 25% ES replaced by fish meal and 35% MS in 14 days. In contrast, alkaline phosphatase enzyme activity was reduced remarkably by 35% mechanical soybean meal compared with 25% extracted soybean meal replaced by fish meal in starter period. Urease activity in extracted soybean meal (0.07) was lower than mechanical soybean meal (0.22). The results of this study have shown better performance by extracted soybean meal compared with mechanical soybean meal. In spite of this, less expensively processed mechanical soybean meal (MS) at 25% level replaced by fish meal could be more economical in broiler chicken feeding.