The analysis was conducted to compare the effects of XG with AG and BM at different metabolizable energy diets on growth performance, digestive physiology and energy utilization of broilers fed with corn-SBM diet. were significantly increased by XG or AG in NC diet. The villus length and V/C of ileum were significantly increased by the addition of BM or XG. XG improved the activities of trypsin, chymotrypsin and amylase, BM improved the activity of trypsin at 21d, and AG improved the activity of chymotrypsin at 21d. Comparing to PC diet, the addition of enzymes in PC or NC diet decreased feed cost per kg body weight gain especially in NC diet (except AG in PC diet) with the highest profits for XG in NC diet. In conclusion, supplementation of 0.02% BM or 0.01% AG or 0.05% XG could improve feed conversion of broilers in corn-soybean meal diet by improving energy utilization and digestive physiology, and also supplementation of 0.05% XG had a preferable efficacy in low energy diet. <0.05) at 0-21d and by 6.3%, 8.1% and 8.5% respectively (<0.05) at 22-42d. Compared to the PC diet, addition of BM in PC diet significantly improved F/G by 4.9% at 0-21d (<0.05). Table 3 Effects of exogenous enzymes and diet on the BW and BWG of broilers Table 4 Effects of exogenous enzymes and diet on the FI and F/G of broilers TME results Result for AME, TME, and dry matter output were presented in Table?5. The dietary AME and TME were influenced significantly by the diet or the addition of enzymes (<0.05). NC diet had significantly lower AME (?8.1%) or TME (?6.9%) than PC diet (<0.05). The addition of XG significantly increased the AME (+3.9% in NC diet, +14.6% in PC diet, <0.05), and TME (+3.3% in NC diet, +12.5% in PC diet, <0.05), while the addition of AG significantly increased AME and TME in NC diet but significantly decreased the AME and TME in PC diet (<0.05). The addition of XG in PC diet significantly decreased the dry matter output (<0.05). Table 5 Effects of exogenous enzymes and diet on the energy utilization of diet (air dry basis) Intestine morphology Results for duodenum morphology were shown in Table?6. The crypt depth was significantly decreased by the addition of enzymes in the PC diet (?7.9%) at 21d, and decreased with the addition of AG in the PC diet at 21 d (?16.6%) (<0.05). The V/C was significantly increased by PC diet (+9.7%) at 21 d, and the addition of AG increased V/C (+19.3%) (<0.05) at 21d. Table 6 Effects of exogenous enzymes and diet on duodenum morphology in broilers The data of effect of the dietary treatments on ileum morphology were shown in Table?7. The villus length, crypt depth (except at 21d) and V/C were significantly influenced by the addition of enzymes, diets (except the villus length at 42d) or their interactions (<0.05). At NVP-BAG956 21d, the villus length was significantly increased by 53.7% and 40.4% with NVP-BAG956 the addition of BM and XG in PC diet and the V/C was significantly increased by 72.3% and 51.8% with NVP-BAG956 the addition of BM and XG. NC diet significantly decreased the villus length by 15.5% at 21d, but increased the V/C by 22.4% at 42d (<0.05). The crypt depth was significantly increased by the addition of enzymes in PC diet and by PC diet at 42d. The addition of BM and XG significantly decreased the V/C in PC diet, NVP-BAG956 while significantly increased by AG at 42d (<0.05). Table 7 Effects of exogenous enzymes and diet on ileum morphology CCL2 in broilers Digestive enzyme activities The data of effect of the dietary treatments on digestive enzyme.