Abstract: The experiment was divided into 4 groups: corn diet as the control group, wheat diet, wheat diet supplemented xylanase, fermented wheat diet as the test group. 360 one-day-old AA broiler chickens were selected and they were randomly divided into 4 groups, 3 repeats each group, 30 chickens each repeat, male and female mixed. The pre-feeding period was a week. It went into the test period in the second week. They were slaughtered on the fourth weekend. The production performance, immune organ index, blood parameters, digesta viscosity were determined, and cecal contents were separated colonies. The results showed: ①Production performance,7 to 14 day-old, the average daily weight gain on fermented wheat diet was lowest than other (P<0.01), feed efficiency was highest than other (P<0.01),wheat diet and wheat diet supplemented xylanase feed efficiency was no signifficent difference,but higher than corn diet(P<0.01). 15 to 22 day-old, the average daily weight gain on fermented wheat diet was lowest than other (P<0.01), corn diet and wheat diet supplemented xylanase average feed intake was no signifficent difference(P>0.05), but higher than fermented wheat diet and lower than wheat diet (P<0.01). Corn diet and wheat diet supplemented xylanase feed efficiency was no signifficent difference (P>0.05), wheat diet and fermented wheat diet feed efficiency was no signifficent difference (P>0.05),but the frist two groups lower than behind two groups. 23 to 30 day-old , the average daily weight gain on fermented wheat diet was lowest than other (P<0.01), corn diet and wheat diet supplemented xylanase feed efficiency was no signifficent difference (P>0.05),but higher than Fermented wheat diet and lower than wheat diet(P<0.01),fermented wheat diet feed efficiency higher than corn diet and wheat diet supplemented xylanase,but lower than wheat diet(P<0.01). ② Immune organs index: fermented wheat diet spleen index was the higher than wheat diet supplemented xylanase (P<0.05). Fermented wheat diet Thymus index was the higher than wheat diet(P<0.01), corn diet and wheat diet supplemented xylanase was no signifficent difference(P>0.05).③ Colony isolation cecal contents showed: no significant difference in the total number of anaerobic bacteria and lactic acid bacteria (P>0.05), wheat diet supplemented xylanase E.coli was less than the corn diet(P<0.05), but the total number of the other groups of lactic acid bacteria was no significant difference (P>0.05). ④Fermented wheat diet T3, T4, and blood glucose were lower than corn diet,wheat diet and wheat diet supplemented xylanase (P<0.01), uric acid were higher than corn diet,wheat diet and wheat diet supplemented xylanase (P<0.01). ⑤Tissue slice showed: wheat diet liver lymph cells hyperplasia,spleens have congestion,other groups had no signifficent difference.

Key words: diet; broiler chicken; production performance; immune organs; blood parameters; digesta viscosity