Study On Anti-nutritive Mechanism Of Wheat NSP And Application Of Xylanase Supplemented In Wheat-based Diet For Broilers

Five trials were conducted to investigate the anti-nutritive mechanism of wheat NSP and ileal digestibility of nutrients fed wheat-based diet and the equivalent relationship between xylanase and ileal AME in broilers.Exp. 1 Effects of wheat NSP and xylanase on performance, relative weight of immune and digestive organs, serum hormones concentration in broilers. 360 AA broilers were allocated randomly into 3 groups, fed 3 diets separately. The diets were corn based, wheat-based or wheat-based supplemented with xylanase. The results showed, the wheat-based diet reduced (P<0.05) the weight gain by 8.23%, addition of xylanase in wheat-based diet increased weight gain by 9.12% (P<0.05). Feeding the xylanase-supplemented diet increased the FCR by 10.87% (P<0.05). The relative weight of spleen, bursa of fabricius, thymus was increased by addition of xylanase. The relative weight of Pancreas, Liver, Intestine, proventriculus and gizzard was decreased by supplementation xylanase in wheat based diet. The viscosity of intestinal digesta was decreased (P<0.05) by 30% with supplementation xylanase in wheat based diet. The results of serum hormones indicated that, at the end of 28 days, the wheat-based diet reduced (P<0.05) significantly the serum level of INS, Feeding the xylanase-supplemented diet increased (P>0.05) the level of INS. There is no significantly differences (P>0.05) in serum levels of hormones between three treatments except the INS.Exp. 2 Effects of wheat extracted pentosans on endogenous nitrogen and amino acid losses in 35 days broilers by enzyme-hydrolyzed casein and ultrafiltration technique. 60 broilers were allocated randomly into 3 groups, fed 3 diets separately. These diets were purified diet, purified diet supplemented with 4% WEP or 4% AEP. The results indicated that the addition of extracted pentosans in purified diet significantly increased (P<0.05) ilea! endogenous losses of nitrogen and amino acids. Increasing amino acid losses were found in AEP added diet than that of WEP added diet and control treatment (no pentosans addition). The losses of the amino acid in broilers supplementation with 4% AEP or 4% WEP as much as 3.42 times ard 2.71 times than that of control treatment. Addition of 4% AEP increased the losses of the amino acid by 26% than that of addition of 4% WEP. The results showed that the effects on apparent protein digestibility was not only due to an increasing of endogenous amino acid losses but also a direct inhibition of protein breakdown and amino acid absorption.Exp. 3 Effects of wheat NSP and xylanase on intestinal microflora and bacterial community in broilers by traditional method and denaturing gradient gel electrophoresis (DGGE) analysis of I6S ribosomal RNA. 90 AA broilers were allocated randomly into 3 groups, fed 3 diets separately. The diets were same as that of the exp.l. The results showed that the wheat NSP significantly increased (P<0.05) the microbial population of total anaerobic bacterias in cecum or ileum and increased (P<0.05) theiiistreptococcus faecalis in cecum of broilers. However, the wheat NSP significantly decreased (P<0.05) the bacterial community in intestine of broilers. The xylanase-supplemented diet had no markedly effect (P>0.05) on microbial population and bacterial community in cecum and ileum of broilers.Exp. 4 Effects of xylanase on serum lipid levels and HMG-COA reductase mRNA expression in wheat based diet in broilers. 120 AA broilers were allocated randomly into 3 groups, fed 3 diets separately, the diets were same as that of the exp. 1. The results indicated that the wheat-based diet decreased the serum levels of TC, LP, HDL-C (P>0.05) than that of corn-based diet. The xylanase-supplemented diet significantly increased (P<0.05) the serum levels of TC and HDL-C. There is no significantly difference in serum levels of TG and LDL-C between three treatments. The liver HMG-COA reductase mRNA expression was decreased in wheat-based diet than that of corn-based diet (P>0.05). The xylanase-supplemented diet increased (P>0.05) liver HMG-C...