杨木低聚木糖对肉鸡生长性能、肠道消化酶活性和短链脂肪酸含量及血清激素水平的影响

本试验以肉鸡为研究对象,对以杨木屑为原料、采用醋酸催化法制取的低聚木糖进行评价,研究低聚木糖对肉鸡生长性能、肠道消化酶活性和短链脂肪酸含量及血清激素水平的影响,探讨低聚木糖的促生长机制,为醋酸催化法生产低聚木糖的应用提供理论依据。选用120只1日龄爱拔益加肉公鸡,随机分为2个组,即对照组和低聚木糖组,每组6个重复,每个重复10只鸡。对照组饲喂基础饲粮,低聚木糖组以0.02%低聚木糖等量替代基础饲粮中的沸石,试验期为42 d。结果表明:1)与对照组相比,饲粮添加低聚木糖显著提高了肉鸡42日龄时的体重以及22~42日龄和1~42日龄的平均日增重(P<0.05),显著降低了料重比(P<0.05),对平均日采食量无显著影响(P>0.05);2)与对照组相比,饲粮添加低聚木糖显著提高了肉鸡十二指肠脂肪酶活性(P<0.05),有提高十二指肠蛋白酶活性的趋势(P=0.056),但对空肠、回肠和盲肠脂肪酶和蛋白酶活性无显著影响(P>0.05);3)与对照组相比,饲粮添加低聚木糖对盲肠短链脂肪酸含量无显著影响(P>0.05);4)与对照组相比,饲粮添加低聚木糖显著增加了肉鸡血清生长激素和三碘甲腺原氨酸(T 3)含量(P<0.05),显著降低了血清甲状腺素(T 4)含量(P<0.05),显著降低了T 4/T 3值(P<0.05)。综上所述,低聚木糖通过提高肠道消化酶活性,促进与生长相关的激素分泌,提高营养物质利用率,从而改善肉鸡的生长性能。

Effects of Xylo-Oligosaccharides from Poplar on Growth Performance,Intestinal Digestive Enzyme Activity and Short-Chain Fatty Acid Content and Serum Hormone Levels of Broilers

This study was to identify the effects of xylo-oligosaccharides(XOS)from poplar sawdust by acetic acid catalysis method on growth performance,intestinal digestive enzyme activity and short-chain fatty acid(SCFA)content and serum hormone levels of broilers,and investigate its growth-promoting mechanism,thus to provide theoretical basis for the application of acetic acid catalysis method to produce the XOS.One hundred and twenty 1-day-old male Arbor Acres broilers were randomly divided into 2 groups(control group and XOS group)with 6 replicates in each group and 10 birds in each replicate.The diets consisted of a basal diet for the control group and an experimental diet supplemented with 0.02%XOS to replace the zeolite in the basal diet with equal proportion for the XOS group.The trial lasted for 42 days.The results showed as follows:1)compared with the control group,dietary XOS significantly increased the body weight of broilers at 42 days of age and the average daily gain of broilers from 22 to 42 and 1 to 42 days of age(P<0.05),significantly decreased the feed to gain ratio(P<0.05),but had no significant effects on the average daily feed intake(P>0.05).2)Compared with the control group,dietary XOS significantly enhanced the lipase activity in duodenum of broilers(P<0.05),tended to increase the protease activity in duodenum(P=0.056),but had no significant effects on the activities of lipase and protease in jejunum,ileum and cecum(P>0.05).3)Compared with the control group,dietary XOS had no significant effects on SCFA content in cecum of broilers(P>0.05).4)Compared with the control group,dietary XOS significantly increased the serum contents of growth hormone and triiodothyronine(T 3)of broilers(P<0.05),significantly decreased the serum thyroxine(T 4)content(P<0.05),and significantly decreased the T 4 to T 3 ratio(P<0.05).In conclusion,XOS can improve the growth performance of broilers by enhancing the digestive enzyme activity,promoting the levels of hormones related to growth and then increasing the nutrient availability.