低聚糖对断奶羔羊瘤胃菌群的影响

Effects of Oligosaccharides on Rumen Microflora Flora of Weanling Lambs

本试验旨在研究低聚糖对断奶羔羊瘤胃菌群的影响。选取日龄、体重相近的陶赛特F2代断奶公羔40只,随机分成4组(每组10个重复,每个重复1只),分别为对照组(基础饲粮)、低聚异麦芽糖(IMO)组(基础饲粮+0.3%IMO)、低聚果糖(FOS)组(基础饲粮+0.3%FOS)和混合低聚糖组(基础饲粮+0.2%IMO+0.1%FOS),试验期42d(预试期7d,正试期35d)。采用变性梯度凝胶电泳(DGGE)技术对羔羊瘤胃内容物细菌16SrRNA的V6～V8可变区进行菌群多样性分析,利用实时定量PCR技术对瘤胃总菌、黄化瘤胃球菌(R.flavefaciens)和产琥珀酸丝状杆菌(F.succinogenes)的数量进行定量分析。结果表明:与对照相比,FOS显著降低了瘤胃菌群的多样性(P<0.05),而IMO及混合低聚糖对瘤胃菌群的多样性无显著影响(P>0.05);2种低聚糖均显著降低了DGGE凝胶上的条带数(P<0.05),而混合低聚糖处理后DGGE凝胶上的条带数则无显著变化(P>0.05);FOS提高了羔羊瘤胃总菌(P<0.05)、R.flavefaciens(P<0.05)和F.succinogenes(P>0.05)的数量,而IMO和混合低聚糖显著降低了F.succinogenes的数量(P<0.05)。由此得出:低聚糖能够改变断奶羔羊瘤胃菌群结构,FOS可提高瘤胃总菌及R.flavefaciens和F.succinogenes的数量。

The experiment was conducted to study the effects of oligosaccharides on rumen microflora of weanling lambs.Forty F2 generation weanling lambs of Dorset with similar age and body weight were randomly allotted into 4 groups with 10 replicates per group and 1 lamb per replicate.The 4 groups were control group （basal diet）,isomalto-oligosaccharide （IMO） group （basal diet＋0.3% IMO）,fructo-oligosaccharide （FOS） group （basal diet＋0.3% FOS） and mixed oligosaccharides group （basal diet＋0.3% IMO＋0.3% FOS）,respectively.The experiment lasted for 42 d （7 d for adaptation and 35 d for test）.Diversity of rumen microflora was determined based on V6 to V8 variable regions of bacteria 16S rRNA by using denaturing gradient gel electrophoresis （DGGE） technique.The number of total bacteria,R.flavefaciens and F.succinogenes in the rumen was quantified by real-time quantitative PCR.The results showed as follows：compared with the control,the FOS significantly decreased the diversity of rumen microflora （P〈0.05）,but the diversity of rumen microflora was not affected by the IMO and mixed oligosaccharides （P〉0.05）;the FOS and IMO significantly decreased the number of bands in DGGE gel （P〈0.05）,while the number of bands in DGGE gel was not affected by the mixed oligosaccharides （P〉0.05）.The number of total bacteria （P〈0.05）,R.flavefaciens （P〈0.05） and F.succinogenes （P〉0.05） in rumen was increased by the FOS,while the number of F.succinogenes was significantly decreased by the IMO and mixed oligosaccharides （P〈0.05）.In conclusion,oligosaccharides can change the configuration of rumen microflora of weanling lambs,and the FOS can increase the number of total bacteria,R.flavefaciens and F.succinogenes in rumen.