不同日粮类型对绵羊瘤胃微生物木聚糖酶基因多样性的影响  

Effects of Different Rations on Xylanase Gene Diversity of Ruminal Microorganisms in Sheep

作　　者：李晓[1,2] 杨玉霞[1] 汪艳[1] 陈勇[1] 武运[2] 

机构地区：[1]新疆农业大学动物科学学院,新疆肉乳用草食动物营养重点实验室,乌鲁木齐830052 [2]新疆农业大学食品科学与药学学院,乌鲁木齐830052

出　　处：《新疆农业大学学报》2014年第3期173-180,共8页Journal of Xinjiang Agricultural University

基　　金：新疆维吾尔自治区高技术研究发展项目(201211104);新疆维吾尔自治区科技支疆项目(201191138);新疆维吾尔自治区重点实验室开放课题(2011003)

摘　　要：选取安装有永久性瘤胃瘘管的中国美利奴绵羊4只,先后饲喂全粗料日粮和精料型日粮(精粗比3∶2),提取微生物宏基因组DNA。通过PCR产物克隆文库构建、DNA测序和序列分析以研究在不同日粮条件下,绵羊瘤胃微生物糖苷水解酶第10家族(GH10)和第11家族(GH11)木聚糖酶基因的多样性。结果表明,全粗料日粮时分别获得108和137条GH10和GH11家族木聚糖酶基因片段,精料型时分别获得145和235条GH10和GH11家族木聚糖酶基因片段,这些序列分别归属于19、20、53和26个操作分类单元(OUT)。DNA序列分析表明,GH10家族木聚糖酶基因片段与梭菌和拟杆菌来源的木聚糖酶基因有较高的相似性,GH11家族木聚糖酶基因片段与放线菌、麦角真菌来源的木聚糖酶基因有较高的相似性。饲喂全粗料日粮时,有57.9%的GH10家族序列与已知木聚糖酶基因的相似性小于90%;饲喂精料型日粮时,有65.4%的GH11家族序列与已知木聚糖酶基因的相似性小于90%。由此可见,绵羊瘤胃微生物GH10和GH11家族木聚糖酶基因序列具有丰富的多样性,并且大部分为新发现的序列。饲喂全粗料日粮时,更有利于发现瘤胃微生物GH10家族木聚糖酶新序列;饲喂精料型日粮时,更有利于发现GH11家族木聚糖酶新序列。Four Chinese Merino sheep,fitted with permanent rumen fistula were selected and fed with roughage or concentrate diets（ratio of concentrate to forage 3∶2）to study diversity of ruminal microbial glycoside hydrolase 10th family （GH10）and 11th family （GH11）xylanase gene after metagenomic DNA extraction,PCR products cloning library construction,DNA sequencing,and sequence analysis.The results show that 108 and 137 gene fragments,145 and 235 gene fragments of GH10 and GH11 family xylanase were found when whole roughage diets were fed,respectively.These sequences belong to 19,20,53 and 26 operational taxonomic units （OUT）.DNA sequence analysis showed that fragments of GH10 family xylaG nase gene fragments and Bacteroides and Clostridium have higher similarity,and fragments of GH11 family xylanase gene and that of actinomycetes and Claviceps purpurea have higher similarity .When feeding roughage diets,the similarity of 57.9% GH10 sequences and the known xylanases gene is less than 90%.When fed concentrate diets,the similarity of 65.4% GH11 sequences and the known xylanases gene is less than 90%. Thus,sheep rumen microbial GH10 and GH11 family xylanase gene sequences have rich diversity,and most of them are newly discovered sequences.It＆#39;s more conducive to discovery new GH10 and GH11 family xylanase gene fragments when sheep fed with roughage diet,respectively.

关 键 词：绵羊 瘤胃微生物 木聚糖酶基因 多样性 

分 类 号：S852.6[农业科学—基础兽医学]