The paper was conducted with the objective of identification of a lactic acid-producing strain of Ba-cillus sp. BLZ01 and its influence on the intestinal flora of the broiler. Combining the morphological, physio-chemical properties with 16S rRNA sequencing analysis, strain of Bacillus sp. BLZ01 was identified. Twenty 7-day-old broilers were randomly divided into 2 groups ( each group included 10 broilers) . The control group was fed the basal diet. The experimental group was fed the basal diet supplemented with 0. 05 g/kg of the BLZ01 probiotics. At the age of 42 days, the ileum and cecum microflora diversity of broilers were analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis ( PCR-DGGE) . The results showed as fol-lows:1) strain of BLZ01 was identified as Bacillus megaterium which could produce levolactic acid. 2) The number of PCR-DGGE bands and concentration of the ileum and cecum microflora in broilers treated with Ba-cillus megaterium BLZ01 was siginificantly increased compared with that of control group. 3) Lactobacillus sp. and uncultured bacteria were mainly appeared in the sequences of DNA recovered from single band in DGGE fingerprints by identified. The results indicated that strain of Bacillus BLZ01 is Bacillus megaterium which can produce levolactic acid;the abundance and population density of intestinal microflora in broiler treated with Ba-cillus megaterium BLZ01 are increased.%本试验旨在对一株产乳酸芽孢杆菌进行菌种的鉴定,并研究其对肉鸡肠道菌群的影响. 采用传统的形态学、生理生化反应与16S rRNA序列分析相结合的方法对菌株BLZ01进行鉴定. 选取20羽7日龄肉鸡,随机分成2组(每组10羽) ,对照组饲喂基础饲粮,试验组饲喂添加0.05 g/kg菌株BLZ01的试验饲粮. 饲喂至42日龄时,采用聚合酶链式反应-变性梯度电泳技术( PCR-DGGE)技术分析肉鸡回肠、盲肠肠道菌群的多样性. 结果表明:1)菌株BLZ01确定为产L-乳酸的巨大芽孢杆菌;2)肉鸡饲喂菌株BLZ01后,回肠、盲肠的条带数均增多,浓度发生了明显的变化;3)回收的条带以未培养的细菌为主,已培养出的细菌是以乳杆菌属为主. 结果表明,芽孢杆菌BLZ01为一株产L-乳酸的巨大芽孢杆菌;肉鸡饲喂该菌后可以提高其肠道菌群的多样性和种群密度.
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