抗菌肽CecropinB对鸡肠道正常微生物群的影响

Effect of CecropinB on the Intestinal Tract Normal Flora in Chickens

目的探讨重组抗菌肽CecropinB对鸡肠道正常微生物群的影响。方法 50羽健康雏鸡随机分成5组:设盐酸环丙沙星对照组,基因工程抗菌肽cecropinB高、中、低三个剂量组及空白对照组,每组10羽,均以饮水混饮的方式饲喂,分别于42、49d取盲肠、回肠内容物进行聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE),对肠道的几种优势菌的多样性进行研究,并对回肠16SrDNA进行全序列克隆、测序。结果雏鸡盲肠菌群在42日龄和49日龄之间相似性达到50%。相同日龄各组间盲肠菌群分为两大类,其中抗菌肽不同剂量组间相似性为73%及以上,而抗菌肽不同剂量组与空白对照组及抗生素对照组之间的相似性分别为61%以上和50%。各组雏鸡回肠显示两大类优势菌群,抗生素对照组为一大类,其他组别为一大类,两者间的相似性为59%;各组内样品之间相似性在92%以上,组间相似性在70%左右。对回肠内容物16SrDNA克隆、测序显示,抗菌肽高剂量组比空白对照组多出一条与厌气弯杆菌同源性为78%的条带。结论 CecropinB作为一种饲料添加剂对42与49日龄雏鸡肠道菌群无明显影响。

Objective To explore the effect of antibacterial peptide cecropinB on the intestinal tract normal flora in chickens.Methods 50 one-day-old chickens were divided randomly into experimental and control groups.2,4 and 6 mL of antibacterial peptide（ABP） cecropinB chickens in experimental groups every day and the Ciprofloxacin were administered into chickens at the same age in Ciprofloxacin control group,respectively.Traditional method and denaturing gradient gel electrophoresis（DGGE） analysis of 16S ribosomal RNA was used to analyze the difference of intestinal tact normal flora of different treats.The sequence of the ileumof 16S ribosomal RNA was cloned and sequenced.Results No significant difference were found between experimental group chickens.By cluster analysis of the dominance microbial population of the cecum and ileum,different antibacterial peptide（ABP） cecropinB were in the same species when chicken was 42 days.The dominant microbial population of the cecum analysis showed that control group and different antibacterial peptide（ABP） cecropinB were in the same species when chicken was 49 days.The similarity among them exceeded 50%,while the similarity among them exceeded 73% in the dominance microbial population of the ileum of 42 days.The similarity of antibiotic group and the other group was only 59%.The group of cecropinB（6 mL） ileum had a redundancy strap which homology was 78% with anaerobic curved bacillus.Conclusion CecropinB had not showed adverse effect on the intestinal microbial community in chickens.