摘要
为了确定2013年9月至2013年11月江西省某规模猪场仔猪疑似发生猪链球菌病的病原菌及其毒力特性,本试验将病猪剖杀,采取脑脊液和关节液在血平板上划线进行细菌分离培养,将分离到的菌株进行生化试验、16SrDNA序列分析及基因血清分型鉴定,进一步对其进行毒力基因(gdh、orf2、fbps、sly、epf、mrp)检测和药敏性测定。结果显示,分离菌株在血平板上形成灰色"半透明"边缘整齐的有草绿色狭窄溶血环的光滑型圆形细小菌落,镜检呈散在排列的革兰氏阳性短链球菌,结合生化试验、16SrDNA序列分析及基因血清型分型,确定其病原为2型猪链球菌,命名为JMS2。毒力因子基因检测结果显示,JMS2主要毒力因子分布为gdh+/orf2+/fbps+/sly-/epf-/mrp-,预示JMS2可能不是强毒力菌株。药敏试验结果显示,JMS2对β-内酰胺类抗生素如青霉素、阿莫西林等敏感,但对阿奇霉素、复方新诺明等细菌蛋白质合成抑制剂类抗生素耐药。本研究对临床防控猪链球菌病具有参考意义。
In order to determine the pathogen and its virulence characteristics of a suspected case of piglets streptococcosis in a pig farms in Jiangxi province during September to November of 2013 ,a strain was isolated from the joint fluid and cerebrospinal fluid of one diseased piglet. The isolated strain was identified by culture characteristics, biochemical test, 16S rDNA sequence anal- ysis,serotype PCR test and further studied the presence of the following virulence genes:Gluta- mate dehydrogenase (gdh),virulent-assocciated sequence (orf2),fibronectin-binding proteins (fb- ps), suilysin (sly), extracellular protein factor (epO, muramidase-released protein (mrp) and anti- biotic sensitivity tests. The isolated strain was identified as Streptococcus suis serotype 2 by cul- ture characteristics,biochemical test, 16S rDNA sequence analysis and serotype PCR test,and it was named as JMS2. Detection results of virulence gene showed that the distribution of main vir- ulence genes of JMS2 were gdh^+/orf2^+/fbps^+/sly^-/epf^-/mrp^- , suggesting that the strain may- be not likely to be high virulence. Drug sensitivity tests showed that the JMS2 was susceptibility to β-1actams such as penicillin,amoxicillin, but resistant to azithromycin, SMZ-TMP, and so on. The result was significant for the clinical prevention and treatment of swine streptococcosis.
出处
《中国畜牧兽医》
CAS
北大核心
2015年第7期1897-1904,共8页
China Animal Husbandry & Veterinary Medicine
基金
江西省科技支撑计划项目(20112BBF60018)
江西农业大学科学研究基金项目(CX201107)
关键词
2型猪链球菌
分离鉴定
毒力因子基因
药敏试验
Streptococcus suis serotype 2
isolation and identification
virulence gene
drug sensi-