论文部分内容阅读
用常规方法从患典型白底板病黄沙鳖的心脏、肝脏等处进行细菌的接种分离,通过人工感染确定分离菌株的致病性,API 20NE、16S rRNA基因序列分析进行病原菌鉴定和确定其系统发育地位,K-B纸片扩散法进行药敏试验,PCR检测病原菌的6种毒力基因。试验结果,共分离到13株病原菌,其中嗜水气单胞菌9株,温和气单胞菌4株。在9株嗜水气单胞菌中,有5株与Aeromonas hydrophila ATCC 7966菌株亲源关系最近,4株与Aeromonas hydrophila北京株QDC01的亲源关系最近;而4株温和气单胞菌与Aeromonas sobria ATCC43979的亲源关系最近。药敏试验结果,仅头孢哌酮对13株病原菌都高度敏感,来源于不同养殖区域的病原菌药敏结果相差较大。6种毒力基因的阳性率,Aer、Act和ahp均为100%,hly和Alt为92.31%,ahal为76.92%;毒力基因型共有4种,嗜水气单胞菌主要为hly+Aer+Alt+Act+ahal+ahp+基因型,而温和气单胞菌主要为hly+Aer+Alt-Act+ahal+ahp+基因型,同时携带hly基因的菌株其致病力更强。
Pathogenicity of the isolated strains was determined by artificial infection and the pathogenic bacteria were identified by API 20NE and 16S rRNA gene sequence analysis and their system was identified by routine methods from the heart, Development status, KB disk diffusion method for susceptibility testing, PCR detection of pathogenic bacteria 6 virulence genes. Test results, a total of 13 strains of pathogens were isolated, of which 9 strains of Aeromonas hydrophila, 4 strains of Aeromonas sobria. Among 9 strains of Aeromonas hydrophila, 5 strains had the closest relationship with Aeromonas hydrophila ATCC 7966, 4 strains had the closest relationship with Aeromonas hydrophila Beijing strain QDC01, while 4 strains with Aeromonas sobria The closest relatives of ATCC43979. Susceptibility test results, only cefoperazone highly sensitive to 13 pathogens, pathogens from different culture areas of susceptibility results vary greatly. The positive rates of 6 virulence genes were 100% for Aer, Act and ahp, 92.31% for hly and Alt, 76.92% for ahal, 4 for virulence genotypes, and the majority of Aeromonas hydrophila strains were hly + Aer + Alt + Act + ahal + ahp + genotypes, whereas Aeromonas sobria was mainly hly + Aer + Alt-Act + ahal + ahp + genotypes, while strains harboring hly genes were more virulent.