CAJ | 학술논문

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 ATCC 43979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。
용상규방법종환전형백저판병황사별적심장、간장등처진행세균적접충분리,통과인공감염학정분리균주적치병성, API 20NE、16S rRNA기인서렬분석진행병원균감정화학정기계통발육지위, K-B지편확산법진행약민시험, PCR검측병원균적6충독력기인。시험결과,공분리도13주병원균,기중기수기단포균9주,온화기단포균4주。재9주기수기단포균중,유5주여Aeromonas hydrophila ATCC 7966균주친원관계최근,4주여Aeromonas hydrophila북경주QDC01적친원관계최근；이4주온화기단포균여Aeromonas sobria ATCC 43979적친원관계최근。약민시험결과,부두포고동대13주병원균도고도민감,래원우불동양식구역적병원균약민결과상차교대。6충독력기인적양성솔, Aer、Act화ahp균위100%, hly화Alt위92.31%, ahal위76.92%；독력기인형공유4충,기수기단포균주요위 hly＋Aer＋Alt＋Act＋ahal＋ahp＋기인형,이온화기단포균주요위hly＋Aer＋Alt-Act＋ahal＋ahp＋기인형,동시휴대hly기인적균주기치병력경강。
Pathogenetic bacteria were isolated from hearts and livers of the infected individual Truogx sinensis, cultured on conventional methods, and used as challenge to determine their infectiveness. Identities of the isolated pathogens were distinguished through API 20NE, their phylogenetic status were analyzed by 16S rRNA sequencing and their sen-sitivities to drugs were tested by K-B method. The six known virulence genes in the pathogens were detected by PCR. The results showed that, of the thirteen pathogens abtained, nine strains were Aeromonas hydrophila, and four strains were Aeromonas sobria. In phylogenetical relationship of the nine Aeromonas hydrophila, five strains were close to Aeromonas hydrophila ATCC 7966, and four strains were close to Aeromonas hydrophila QDC01, while four Aeromo-nas sobria were close to Aeromonas sobria ATCC 43979. Drug sesnsitive testes indicated that only thirteen strains were found to be highly sensitive to cefoperazone, and pathogens from different farms presented to be quite different in drug sensitivity. Virulence gene detection showed that Aer, Act and ahp was positive at 100%;hly and Alt, 92.31%;and Ahal, 76.92%. Four genotypes were found in pathogens isolated, being hly+Aer+Alt+Act+ahal+ahp+ and hly+Aer+Alt-Act+ahal+ahp+, mainly dominating in Aeromonas hydrophila and Aeromonas sobria, respectively, and strains with hly exhibited stronger pathogenicity.