斑点叉尾鲖源杀鲑气单胞菌无色亚种分离鉴定及药敏特性

ISOLATION AND IDENTIFICATION OF AEROMONAS SALMONICIDA SUBSP. ACHROMOGENES FROM ICTALUNES PUNCTATUS AND ITS ANTIMICROBIAL SUSCEPTIBILITY

摘要: 研究从患溃疡症斑点叉尾鲙中分离到一株致病性菌株ry01, 生理生化鉴定和16S rDNA基因序列分析表明ry01株为鲑气单胞菌无色亚种(Aeromonas salmonicida subsp. achromogenes)。人工感染该菌后发病鱼表现为与自然发病类似症状, 且从组织中再分离的细菌特性与原感染菌相同。腹腔注射后该菌株对斑点叉尾鲙的半数致死量为4.17×10⁶ CFU/mL。菌株ry01对强力霉素及左氧氟沙星等高度敏感, 为斑点叉尾鲙该病防控提供了理论依据。

Abstract: The isolated bacterial strain ry01 from Ictalunes punctatus with ulcer disease was identified as Aeromonas salmonicida subsp. achromogenes by analyzing biochemical reactions and 16S rDNA gene sequence. The ry01-injected fish showed similar morphological and biochemical characteristics to those from naturally infected fish, supporting that Aeromonas salmonicida subsp. achromogenes was the pathogen to Ictalunes punctatus. The LD₅₀was 4.17×10⁶ CFU/mL according to the Reed-Muench method. The isolated bacterial strain ry01 was highly sensitive to doxycycline and levofloxacin. This study provides theoretical basis for the prevention and control the disease of Ictalunes punctatus.