选用 GYK_1、Q_1、B_7三株毒力不同的嗜水气单胞菌(Aeromonas hydrophila)对剑尾鱼(Xi-phophorus helleri)进行了人工感染试验。结果显示 GYK_1、Q_1、B_7三株菌之间毒力存在明显差异:以GYK_1毒力最强,Q_1毒力次之,B_7毒力最弱。感染发病鱼呈现接种部位溃疡、腹水、败血等明显症状。病理组织学变化以全身溶血性贫血和广泛的组织细胞变性、坏死为主。 Three artificial virulent strains, Aeromonas hydrophila GYK_1, Q_1 and B_7, were selected to perform artificial infection test on Xi-phophorus helleri. The results showed that there were significant differences in the virulence of GYK_1, Q_1 and B_7 among the three strains. The virulence of GYK_1 was the strongest, that of Q_1 was the second, and that of B_7 was the weakest. Infected fish showed vaccination site ulcers, ascites, sepsis and other obvious symptoms. Histopathological changes to systemic hemolytic anemia and a wide range of tissue degeneration, necrosis.