House M L, Hedrick R P, Winton J R, Fryer J L
a Department of Microbiology , Oregon State University , Corvallis , Oregon , 97331 , USA.
b Department of Medicine and Epidemiology , School of Veterinary Medicine, University of California , Davis , California , 95616 , USA.
J Aquat Anim Health. 2006 Dec;18(4):252-6. doi: 10.1577/H05-056.1.
The virulence of the WSB-98 isolate of Piscirickettsia salmonis from white seabass Atractoscion nobilis was compared with that of the American Type Culture Collection type strain LF-89, which was originally isolated from coho salmon Oncorhynchus kisutch in Chile. In controlled laboratory challenges of juvenile coho salmon, the isolate from white seabass exhibited virulence that was equal to or greater than that of LF-89. The cumulative percent mortality (CPM) was similar between groups of coho salmon receiving an intraperitoneal injection of WSB-98 at 10(4.5) tissue culture infectious dose with 50% endpoint (TCID50)/fish (CPM = 98%) or an injection of LF-89 at 10(4.8) TCID50/fish (CPM = 95%). The mean day to death of 9.3 d for WSB-98 and 18.6 d for LF-89, however, differed significantly (P < 0.0001) between the two isolates. The virulence of an isolate of P. salmonis from white seabass for a salmonid species is consistent with the hypothesis that nonsalmonids can serve as natural marine hosts for the bacterium and potential sources for infection of salmonids.
将来自白鲈（Atractoscion nobilis）的鲑鱼立克次氏体（Piscirickettsia salmonis）WSB - 98分离株的毒力与美国典型培养物保藏中心的模式菌株LF - 89进行了比较，LF - 89最初是从智利银大麻哈鱼（Oncorhynchus kisutch）中分离得到的。在对银大麻哈鱼幼鱼进行的受控实验室攻毒试验中，来自白鲈的分离株所表现出的毒力等于或大于LF - 89。接受腹腔注射10(4.5)组织培养感染剂量的50%终点（TCID50）/鱼的WSB - 98的银大麻哈鱼组与接受注射10(4.8) TCID50/鱼的LF - 89的银大麻哈鱼组之间的累积死亡率（CPM）相似（CPM = 98%对CPM = 95%）。然而，WSB - 98的平均死亡天数为9.3天，LF - 89为18.6天，这两种分离株之间存在显著差异（P < 0.0001）。来自白鲈的鲑鱼立克次氏体分离株对鲑科物种的毒力与非鲑科鱼类可作为该细菌的天然海洋宿主以及鲑科鱼类感染的潜在来源这一假设相一致。
