Laboratory challenge of Pacific herring Clupea pallasii to Vibrio anguillarum and V. ordallii

Controlled waterborne exposures of Pacific herring (Clupea pallasii) to Vibrio anguillarum and V. ordalii failed to result in overt signs of disease or mortality from vibriosis. Cumulative mortalities among Vibrio - exposed Pacific herring (3.3 - 5.0%) were similar to those of saline-exposed negative controls (10%) and significantly less (P < 0.001) than those of Vibrio - exposed Chinook salmon (60 - 97%), a known susceptible species. Gross signs of disease did not occur on any dead or surviving Pacific herring; however, exposed Chinook salmon demonstrated classic gross signs of vibriosis. The results indicate that early reports of presumed vibriosis in Pacific herring during the 1950’s were likely misdiagnosed cases of a viral disease, possibly viral hemorrhagic septicemia or viral erythrocytic necrosis, which can cause hemorrhagic lesions superficially resembling those of vibriosis.

对太平洋鲱（Clupea pallasii）开展受控水体暴露试验，使其接触鳗弧菌（Vibrio anguillarum）与奥氏弧菌（V. ordalii），结果未观察到弧菌病的显性病症或因弧菌病导致的死亡。经弧菌暴露的太平洋鲱累积死亡率为3.3%~5.0%，与盐水暴露的阴性对照组（10%）相近，且显著低于已知易感物种——经弧菌暴露的奇努克鲑（Chinook salmon）的死亡率（60%~97%），差异具有统计学意义（P < 0.001）。所有死亡及存活的太平洋鲱均未出现显性病症；而经弧菌暴露的奇努克鲑则表现出弧菌病典型的肉眼可见病症。本研究结果表明，1950年代关于太平洋鲱疑似弧菌病的早期报道，大概率为病毒性疾病的误诊案例，此类疾病可能为病毒性出血性败血症（viral hemorrhagic septicemia）或病毒性红细胞坏死症（viral erythrocytic necrosis），这两种疾病均可引发外观上与弧菌病相似的出血性病灶。