In 2018, Vagococcus salmoninarum was isolated from two lots of broodstock "coaster" brook trout (Salvelinus fontinalis) containing ~1,500 fish at the Iron River National Fish Hatchery, at which time it was identified as the causative agent of a chronic coldwater streptococcosis epizootic. Clinical signs included exophthalmia, lethargy, erratic swimming and loss of equilibrium. Female fish experienced disproportionately higher morbidity and mortality than male co-inhabitants, and routinely retained eggs following spawning. The most consistent gross clinical sign was heart pallor and turbid pericardial effusion. An attempted treatment using florfenicol was ineffective at halting the epizootic, which spanned more than a year and resulted in >50% mortality before remaining fish were culled. As there is no previous documentation of V. salmoninarum at this hatchery or in this species, it is still unclear what circumstances led to this epizootic. The inability to treat this chronic disease led to the loss of valuable broodstock, hampering ongoing fishery conservation efforts in the Great Lakes Basin.

中文翻译：

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Vagococcus salinainarum IA在美国威斯康辛州亲虾溪鳟鱼（Salvelinus fontinalis）中发生的慢性冷水链球菌病。

在2018年，在铁河国家鱼类孵化场从两批含有约1,500条鱼的亲鱼“沿海”溪鳟（Salvelinus fontinalis）中分离到了鲑鱼小球菌，当时它被确认为慢性冷水链球菌流行的致病因子。临床体征包括眼球突出，嗜睡，游泳不规律和失去平衡。雌性鱼类的发病率和死亡率比雄性同居鱼类高得多，并且在产卵后通常保留卵。最一致的总体临床体征是心脏苍白和浑浊的心包积液。尝试使用氟苯尼考的​​治疗无法有效停止流行病，这种流行病持续了一年多，导致在剩余鱼被扑杀之前死亡率超过50％。由于没有V的先前文档。在该孵化场或该物种中的沙门氏菌，目前尚不清楚什么情况导致这种流行。无法治疗这种慢性病导致宝贵的亲本丧失，阻碍了大湖盆地正在进行的渔业保护工作。