Madaro Angelico, Sandlund Nina, Oldham Tina M W, Folkedal Ole, Nilsson Jonatan, Stien Lars Helge
Research Group Animal Welfare, Institute of Marine Research, Bergen, Norway.
Research Group Pathogen Transmission and Disease, Institute of Marine Research, Bergen, Norway.
J Fish Dis. 2025 Sep;48(9):e14118. doi: 10.1111/jfd.14118. Epub 2025 Apr 1.
Largely unpredictable, gelatinous plankton blooms are a growing concern for the ever-expanding mariculture industry. Recently, a bloom of a colonial hydrozoan known as Apolemia sp. was detected via a citizen-science initiative, Nye.dugnadforhavet.no, in mid-Norway in July 2023. By November 2023, the bloom spanned the entire 2500 km Norwegian coast, adversely impacting the aquaculture industry nationwide. This report describes the clinical presentation and pathology on farmed Atlantic salmon (Salmo salar) caused by an unprecedented bloom of Apolemia sp. at the Austevoll station of the Institute of Marine Research in Norway. Shortly after the Apolemia sp. arrived, many fish showed impaired swimming capacity and erratic behaviour. Over the following days, several fish displayed wounds on their eyes and skin, while daily mortality in some cages exceeded 17%. Histopathological analyses on moribund fish revealed acute gill damage and secondary complications, including necrosis and bacterial infections, in addition to ongoing amoebic gill disease (AGD). Blood biomarker profiles indicated severe physiological stress and organ dysfunction. Ultimately, all affected fish on site were euthanized due to welfare concerns, as was also the case for several other Norwegian salmon farms. This underscores the necessity for enhanced monitoring and mitigation strategies to protect farmed fish from such harmful events. The events of 2023 in Norway highlight the vulnerability of aquaculture to gelatinous plankton blooms and the necessity for research and innovation to develop effective monitoring and management practices.
凝胶状浮游生物大量繁殖在很大程度上不可预测，这日益引起不断扩张的海水养殖业的关注。最近，通过公民科学倡议“Nye.dugnadforhavet.no”，在2023年7月于挪威中部检测到一种名为Apolemia sp.的群体水螅虫大量繁殖。到2023年11月，这种繁殖现象蔓延至整个2500公里的挪威海岸，对全国的水产养殖业产生了不利影响。本报告描述了挪威海洋研究所奥斯特沃尔站前所未有的Apolemia sp.大量繁殖对养殖大西洋鲑（Salmo salar）造成的临床表现和病理情况。Apolemia sp.到来后不久，许多鱼的游泳能力受损且行为异常。在接下来的几天里，几条鱼的眼睛和皮肤出现伤口，而一些网箱中的日死亡率超过17%。对濒死鱼的组织病理学分析显示，除了持续的阿米巴鳃病（AGD）外，还有急性鳃损伤和包括坏死及细菌感染在内的继发性并发症。血液生物标志物谱表明存在严重的生理应激和器官功能障碍。最终，出于福利考虑，现场所有受影响的鱼都被安乐死，其他几个挪威鲑鱼养殖场也是如此。这凸显了加强监测和缓解策略以保护养殖鱼类免受此类有害事件影响的必要性。2023年挪威发生的这些事件凸显了水产养殖业对凝胶状浮游生物大量繁殖的脆弱性，以及开展研究和创新以制定有效监测和管理措施的必要性。
