For half a decade, the Atlantic salmon in the Baltic Sea has been facing severe health issues. Clinical signs like haemorrhage, erosions and ulcerative/necrotic skin conditions in returning adults have been reported from different Swedish rivers. These primary disease signs precede a secondary, terminal fungal infection. As initial investigations of the disease did not provide conclusive answers regarding the pathogenesis, this study was initiated to gain insight into a possible link between this so‐called Red Skin Disease and anthropogenic influences. Therefore, returning salmon were caught in rivers along the Swedish coast and different tissues were sampled. The focus was put on the measurements of a battery of biomarkers as well as biochemical and haematological parameters, which were analysed using multivariate statistics. The main findings were a severe osmotic haemodilution, an immune response and an alteration of the carbohydrate metabolism in diseased fish. Furthermore, oxidative stress does not seem to be a likely factor in the pathogenesis. Concluding, certain changes in physiological parameters were shown to be indicative for the disease patterns, while others were ruled out as significant factors. Thus, this study contributes to the understanding of the Red Skin Disease and may act as a hypothesis generator for future studies.

中文翻译：

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对波罗的海正在出现的红色皮肤病影响的大西洋鲑（Salmo salar L.）进行的多生物标记研究

六年来，波罗的海的大西洋鲑鱼一直面临严重的健康问题。从瑞典的不同河流中报告了返回的成年人的出血，糜烂和溃疡/坏死性皮肤病等临床症状。这些原发疾病征兆先于继发性终末真菌感染。由于对该疾病的初步研究并未提供有关发病机理的结论性答案，因此启动本研究是为了深入了解这种所谓的“红色皮肤病”与人为影响之间的可能联系。因此，返回的鲑鱼被捕获在瑞典沿海的河流中，并取样了不同的组织。重点放在一系列生物标志物的测量以及生化和血液学参数上，这些数据使用多元统计数据进行了分析。主要发现是严重的渗透性血液稀释，免疫反应和患病鱼类碳水化合物代谢的改变。此外，氧化应激似乎不是发病机理中的可能因素。结论是，生理参数的某些变化表明是疾病模式的指示，而其他因素则被排除为重要因素。因此，这项研究有助于理解红色皮肤病，并且可以作为未来研究的假设产生者。排除了其他因素作为重要因素。因此，这项研究有助于理解红色皮肤病，并且可以作为未来研究的假设产生者。排除了其他因素作为重要因素。因此，这项研究有助于理解红色皮肤病，并且可以作为未来研究的假设产生者。