Risk factors for escalating saprolegniosis outbreaks in salmon farms (RIFE-SOS)

鱼类疾病对水产养殖业和全球粮食安全构成巨大威胁。水产养殖中一些最重要的致病生物是卵菌或水霉菌的一部分，特别是寄生藻、斜斑藻和南斑藻正在造成严重的鱼类损失。总的来说，在大多数鲑鱼孵化场和淡水场所，这些真菌样生物每年至少造成10%的死亡率。因此，Saprolegnia是大西洋鲑鱼最重要的病原体之一。不幸的是，在过去几年中，苏格兰农场中腐殖质菌病爆发的发生率显著增加。事实上，由于腐殖质增生，一些部位的损失非常大。而其他农场基本上没有疾病。一些农场受到严重影响，而另一些农场似乎避免了疾病爆发，其福利标准和畜牧业管理做法明显相同，其原因目前完全不清楚，并构成目前应用的主要理由。我们的假设是，几个风险因素（与鱼类、病原体和环境有关）在抑制鱼类对坏疽的免疫力方面发挥协同作用，从而导致坏疽病的爆发。因此，我们提出了一个协调一致的全行业、行业主导和行业支持的研究方案，以发现、绘制、建模和理解导致腐臭症爆发的主要驱动因素和风险因素。将建立一个“大数据”资源，用统计方法对其进行审查，以确定坏血病爆发的主要风险因素和条件。毫无疑问，确定主要风险因素或风险因素的组合将大大有助于鲑鱼水产养殖业预先预防未来的任何暴发，并将导致对鲑鱼病管理采取综合办法，从而提高福利标准，改善鱼类健康，减少损失并降低生产和治疗费用。

Fish diseases are a huge threat for the aquaculture industry and for global food security. Some of the most important disease-causing organisms in aquaculture are part of the oomycetes or watermoulds, in particular Saprolegnia parasitica, Saprolegnia diclina and Saprolegnia australis are causing serious fish losses. Collectively, these fungal-like organisms are responsible for at least 10% annual mortalities in most salmon hatcheries and freshwater sites. Consequently, Saprolegnia ranks among the most important pathogens of Atlantic salmon.Unfortunately, over the last few years the incidences of saprolegniosis outbreaks in Scottish farms have significantly increased. Indeed, some sites have had very high losses due to saprolegniosis. Whereas other farms have remained largely disease free. The reasons as to why some farms are badly affected and others seem to avoid disease outbreaks, with apparent identical welfare standards and husbandry management practises, are at present completely unclear and form the main rational for the current application.Our hypothesis is that several risk factors (pertaining to fish, pathogens and the environment) are playing a synergistic role in suppressing immunity in fish towards Saprolegnia, which lead to outbreaks of saprolegniosis. Therefore, we propose a concerted industry-wide, industry-led and industry-supported research programme to discover, map, model and understand the main drivers, risk factors, that allow saprolegniosis outbreaks. A "big data" resource will be created that will be scrutinised with statistical methods to identify the main risk factors and conditions for outbreaks of saprolegniosis. Undoubtedly, identifying the main, or a combination of, risk factors will greatly aid the salmon aquaculture industry to pre-empt any future outbreaks and would lead to an integrated approach to saprolegniosis management, which would result in increased welfare standards, improved fish health, fewer losses and a reduction in production and treatment costs.