The impact of climate change on infection of salmonid fish with Saprolegnia

鱼类对环境的变化非常敏感，众所周知，这种变化会导致压力增加，并会改变鱼类的免疫状态，这反过来又会导致对疾病的更高易感性。我们将研究水温和氧气变化对鲑鱼和鳟鱼感染寄生水霉和水霉的发病率和严重程度的作用。这两种病原体都会引起水原体病，这是一种鲑鱼卵和鱼类的致命疾病。水霉病通常会导致养鱼场损失10%或更多。目前，这些卵菌病原体在英国水产养殖业中排在虹鳟鱼和大西洋鲑鱼最相关病原体的前3位。将通过实验和实地研究收集关于依赖温度和氧气的病原体动态和宿主免疫反应的数据，这将为预测这些病原体因气候变化而可能产生的影响提供依据。空间分析和绘图技术将用于确定养鱼场位置、河流环境条件和病原体丰度之间的基线关系。根据对英国气候变化的预测，我们将试图预测我们研究中的病原体的影响在未来几十年可能会发生怎样的变化。该项目所产生的信息涉及BBSRC/NERC关于水产养殖：鱼类健康与疾病的联合呼吁的所有优先领域，最终将使农民能够更好地规划和设计缓解战略，这在欧盟范围内禁止在水产养殖中使用福尔马林之后尤其重要。水产养殖管理程序、生物安全和（取水或鱼类）处理方面的变化可能使养鱼户能够抵消这些鱼类病原体在应对气候变化方面的一些预期影响。该项目还将允许预测CC和水霉感染对野生鲑鱼的影响。这一信息对未来的保护战略很重要。

Fish are very sensitive to changes in their environment and it is known that such changes can lead to increased stress and can alter the immune status of the fish, which in turn can lead to higher susceptibility to diseases. We will investigate the role of water temperature and oxygen changes on the incidence and severity of salmon and trout infection with Saprolegnia parasitica and Saprolegnia diclina. Both pathogens cause saprolegniosis, which is a deadly disease of salmonid eggs and fish. Saprolegniosis can often lead to losses of 10% or more in fish farms. Currently these oomycete pathogens rank amongst the top 3 of most relevant pathogens on rainbow trout and Atlantic salmon in the aquaculture industry of the UK. Data on temperature and oxygen dependant pathogen dynamics and host immune response will be collected through experimental and field studies, which will provide a basis for predicting the likely impact of these pathogens as a result of climate change. Spatial analysis and mapping techniques will be used to identify baseline relationships between fish farm locations, environmental conditions in the river and pathogen abundance. Based on climate change predictions for the UK, we will try to predict how the impact of the pathogens in our study is likely to change over the next decades. The information generated from this project, which addresses all priority areas of the BBSRC/NERC joint call on Aquaculture: Fish Health & Disease, will ultimately allow better planning and design of mitigating strategies for farmers, which will be especially relevant after the enforcement of the EU-wide ban on the use of formalin in aquaculture. Changes in aquaculture management procedures, biosecurity and treatment (of intake water or fish) may allow fish farmers to counteract some of the expected impacts of these fish pathogens in response to climate change. The project will also allow making projections about the impact of CC and Saprolegnia infection on wild salmonid fish. This information will be important to inform future conservation strategies.