Detection of tenacibaculum sp. the cause of mouthrot in Atlantic salmon raised by Marine Harvest Canada****

加拿大海洋收获公司在不列颠哥伦比亚省可持续地养殖大西洋鲑鱼。影响幼崽的一个重要生产疾病是由腱杆菌引起的口喉病。损失主要是由于幼崽的死亡，但同样重要的是由于幼崽的生长减少。治疗受影响的鱼是昂贵的，而且经常需要重复治疗，从而产生巨大的费用。与这种疾病相关的细菌也可能对现有的抗菌剂具有耐药性。因此，除抗菌药物治疗外的其他管理策略是至关重要的。该提案将适应和创建定量聚合酶链反应（qPCR）测定方法来定量负责的细菌。了解这种生物体在鱼、环境和水中的藏身之处，以及在爆发之前、期间和之后何时出现高细菌负荷，是更好地管理爆发所需的关键信息。这些检测还可用于评估抗菌治疗的疗效，并了解为什么它们往往不成功。这些检测将有助于改善MHC监测点的口腔主动管理，并应允许除抗菌治疗外的其他选择或减少抗菌使用的需要。**

Marine Harvest Canada sustainably raises Atlantic salmon in British Columbia. An important production disease affecting smolts in netpens is mouthrot caused by Tenacibaculum sp. Losses occur due to mortality but as importantly due to reduced growth. Treatment of affected fish is expensive and often has to be repeated incurring significant costs. The bacteria associated with this disease can also be resistant to the available antimicrobial agents. Management strategies other than antimicrobial therapy are therefore of critical need. This proposal will adapt and create quantitative polymerase chain reaction (qPCR) assays for quantification of the responsible bacteria. Understanding where the organism is harboured in the fish, environment and water and knowing when high bacterial loads are present before, during and after an outbreak are key information needed to better manage outbreaks. The assays can also be used to evaluate the efficacy of antimicrobial treatments and understand why they are often not successful. These assays will allow improvements to proactive management of mouthrot at MHC netpen sites and should allow options other than antimicrobial therapy or that reduce the need for antimicrobial use. **