Assessing heritable variation in biological control of the salmon louse by two species of cleaner fish and co-operative behaviour by their client, Atlantic salmon

评估两种清洁鱼对鲑鱼虱子的生物控制的遗传变异及其客户大西洋鲑鱼的合作行为

• 批准号: 506655-2017
• 负责人: Boulding, Elizabeth
• 金额: $ 11.45万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Strategic Projects - Group
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=645982
• 关键词: Assessing; heritable; variation; biological; control

Aquaculture now produces all the Atlantic salmon consumed by Canadians as well as a significant amount for export. The salmon louse is a marine parasitic species of copepod that has a direct impact on farm income through inventory losses caused by skin and gill damage which can also increase disease risks. Levels of sea lice infestation were historically controlled using husbandry practices including area management and lower stocking densities. A limited number of chemical therapeutants have been authorized for use but sole reliance on these parasiticides can lead to sea lice resistance. The industry has now adopted an Integrated Pest Management approach to sea lice management, which uses several alternate treatment options. In Europe, cleaner fishes such as the lumpfish and European wrasses are introduced into sea cages to eat the lice off the Atlantic salmon. In eastern Canada, the lumpfish and a North American wrasse, the cunner, have been shown**to significantly reduce adult lice densities on salmon living in marine sea cages. Further some families of lumpfish are more effective lice cleaners than others suggesting lice cleaning propensity is heritable. It is unknown whether co-operative behaviour by salmon (e.g., remaining stationary) to facilitate lice cleaning ever occurs in sea cages, and if so whether the behaviour is heritable. Genotyping Atlantic salmon with high density SNP (Single Nucleotide Polymorphisms) chips has revealed SNPs associated with lower lice counts in the absence of cleaner fish. Our proposal has the following objectives: 1) determine the best size-class of cunners to use to clean Atlantic salmon in commercial sea cages; 2) determine the stock structure and examine variation in lice-cleaning performance among cunners and among lumpfish from different stocks; 3) assess heritable variation in lice eating behaviour among families of cunners and of lumpfish; 4) Conduct lice challenges with and without the lice cleaner fish present to see if there is a change in the ranking of salmon families with respect to lice counts with and without the biological control agent present. Our work will reduce the economic costs of sea lice control by the Canadian Atlantic salmon industry and increase its sustainability.

水产养殖业现在生产加拿大人消费的所有大西洋鲑鱼，以及大量用于出口的三文鱼。鲑鱼虱是一种海洋桡足类寄生物种，通过皮肤和鳃受损造成的库存损失直接影响农场的收入，这也会增加疾病风险。海虱侵扰程度历来是通过包括区域管理和较低放牧密度在内的畜牧业做法来控制的。已批准使用数量有限的化学治疗药物，但单纯依赖这些寄生虫剂可能会导致对海虱的抗药性。该行业现已采用病虫害综合管理方法来管理海虱，该方法使用了几种替代治疗方案。在欧洲，更清洁的鱼类，如团头鱼和欧洲乌鱼被引入海笼中，以吃掉大西洋鲑鱼上的虱子。在加拿大东部，斑点金枪鱼和北美狡猾的鳄鱼已经被证明可以显著减少生活在海洋网箱中的鲑鱼的成体虱子密度。此外，一些团头鱼家族比其他家族更有效地清除虱子，这表明虱子清洁倾向是可以遗传的。目前尚不清楚在海水网箱中是否出现过鲑鱼的合作行为(例如，保持静止)以帮助清理虱子，如果是的话，这种行为是否可遗传。用高密度单核苷酸多态(SNP)芯片对大西洋鲑鱼进行基因分型发现，在没有更清洁的鱼的情况下，SNP与较低的虱子数量有关。我们的建议有以下目标：1)确定商业网箱中用于清洗大西洋鲑鱼的最佳Cunner大小类别；2)确定种群结构，并检查Cunner和不同种群的团头鱼之间的虱子清除性能差异；3)评估Cunner家族和团头鱼家庭之间吸虱行为的遗传差异；4)在有和没有有虱子清洁剂的情况下进行虱子挑战，看看在有和没有有生防剂的情况下，三文鱼家族的虱子数量排名是否发生了变化。我们的工作将降低加拿大大西洋鲑鱼产业控制海虱的经济成本，并增加其可持续性。