Characterization of 2N and 3N freshwater rainbow trout strains for better lake stocking strategies

加拿大的休渔业直接通过鱼类养殖和许可证销售，间接通过促进旅游业，提供了超过49亿美元的经济活动。 加拿大大多数受欢迎的捕鱼湖每年都有各种鱼类，特别是虹鳟鱼，以减轻密集的捕鱼活动对自然野生鱼类种群的影响。 然而，大多数这些放养计划，特别是在不列颠哥伦比亚省经验非常高的放养死亡率，特别是在三倍体鱼。 三倍体是创造非繁殖鱼类的一种手段，其好处是消除了放养鱼类和野生种群之间的遗传物质交换。 仅在不列颠哥伦比亚省，不列颠哥伦比亚省淡水渔业协会（FFSBC）每年就在900多个湖泊中放养超过500万条鳟鱼（约250万条三倍体），在某些情况下，70%的鱼类在放养后几天或几周内死亡。这些高死亡率的确切原因尚不清楚，但有证据表明，湖泊化学和放养/野生鱼类竞争的变化可能都是造成这种高死亡率的重要因素。 FFSBC可以获得许多不同类型（称为品系）的鳟鱼用于放养计划，但这些不同品系的整体性能和竞争力或在不同环境条件下创造三倍体对生存和性能的影响尚不清楚。 这项赠款将描述各种鳟鱼品系的性能和环境耐受性，并研究品系之间的选择性育种对二倍体和三倍体鳟鱼总体性能的影响。 这项研究合作的目标是努力了解为什么三倍体鱼在自然环境中的表现不如二倍体鱼。 这种伙伴关系的长期目标是开发一种具有上级性能和低死亡率的三倍体鱼，每年可以为FFSBC节省180多万美元，并有助于振兴不列颠哥伦比亚省和加拿大的休闲渔业。

Recreational fishing in Canada provides more than 4.9 billion dollars in economic activity both directly through fish culture and license sales and indirectly through the promotion of tourism. Most of Canada's popular fishing lakes are stocked annually with various species of fish, particularly rainbow trout, from hatcheries to mitigate the impacts of intense fishing activity on natural, wild fish populations. However, most of these stocking programs, particularly in British Columbia experience very high stocking mortality rates, particularly in triploid fish. Triploidy is a means of creating non-reproductive fish, which have the benefit of eliminating the exchange of genetic material between stocked fish and wild populations. In British Columbia alone, the Freshwater Fisheries Society of BC (FFSBC) stocks over 5 million trout a year (~2.5 million as triploids) into > 900 lakes and in some cases up to 70% of the fish introduced into a lake die within days or weeks of stocking. The precise reasons for these high death rates are not known, but there is evidence that variation in lake chemistry and stocked/wild fish competition may both be important contributors to this high mortality. FFSBC has access to many different types (called strains) of trout for stocking programs, but the overall performance and competitiveness of these different strains or the effects of creating triploids on survival and performance under different environmental conditions are not known. This grant will characterize the performance and environmental tolerance of various strains of trout and examine the effects of selective breeding between strains on the overall performance of diploid and triploid trout. The goal of this research partnership is to work toward understanding why triploid fish do not perform well in natural environments compared with their diploid counterparts. The long-term goal of this partnership is to develop a triploid fish with superior performance and low mortality rates could save the FFSBC more that 1.8 million dollars a year and help revitalize recreational fishing in British Columbia and Canada.