Improved upper thermal tolerance in rainbow trout

水产养殖被认为是一种日益增长的就业来源，并为工业选择有限的社区提供了改善社会和经济的可能性。安大略省是供人类食用的彩虹鲑鱼的主要加拿大生产国。幼鲑鱼(称为育种鱼)是由成年育种者(亲鱼)培育出来的，在陆上孵化场饲养几个月。然后它们被运送到乔治亚湾和休伦湖北海峡的笼子里，在那里夏天种植和收获。尽管市场需求和消费者对安大略省鲑鱼的接受度非常高，但养殖鱼产品的进口主导了市场。安大略省种苗的主要生产商(安大略省新邓迪的Lyndon Fish孵化公司)无法满足在笼子里种植种苗的需求。加拿大鲑鱼水产养殖业的发展受到夏季不断上升的温度的限制，因为鱼被暴露在笼子里。水温升高导致压力，结果鱼四周或更长时间不取食和生长--鱼片产量可能减少高达25%。我们建议的研究将使用两种相互关联的策略来加快虹鲑鱼的开发和供应，以适合在更高的水温下养殖。首先，我们将确定与提高对热应激的耐受性有关的遗传标记。这将有助于林登虹鲑鱼亲鱼的遗传改良，从而提高安大略省养殖业的生产率。其次，我们将探索一种新的方法，在这种方法中，幼鱼预先适应温和的热应激，并测试它们在长大后是否能够抵抗压力。该项目涉及来自两所加拿大大学和两个支持组织的团体。这一协调一致的努力是应用先进生物技术提高加拿大资源型产业之一--水产养殖业能力的一个例子。

Aquaculture is recognized as a growing source of employment and offers the possibility for social and economic improvements in communities with limited industrial alternatives. Ontario is the major Canadian producer of rainbow trout for human consumption. Young trout (called seedstock) are produced from adult breeders (broodstock) and reared for several months in land-based hatcheries. They are then transported to cages in Georgian Bay and the North Channel of Lake Huron where they are grown over the summer and harvested. Even though market demand and consumer acceptability for Ontario trout is very strong, imports of farmed fish products dominate the marketplace. The major producer of seedstock in Ontario (Lyndon Fish Hatcheries Inc., New Dundee, Ontario) is unable to meet the demand for seedstock to be grown in cages. The development of Canadian trout aquaculture is limited by the ever increasing summer temperatures that the fish are being exposed to in the cages. Increased water temperatures lead to stress and as a result the fish do not feed and grow for four weeks or more - fillet yield can be reduced by up to 25%. Our proposed research will use two inter-related strategies expedite the development and availability of rainbow trout that are suited to culture at higher water temperatures. First, we will identify genetic markers that are associated with increased tolerance to thermal stress. This will facilitate the genetic improvement of the Lyndon rainbow trout broodstock and thus increase productivity of the Ontario industry. Second, we will explore a novel approach where young fish are pre-conditioned to mild thermal stress and test whether they are able to resist stress when they are older. This project involves groups from two Canadian universities and two supporting organizations. This concerted effort is an example of an advanced biotechnology being applied to enhance the capability of one of Canada's resource based industries, namely aquaculture.