Environmental and genetic factors affecting physiological performance in salmonids

影响鲑鱼生理性能的环境和遗传因素

• 批准号: 227873-2007
• 负责人: Shrimpton, JamesMark
• 金额: $ 2.08万
• 依托单位: University of Northern British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=393678
• 关键词: Environmental; genetic; factors; affecting; physiological

Pacific salmon must undergo a remarkable transformation to maintain internal equilibrium as they migrate between fresh- and seawater. The change from stream dwelling parr to migratory smolt is characterized by a complex series of developmental events that prepare fish for entry into seawater. Hormonal changes in response to springtime increases in daylight and temperature stimulate the physiological phenomenon known as smolting. We know considerably less about the physiological changes that occur in maturing adult salmon as they migrate back to freshwater. Among and within species, the mechanisms for maintaining internal salt balance are similar. There is considerable variation, however, in the age, size and timing of migration between seawater and freshwater. This variability in life history traits provides a mechanism for fish to exploit new habitats or respond to rapid changes in their environment that occur naturally or due to human disturbance. The role genetics plays in the physiological adaptations that allow salmon to exploit new, or survive in disturbed habitats, is not well understood. The objective of the proposed research is to compare physiological performance of salmon from divergent geographic regions and examine their growth, development and survival under environmental conditions to which they are naturally adapted. In addition, changes in physical factors will be used to assess performance among different populations. A further approach for these investigations will be to alter the genotype through the creation of families from different populations of salmon and by modifying ploidy. The investigation of environmental, developmental and genetic bases of phenotypic expression is a novel approach to understanding the mechanisms controlling ion balance in salmon. The proposed work will provide insight into the ability of salmonids that differ genetically to respond to changes in the environment. In addition, there are a number of practical applications to this work. Understanding the interactions between genetic and environmental factors will benefit selection of strains for re-establishment of wild runs and for aquaculture production.

太平洋鲑鱼在淡水和海水之间迁徙时，必须经历一次显着的转变，以保持内部平衡。从溪流栖息到迁徙鱼类的变化的特点是发生了一系列复杂的发育事件，为鱼类进入海水做好准备。随着春季日光和温度的增加，荷尔蒙的变化会刺激一种被称为阴燃的生理现象。我们对成熟的成年鲑鱼在迁徙回淡水时发生的生理变化知之甚少。在物种之间和物种内部，维持内部盐分平衡的机制是相似的。然而，海水和淡水之间的迁移在年龄、大小和时间上有相当大的差异。生活史特征的这种变异性为鱼类开发新的栖息地或对自然或人类干扰导致的环境快速变化做出反应提供了一种机制。在允许鲑鱼开发新的或在受干扰的栖息地生存的生理适应中，遗传学所起的作用还不是很清楚。拟议研究的目的是比较来自不同地理区域的鲑鱼的生理表现，并检查它们在自然适应的环境条件下的生长、发育和存活。此外，身体因素的变化将被用来评估不同人群的表现。这些调查的另一种方法将是通过从不同种群的鲑鱼创建家系和通过修改倍性来改变基因型。研究鲑鱼表型表达的环境、发育和遗传基础是理解鲑鱼离子平衡控制机制的新途径。这项拟议的工作将提供对遗传上不同的鲑鱼对环境变化做出反应的能力的洞察。此外，这项工作还有许多实际应用。了解遗传和环境因素之间的相互作用将有助于选择菌株以重建野生种群和进行水产养殖生产。