水产养殖鱼类生长性状研究进展

生长性状是水产养殖鱼类最重要的经济性状之一,对水产养殖业的发展意义重大。通过以不同的养殖鱼类为对象,大量的研究结果表明,鱼类生长主要受环境、基因,以及基因与环境相互作用的影响,具体为:(1)环境是生长性状调控的外因,其对生长的影响一般呈现出剂量效应的规律。温度、光照、营养等主要环境因子的过量和不足均可能对鱼类生长产生不利影响,因此,寻求最优条件是制定最佳养殖环境的终极目标,人为调控多种环境因子在现代水产养殖业中具有重大的应用潜力。(2)基因是生长性状调控的内因,其对生长的影响很大程度上表现出因果效应的关系。某些基因的单碱基核苷酸多样性、基因结构变异、染色体倍性变化,以及转基因等都表现出对鱼类生长产生统计显著性的影响。鉴于生长是多基因控制的复杂数量性状,寻找主效基因并在选育中加以利用是改良生长性状的重要基础。高通量测序技术在生长相关候选基因的筛选以及辅助分子育种方面展现出强大的优势。(3)基因与环境相互作用的影响主要来自基因型对不同环境条件的适应性,具有特异性和复杂性的特点,因此目前对其量化研究非常有限。但在制定大规模商业育种计划之前,考虑基因与环境相互作用具有重要意义。综上所述,充分理解环境、基因,以及基因与环境相互作用对水产养殖鱼类生长的影响能更好地对其生长性状加以利用,从而最大限度地节约养殖成本和发挥生态效益。

Recent progress in growth trait of aquaculture fish

Fish growth is one of the most important traits in fish farming and is of great significance to the economic development of aquaculture. By investigating different farmed fish, a large number of studies have shown that growth is mainly affected by environment, genes, and gene-environment interactions; specifically:(1) The environment is the external cause of growth trait regulation, and its impact on growth has generally presented a pattern of dosage effect. Excessive or insufficient amounts of several major environmental factors, such as temperature, light and nutrition, may have adverse effects on the growth of fish. Therefore, seeking optimal conditions becomes the ultimate goal of setting the best aquaculture environment. Additionally, regulating various environmental factors in modern aquaculture possesses significant application potential. (2) Genes are the internal factors that regulate growth traits, and their effects on growth have shown, largely, a relationship of causal effect. Single nucleotide polymorphisms, gene structural variations, ploidy changes, and transgenes of certain genes have shown statistically significant effects on fish growth. Since growth is a complex quantitative trait that is controlled by multiple genes, finding the major genes and then using them in selective breeding becomes an important method for improving growth. The technology of next generation sequencing presents strong advantages in the screening of growth-related candidate genes and in molecular-assisted selection. (3) The influence of gene-environment interactions on growth mainly derives from the different adaptability of genotypes to different environmental conditions, which is characterized by specificity and complexity. Therefore, quantitative research into gene-environment interactions is very limited at present. However, it may be important to consider the gene-environment interactions before developing a program of large-scale commercial breeding. In summary, a full understanding of the impacts of environment, genes, and gene-environment interactions on growth can facilitate better management of fish growth, thereby minimizing cultivation costs and maximizing the ecological benefits.