Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, UK.
Institute of Marine Research (formerly National Institute of Nutrition and Seafood Research), Nordnes, Bergen 5817, Norway.
Comp Biochem Physiol B Biochem Mol Biol. 2019 Nov;237:110327. doi: 10.1016/j.cbpb.2019.110327. Epub 2019 Aug 25.
Previously we showed that, for optimum growth, micronutrient levels should be supplemented above current National Research Council (2011) recommendations for Atlantic salmon when they are fed diets formulated with low levels of marine ingredients. In the present study, the impact of graded levels (100, 200, 400%) of a micronutrient package (NP) on vertebral deformities and bone gene expression were determined in diploid and triploid salmon parr fed low marine diets. The prevalence of radiologically detectable spinal deformities decreased with increasing micronutrient supplementation in both ploidy. On average, triploids had a higher incidence of spinal deformity than diploids within a given diet. Micronutrient supplementation particularly reduced prevalence of fusion deformities in diploids and compression and reduced spacing deformities in triploids. Prevalence of affected vertebrae within each spinal region (cranial, caudal, tail and tail fin) varied significantly between diet and ploidy, and there was interaction. Prevalence of deformities was greatest in the caudal region of triploids and the impact of graded micronutrient supplementation in reducing deformities also greatest in triploids. Diet affected vertebral morphology with length:height (L:H) ratio generally increasing with level of micronutrient supplementation in both ploidy with no difference between ploidy. Increased dietary micronutrients level in diploid salmon increased the vertebral expression of several bone biomarker genes including bone morphogenetic protein 2 (bmp2), osteocalcin (ostcn), alkaline phosphatase (alp), matrix metallopeptidase 13 (mmp13), osteopontin (opn) and insulin-like growth factor 1 receptor (igf1r). In contrast, although some genes showed similar trends in triploids, vertebral gene expression was not significantly affected by dietary micronutrients level. The study confirmed earlier indications that dietary micronutrient levels should be increased in salmon fed diets with low marine ingredients and that there are differences in nutritional requirements between ploidies.
先前我们表明，为了获得最佳生长，当以低水平的海洋成分来配制饲料喂养大西洋鲑鱼时，其微量营养素水平应根据当前的美国国家研究委员会（2011 年）建议进行补充，以高于其水平。在本研究中，我们确定了在投喂低海洋成分饲料的二倍体和三倍体鲑鱼幼鱼中，添加不同水平（100%、200%和 400%）的微量营养素包（NP）对脊椎畸形和骨基因表达的影响。在两种倍性中，随着微量营养素补充的增加，放射可检测到的脊柱畸形的发生率均降低。平均而言，在给定的饮食中，三倍体的脊柱畸形发生率高于二倍体。微量营养素补充尤其减少了二倍体融合畸形的发生率，并减少了三倍体的压缩和间隔畸形。在每个脊柱区域（颅、尾和尾鳍）中受影响的脊椎的发生率在饮食和倍性之间存在显著差异，且存在相互作用。在三倍体的尾部区域，畸形的发生率最高，而分级微量营养素补充在减少畸形方面的影响在三倍体中也最大。饮食影响脊椎形态，在两种倍性中，脊椎的长度与高度（L:H）比随着微量营养素水平的增加而普遍增加，而在倍性之间没有差异。二倍体鲑鱼中增加饮食微量营养素水平增加了几个骨生物标志物基因的表达，包括骨形态发生蛋白 2（bmp2）、骨钙素（ostcn）、碱性磷酸酶（alp）、基质金属蛋白酶 13（mmp13）、骨桥蛋白（opn）和胰岛素样生长因子 1 受体（igf1r）。相比之下，尽管三倍体中一些基因表现出相似的趋势，但脊椎基因表达不受饮食微量营养素水平的显著影响。该研究证实了之前的研究结果，即当投喂低海洋成分的饲料时，鲑鱼的饮食微量营养素水平应增加，并且两种倍性的营养需求存在差异。
