Institute of Marine Research, IMR, Postboks 1870 Nordnes, 5817 Bergen, Norway.
Institute of Marine Research, IMR, Postboks 1870 Nordnes, 5817 Bergen, Norway.
Comp Biochem Physiol A Mol Integr Physiol. 2020 Sep;247:110717. doi: 10.1016/j.cbpa.2020.110717. Epub 2020 May 4.
The Atlantic salmon aquaculture industry relies on adjustments of female broodstock spawning season to meet the demand for delivery of embryos outside the natural spawning season. Earlier results from zebrafish have shown that parental micronutrient status program offspring metabolism. Therefore, the main hypothesis of this study was to investigate if out-of-season (off-season) broodstock (spawning in June, in land-based recirculation systems) and their offspring deviate in micronutrient status when compared to broodstock and offspring from normal spawning season. Both seasons of female Atlantic salmon broodstock were fed the same diet and starved for approximately the same time interval prior to spawning. We compared nutrients related to the 1C metabolism (vitamin B12, folate, vitamin B6, methionine), free amino acids (FAAs) and lipid classes in broodstock muscle and liver tissues, and during offspring ontogeny. In general, the off-season broodstock showed higher levels of folate, vitamin B6 and selected FAAs in muscle tissue, and higher levels of folate and lipids (cholesterol and sphingomyelin) in liver tissue compared to normal-season. Furthermore, embryos from off-season had reduced amounts of all the measured lipid classes, like cholesterol and sphingomyelin, and lower levels of one type of folate and changes in FAAs and N-metabolites. We discovered significant differences between the seasons in mRNA levels of genes controlling fatty acid synthesis and 1C metabolism in both broodstock liver and offspring. Moreover, for genes controlling the methylation of DNA; both maintenance and de novo DNA methyltransferases (DNMTs) were expressed at higher levels in off-season compared to normal-season offspring. Our results show, in general that normal spawning season broodstock allocated more nutrients to eggs than off-season. Our results indicate a potential for improved maturation for off-season group to obtain a higher offspring growth potential, and this argues for a reassessment of the nutritional influence from broodstock to offspring and the consequences through nutritional programming.
大西洋鲑鱼养殖业依赖于调整雌亲鱼的产卵季节，以满足在自然产卵季节之外输送胚胎的需求。先前对斑马鱼的研究结果表明，亲代的微量营养素状态会影响后代的代谢。因此，本研究的主要假设是调查非产卵季节（淡季）亲鱼（在陆基循环系统中于 6 月产卵）及其后代与正常产卵季节的亲鱼和后代相比，在微量营养素状态上是否存在差异。两个季节的雌性大西洋鲑鱼亲鱼都喂食相同的饮食，并在产卵前大约相同的时间间隔内禁食。我们比较了与 1C 代谢（维生素 B12、叶酸、维生素 B6、蛋氨酸）、游离氨基酸（FAAs）和脂质类有关的营养素在亲鱼肌肉和肝脏组织中的含量，以及在后代个体发育过程中的含量。一般来说，淡季亲鱼肌肉组织中的叶酸、维生素 B6 和部分 FAAs 水平较高，肝脏组织中的叶酸和脂质（胆固醇和神经鞘磷脂）水平较高，与正常季节相比。此外，淡季胚胎的所有测量脂质类（如胆固醇和神经鞘磷脂）的含量都降低，一种类型的叶酸和 FAAs 和 N-代谢物的水平也降低。我们发现，两个季节的亲鱼肝脏和后代中控制脂肪酸合成和 1C 代谢的基因的 mRNA 水平存在显著差异。此外，对于控制 DNA 甲基化的基因，维持和从头 DNA 甲基转移酶（DNMTs）在淡季的表达水平均高于正常季节的后代。我们的研究结果表明，一般来说，正常产卵季节的亲鱼比淡季的亲鱼向卵子分配了更多的营养物质。我们的研究结果表明，淡季亲鱼可能具有更好的成熟度，以获得更高的后代生长潜力，这就需要重新评估亲鱼对后代的营养影响及其通过营养编程产生的后果。
