Department of Biology, NTNU Norwegian University of Science and Technology, N-7491, Trondheim, Norway.
Faculty of Biosciences, Department of Animal and Aquacultural Sciences, Centre for Integrative Genetics, Norwegian University of Life Sciences, Ås, Norway.
Sci Rep. 2019 Jan 10;9(1):27. doi: 10.1038/s41598-018-37266-3.
The quality and relative amounts of dietary lipids may affect the health and growth of cultured Atlantic salmon. So far, little is known about their effects on the performance of the fish immune system during early life stages and, in particular their importance in the transition from endogenous nutrition (yolk) in the alevin stage to exogenous nutrition in the later fry stage. We investigated the immunomodulatory effects of fish oil, vegetable oil and phospholipid-rich oil in feeds for farmed Atlantic salmon using a transcriptomic approach. The experiment allowed a fine-scale monitoring of gene expression profiles in two tissues, the pyloric caeca of the intestine and the liver, in a 94 days-long first feeding experiment. The analysis of transcriptional profiles revealed that first feeding induced a strong immunomodulation in the pyloric caeca after 48 days of feeding, lasting up to day 94 and possibly beyond. On the other hand, the differential effect of the three dietary regimes was negligible. We interpret this upregulation, undetectable in liver, as a potentiation of the immune system upon the first contact of the digestive system with exogenous feed. This process involved a complex network of gene products involved in both cellular and humoral immunity. We identified the classical pathway of the complement system, acting at the crossroads between innate and adaptive immunity, as a key process modulated in response to the switch from endogenous to exogenous nutrition.
饮食中脂质的质量和相对含量可能会影响养殖大西洋鲑的健康和生长。到目前为止，人们对它们在早期生命阶段对鱼类免疫系统性能的影响知之甚少，特别是在从内源性营养（卵黄）向后期幼鱼阶段的外源性营养过渡期间的重要性。我们使用转录组学方法研究了鱼油、植物油和富含磷脂的油在养殖大西洋鲑饲料中的免疫调节作用。该实验允许在 94 天的首次喂养实验中，对两种组织（肠道的幽门盲囊和肝脏）的基因表达谱进行精细监测。转录谱分析表明，首次喂养在 48 天后诱导了幽门盲囊的强烈免疫调节，持续至第 94 天甚至更久。另一方面，三种饮食方案的差异影响可以忽略不计。我们将这种在肝脏中无法检测到的上调解释为消化系统与外源性饲料首次接触时免疫系统的增强。这个过程涉及到一个复杂的基因产物网络，参与细胞和体液免疫。我们确定了补体系统的经典途径，作为先天免疫和适应性免疫之间的交汇点，作为对从内源性到外源性营养转变的反应而被调节的关键过程。
