鱼类消化道菌群与碳水化合物代谢

Gut microbiota and carbohydrate metabolism in fish

碳水化合物氧化分解是鱼类能量的重要来源。由于碳水化合物来源广泛、价格相对低廉,饲料中添加适量碳水化合物,不仅可以降低饲料成本,而且可以节约蛋白原料,减少氨氮排放。然而以往研究表明,鱼类摄入超量碳水化合物时会出现抗病力受损、生长迟缓、脂肪肝、死亡率升高等问题。鱼类消化道微生物参与宿主的糖、脂类和蛋白质等代谢过程,对动物营养代谢有重要的调控作用。提高鱼类对饲料的利用率,对鱼类增产、渔民增收具有重要的现实意义。本研究综述了鱼类对碳水化合物的代谢,以鱼类消化道微生物为出发点,阐述了鱼类消化道微生物调控碳水化合物代谢的方式与可能机制,旨在为鱼类高效利用碳水化合物以及节约饲料中蛋白质提供新视角。

Oxidative decomposition of carbohydrate is an important source of energy for fish. Since carbohydrates are relatively cheap, adding appropriate amounts of carbohydrates to the feed can save protein, reduce feed costs, and reduce ammonia nitrogen excretion. However, a large number of studies have shown that fish have low ability to utilize carbohydrate. When carbohydrates content in the feed exceeds a certain level, the fish will suffer from impaired disease resistance, growth retardation, fatty liver, and higher mortality. Gut microbiota participates in the metabolism of various nutrients such as carbohydrates, lipids and amino acids, which significantly affects the animal nutritional metabolic processes. Increasing the utilization rate of feed has important practical significance for increasing fish production and farmers’ income. This review starts from the carbohydrate metabolism of fish and targets the microbial flora of fish digestive tract. Further, it explains the ways and possible mechanisms associated with the regulation of fish carbohydrate metabolism by gut microbiota. This review may provide new perspectives for efficient carbohydrates usage and protein saving in fish culture.