Selenium protects yellow catfish from low temperature damage via the perspective analysis of metabonomics and intestinal microbes

Abstract

Abstract Selenium is an essential trace element in animals, which can improve growth performance and anti-stress ability. Temperature is a crucial environmental factor affecting the health of fish, while Pelteobagrus fulvidraco (P. fulvidraco) can not tolerate low temperature. Does dietary selenium affect the resistance to low temperature stress of this fish? Metabolomics and microbiome analysis were used to investigate it. Feeding results showed selenium supplementation increased the weight gain rate (WGR), specific growth rate (SGR), and survival rate (SR) of P. fulvidraco, and decreased the feed conversion rate (FCR) (P > 0.05), under low temperature stress, selenium also enhanced the glutathione peroxidase (GSH-Px) activity, reduced the malondialdehyde (MDA) content in serum, but these differences were not significant (P > 0.05). Metabonomics analysis revealed lipids and lipid-like molles, organic acids and derivatives, fatty acyls were the mainly differential metabolites caused by selenium, among these, indoles and derivatives, steroids and steroid derivatives, glycerolipids and sphingolipids were significantly up-regulated, while erythrina alkaloids, organic oxygen compounds, organic nitrogen compounds and purine nucleosides were significantly down-regulated. Choline, linoleic acid and glycerophospholipid metabolism pathways, d-arginine and d-ornithine metabolism, valine, leucine, and isoleucine degradation and biosynthes pathways as well as pyrimidine metabolism pathways produced these metabolites. In addition, selenium supplementation also increased the diversity of intestinal microbes in P. fulvidraco and decreased the relative abundance of Plesiomonas under low temperature stress, however, the intestinal microbes change did not affect the metabolites production. In summary, selenium supplementation actived lipid, carbohydrate and amino acid metabolism for energy substances provision, meanwhile reduced oxidation and other harmful substances production, increased the intestinal microbes diversity of P. fulvidraco to improve the low temperature stress resistance.