Abstract:
Background As a famous and special aquatic breeding species, Siniperca chuatsi is prone to hepatobiliary diseases and other problems during the domestication process of artificial feed culture, which seriously restricts the stable development of its industry.
Objective This study aimed to explore the impact of feed domestication on the growth and liver metabolism of Siniperca chuatsi.
Methods Taking Siniperca chuatsi as the research object, the entire process from fry stocking to successful domestication and artificial feed culture was divided into three phases: the fry acclimation period, the artificial feed domestication period, and the artificial feed culture period. A blood glucose meter was used to detect the blood glucose levels of the fish during the artificial feed culture period, and growth-related traits of the fish were measured. liver samples were randomly collected from 8 Siniperca chuatsi in the undomesticated period, the artificial feed middle culture period, and the late culture period, respectively for untargeted metabolomics detection and comparative analysis.
Results The body weight and body height of Siniperca chuatsi measured on the 31st day of the artificial feed culture period were significantly higher than those on the 22nd day (P<0.05). Compared with the undomesticated group, the artificial feed middle culture period group (16th day of the culture period) had 915 differential metabolites, including 552 upregulated and 363 downregulated ones, the upregulated metabolites were mainly peptides and carboxylic acid derivatives, enriched in pathways such as metabolites pathways, amino acid biosynthesis, D-amino acid metabolism, and ABC transporter. Compared with the undomesticated group, the late culture period group (31st day of the culture period) had 951 differential metabolites, with 551 upregulated and 400 downregulated ones, the upregulated metabolites included peptides and carboxylic acid derivatives, enriched in pathways such as metabolic pathways, D-amino acid metabolism, ABC transporters, and protein digestion and absorption pathway. Compared with the middle culture period group, the late culture period group had 228 differential metabolites, including 140 upregulated and 88 downregulated ones. Among them, glycylleucine and glycylphenylalanine and others are significantly upregulated and enriched in glutathione metabolism; while prenol lipids long-chain fatty acids and others are downregulated and enriched in pathways like metabolism pathways and ABC transporter.
Conclusion Artificial diet domestication of Siniperca chuatsi was successfully carried out in a recirculating aquaculture system. It was found that domestication increases the liver metabolic burden of Siniperca chuatsi, possible reason lies in changes in metabolic pathways involved in liver metabolism, such as glycolysis, the TCA cycle, D-amino acid metabolism, and amino acid biosynthesis. Meanwhile, metabolic pathways including ABC transporters, protein digestion and absorption, and glutathione metabolism play a role in alleviating the liver burden. This study clarifies the effect of artificial feed domestication on the liver metabolism of Siniperca chuatsi, providing support for the domesticated culture of feed-fed Siniperca chuatsi in recirculating aquaculture systems.