The metabolomics provides insights into the Pacific abalone (Haliotis discus hannai) response to low temperature stress

The low temperatures in winter, particularly the cold spells in recent years, have posed significant threats to China's abalone aquaculture industry. The low temperature tolerance of cultured abalone has drawn plenty of attention, but the metabolic response of abalone to low-temperature stress remains unclear. In this study, we investigated the metabolomic analysis of Pacific abalone (<i>Haliotis discus hannai</i>) during low-temperature stress. Pacific abalone used two strains of cultured abalone, namely the bottom-sowing cultured strain (DB) and the longline cultured strain (FS), which had different histories of low-temperature acclimation. The results revealed that eight of the top 10 shared differential expression metabolites of the two strains were carbohydrates. According to the results of the Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis, low-temperature stress primarily affected several metabolic pathways. These pathways include ABC transporters, carbohydrate digestion and absorption, starch and sucrose metabolism, lysine degradation, TCA cycle, the phosphotransferase system, the glucagon signaling pathway and pyruvate metabolism. The results suggest that Pacific abalone primarily regulates the expression of carbohydrates to enhance energy supply and anti-freezing protection. These findings are crucial for understanding the mechanism of low-temperature tolerance in Pacific abalone, and can help optimize culture strategies for high-quality abalone aquaculture development.