Circadian rhythm is the most important and universal biological rhythm in marine organisms. In this research, the movement behaviour of abalone (Haliotis discus hannai) was continuously monitored under a light cycle of 12 L:12D. It was found that the cumulative movement distance and cumulative movement time of abalone reached was highest from 00:00–03:00 h. The minimum values of maximum movement velocity occurred between 21:00–00:00 h, and a significant circadian cosine rhythm was exhibited during these periods (P < 0.05). Metabolomic analysis of cerebral ganglions of abalone was conducted at 06:00 h (6 M), 14:00 h (14 M), and 22:00 h (22 M) and 380, 385, and 315 metabolites with significant differences were identified in 6 M vs 14 M, 14 M vs 22 M, and 6 M vs 22 M, respectively (P < 0.05). With the alternation of day and night, the expression levels of phosphatidylcholine, 5-HT, N-acetyl-5-hydroxytryptamine, indole-3-acetaldehyde, hypoxanthine, and deoxyinosine declined significantly, while those of Lysophosphatidylcholines (lysoPC) (20: 5 (5Z, 8Z, 11Z, 14Z, 17Z)), lysoPC (22: 4 (7Z, 10Z, 13Z, 16Z)), lysoPC (16: 1 (9Z) / 0: 0), phosphatidylethanolamine (PE) (18: 1 (11Z) 22: 2 (13Z, 16Z)), and guanosine 5′-phosphate rose significantly. These 11 metabolites can be used as differential metabolic markers. These findings not only quantitatively describe the circadian movement behaviours of abalone, but also provide an initial analysis of the circadian mechanism of the physiological metabolic conversion of abalone, which in turn provides guidelines for light control and feeding strategy for use in aquaculture production.

昼夜节律是海洋生物中最重要，最普遍的生物节律。在这项研究中，鲍鱼（Haliotis discus hannai）的运动行为是在12 L：12D的光周期下连续监测的。研究发现，鲍鱼的累积移动距离和累积移动时间在00：00-03：00之间最高。最大运动速度的最小值出现在21：00–00：00 h之间，并且在这些时间段内表现出显着的昼夜节律（P  <0.05）。在06:00 h（6 M），14：00 h（14 M）和22:00 h（22 M）进行了鲍鱼脑神经节的代谢组学分析，确定了380、385和315种具有明显差异的代谢物分别为6 M与14 M，14 M与22 M和6 M与22 M（P  <0.05）。随着昼夜交替，磷脂酰胆碱，5-HT，N的表达水平-乙酰基-5-羟基色胺，吲哚-3-乙醛，次黄嘌呤和脱氧肌苷显着下降，而溶血磷脂酰胆碱（lysoPC）（20：5（5Z，8Z，11Z，14Z，17Z）），lysoPC（22：4（ 7Z，10Z，13Z，16Z）），lysoPC（16：1（9Z）/ 0：0），磷脂酰乙醇胺（PE）（18：1（11Z）22：2（13Z，16Z））和鸟苷5'-磷酸盐显着上升。这11种代谢物可用作差异代谢标记物。这些发现不仅定量地描述了鲍鱼的昼夜节律运动行为，而且还提供了对鲍鱼生理代谢转化的昼夜节律机制的初步分析，从而为水产养殖生产中的光照控制和饲养策略提供了指导。