Egg quality is essential for fish breeding and the healthy development of aquaculture. In the artificial breeding of , in which ovulation cannot occur spontaneously, it is difficult to determine a suitable time for collecting eggs artificially from mature broodstocks, and artificial egg collection is frequently delayed in the breeding of . Aging of ovulated eggs in the ovary or in the coelomic cavity is defined as over-ripening of eggs and is always associated with a decrease in egg viability. It would thus be useful to investigate variations in physiological and biochemical parameters and their effects on the quality of eggs during egg over-ripening, and to define those parameters that are correlated with egg vitality and could be used as quality markers. In this study, we examined the effects of delaying artificial spawning of mature broodstocks for 1 and 2 weeks. In group A, artificial spawning was not delayed, whereas in groups B and C, artificial spawning was delayed for 1 and 2 weeks, respectively. Variations in the phosphatases, malate dehydrogenase (MDH), sialic acid, total amino acids (AAs), and fatty acids of eggs were analyzed by means of biochemical analysis and GC-MS. We also examined the correlations between these biochemical parameters and fertilization rates. The results showed that after delaying spawning for 1 week, the fertilization rates in group B decreased significantly (<0.05), and that after a delay of 2 weeks, the fertilization rates of group C decreased to 31.89%. With the delay in spawning, the activities of acid phosphatase (ACP) decreased significantly (P<0.05, =0.705). In group A, the activity of MDH was significantly higher than that in group B and group C (=0.630). AA contents showed the same variation tendency, with the AA contents in group A and group B being higher than those in group C (=0.706). The contents of myristic acid (C_14:0), pentadecanoic acid (C_15:0), palmitic acid (C_16:0), palmitoleic acid (C_16:1n-7), α-linolenic acid (C_18:3n-3), and eicosapentaenoic acid (EPA) in 100 g fat were highest in group A and were significantly positively correlated with fertilization rates () and the ratio of docosahexaenoic acid (DHA) to EPA were significantly negatively correlated with fertilization rates. These results demonstrate that the egg vitality of was significantly reduced during over-ripening in the coelomic cavity. The changes in egg vitality were associated with several alterations in egg physiology and biochemical compositions. Some of the parameters of the eggs that changed during over-ripening were also suitable for the determination of egg quality. These phenomena suggest that during the over-ripening of eggs, the egg membrane becomes damaged, and that there is a mixing of the contents of eggs and ovarian fluid, which leads to a decrease in the compositions of AAs, types of fatty acids, and other biochemical substances. C_14:0, C_15:0, and C_16:0 are important energy storage materials, whereas C_20:5n-3 is the precursor of EPA, which confers anti-inflammatory properties to eggs. AA content is an important index of AA metabolism. Clearly, as indicated by the results of this study, decreases in these biomolecules could lead to decreases in the fertilization rates of eggs. ACP is an enzyme that is indicative of lytic processes and is involved in the degeneration of phospholipids, whereas MDH is a key-enzyme in the tricarboxylic acid cycle, which is consistent with our results showing that decreases in the activities of ACP and MDH can impair egg viability. In conclusion, changes in phosphatase, malate dehydrogenase, total amino acids and fatty acids are correlated with egg viability, and it is thus essential to collect eggs artificially within 1 week when the ovaria of broodstocks are maturing.