Ingestion of Domoic Acid and Its Impact on King Scallop(Pecten maximus,Linnaeus 1758)

A simple method for spiking formulated feed with domoic acid (DA) was developed in this study. DA feed was prepared by mixing 0.15 mL 100 μg mL-1 DA with 0.1 g formulated feed, and drying the mixture at room temperature for 2 h. The prepared DA feed contained 0.19 pg DA per particle. Of the added DA, 46.72％ was retained in the feed. Relatively high DA retention (about 50％) was recorded after DA feed was soaked in water for 2h. Exposure to DA feed for 7d did not cause the increase of tissue DA level of adult king scallop (Pecten maximus) significantly in 60 d. The increase of their gonad index after DA exposure was not significantly different from the control. No significant change in DA level was found in spermary, ovary or fertilized eggs after DA exposure. These results indicated that DA excretion may be more efficient than DA accumulation under the current experimental conditions, and the mechanism of domoic acid incorporation in P. maximus may involve intracellular biotransformation.