Abstract:Three experimental diets with fish oil, soybean oil and olive oil as different lipid source and a commercial diet as control were used to feed broodstock of tongue sole Cynoglossus semilaevis for 8 weeks to investigate the effects of different fat source on spawning performance, fatty acids composition in eggs and quality of larvae. Results showed that in terms of the relative fecundity, the control was the highest, followed by olive oil treatment, fish oil treatment, and soybean oil treatment as the lowest. The abnormal egg ratio of control was the lowest follwed by, fish oil treatment, olive oil treatment, and soybean oil treatment as the highest (9.77%, 14.53%, 19.4% and 17.35% respectively)(P＜0.05). Abnormal larva ratio among treatments was significantly different (P＜0.05) (3.34%, 3.12%, 8.85% and 17.35% respectively). Hatching rate of control was the highest, followed by fish oil treatment, olive oil treatment, and soybean oil treatment as the lowest (P＜0.05) (95.49%, 84.88%, 79.57% and 74.27% respectively). It indicated that during spawning period, a certain amount of n 3 HUFA in diet, especially docosahexenoic acid (DHA) needs to maintain egg development and larval growth. Oleic acid and linoleic acid (LA) were selectively retained and played an important roles in tongue sole egg development process. We conclude that soybean oil or olive oil or fish oil as a single lipid source of diets can not provide sufficient fatty acids for tongue sole C. semilaevis.
