Abstract

Pacific oyster [Crassostrea gigas (Thunberg)] broodstock were hatchery-conditioned with either a mixed algal diet of Dunaliella tertiolecta, Tetraselmis suecica and Rhodomonas sp. [1:1:1, on a dry weight (DW) basis] (Control), a single diet of D. tertiolecta (Duna) or a single diet of D. tertiolecta supplemented with an emulsion rich in eicosapentaenoic (20:5n-3) and particularly docosahexaenoic acid (22:6n-3) (Duna+Em). Oysters were spawned after a conditioning period of 7 and 8 weeks and larvae were reared for 1 week on an Isochrysis galbana (clone T-Iso) diet. The percentage recovery of D-larvae from eggs of Control-fed oysters and Duna+Em-fed oysters was not significantly different (80% and 63% after 7 weeks of conditioning; 87% and 74% after 8 weeks of conditioning, respectively] but was much higher than from eggs produced by Duna-fed oysters (24% and 41% after 7 and 8 weeks of conditioning, respectively). A reduction in the percentage recovery of D-larvae as a result of temperature or salinity stress was most severe in eggs from Duna-fed oysters. Neither the broodstock diet nor the conditioning period affected the size of eggs or D-larvae, larval performance, or lipid content and lipid class distribution of the eggs. The fatty acid composition of the eggs was modified by the fatty acid composition of the algal diet and the lipid emulsion. The supplementation of the emulsion resulted in a pronounced increase in the percentage of 22:6n-3 in the polar (PL) and neutral lipids (NL) of the eggs (4.0–13.4% and 8.5–14.7% in NL and PL, respectively). The egg lipids (7–8 ng egg–1) contained about 62% NL and were dominated by triglycerides (TAG), which made up 65% of the NL. The major phospholipids were phosphatidylethanolamine (PE), ceramide aminoethylphosphonate and phosphatidylinositol (CAEP+PI), phosphatidylserine (PS) and phosphatidylcholine (PC). Regardless of the broodstock diet treatment, the PL fraction contained high percentages of non-methylene-interrupted dienes (NMID) and plasmalogens (detected as dimethyl acetals).

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.