1. Cod Reproductive Ecology: Effect of dietary fatty acids on ovarian maturation, spawning time and quality of eggs and larvae. Maria C. Røjbek, PhD student, DTU Aqua, 2008-2011 Bornholms Lakseklækkeri, Øster Flak 2, DK-3730 Nexø Josianne Støttrup, Section for Coastal Ecology Jonna Tomkiewicz, Section for Population- and Ecosystem Dynamics Charlotte Jacobsen, Section for Aquatic lipids and Oxidation

2. Aim of the Phd study Baltic cod food chain and the reproductive success Lipid dynamics in cod Lipid dynamics in sprat and herring Lipid dynamics in plankton Comparisons between ecosystems, and between wild and captive cod fed dry feed with different lipid composition Effects of fatty acid composition on spawning time and egg- and larval quality Improvement of egg and larvae quality in cod farming through enhanced broodstock feed

3. Declined reproductive success of Baltic cod Köster F.W. et al., ICES Marine Science Symposia, 219: 294-306. 2003

4. Collection of Baltic cod, sprat, herring and zooplankton in the Central Baltic Sea

5. Histological analyses of cod gonads

6. Fatty acids in cod ovary and liver in relation to maturity stage of gonads

7. Lipid and fatty acid dynamic in clupeids in relation to sex, maturity stage and season

8. Seasonal variation in sprat

9. Bornholms Lakseklækkeri

10. St. Andrews Biological Station

11. Egg quality Fatty acid composition Pigment analysis Fertilisation rate Hatching rate Survival rate Sperm quality Fatty acid composition Motility Viability Larvae quality Fatty acid composition Viability Resistens to stress

12. Thank you for your attention