1. Pacic Oyster Physiological Response to Disease under Variable Environmental Regimes Emma Timmins-Schiman, Elene Dorfmeier, Paul McElhany, Shallin Busch, Steven Roberts & Carolyn Friedman University of Washington PCSGA 2010

2. Objective How do environmental stressors, such as ocean acidification (OA) and elevated temperature, affect oyster larvae survival and physiology when challenged by disease?

3. Experimental Plan How do environmental changes affect the host-pathogen relationship? High OA Temp. Host Pathogen Vibrio photo: Waldor & RayChaudhuri, 2000, Nature

4. Outline Ocean acidification Environmental stress and physiology Temperature and the C. gigas-V. tubiashii relationship OA effects on C. gigas Current work: OA & V. tubiashii Hi OA T

5. Outline Ocean acidification Environmental stress and physiology Temperature and the C. gigas-V. tubiashii relationship OA effects on C. gigas Current work: OA & V. tubiashii Hi OA T

6. Ocean Acidication 1000 ppm Increased CO2 in atmosphere 380 ppm Increased oceanic CO2 = lower oceanic pH

7. Environmental Stress Growth Reproduction Normal Environment Immune response General metabolism Environmental Stress Growth Reproduction Immune response General metabolism pH

8. Outline Ocean acidification Environmental stress and physiology Temperature and the C. gigas-V. tubiashii relationship OA effects on C. gigas Current work: OA & V. tubiashii Hi OA T

9. Temperature & V. tubiashii Two temperatures: 12oC & 25oC V. tubiashii challenge in both temperatures 3 day trial Immune response genes: C-jun kinase NfkB Up-regulate immune defenses: -ROS -inflammatory response

10. Temperature & V. tubiashii = 12oC = 25oC * =12oC + Vt * =25oC + Vt 1 2 3

11. Temperature & V. tubiashii Assay Development n=4 n=4 n=3 n=4 n=2 n=3 n=2 n=2 12oC 25oC 12oC 25oC 12oC 25oC 12oC 25oC

12. Outline Ocean acidification Environmental stress and physiology Temperature and the C. gigas-V. tubiashii relationship OA effects on C. gigas Current work: OA & V. tubiashii Hi OA T

13. Eects of OA on Development Strip-spawned and pooled sperm and eggs Fertilized eggs in pCO2-equilibrated water 380 ppm 840 ppm Time to developmental stage at 1 hour (2-cell) 2 hours (>4-cell) 5 hours (hatched) 17 hours 24 hours

14. Eects of OA on Development Timeline of C. gigas Larval Development Fertilization 2-cell 0h Developmental Stage 4-cell 1h hatching 2h 5h Time Post-Fertilization veliger 17h 24h

15. Eects of OA on Development =380 ppm =840 ppm Proportion Eggs in Cleavage *

16. Eects of OA on Development =380 ppm =840 ppm Proportion Larvae Hatched *

17. Eects of OA on Development A smaller proportion of larvae in elevated pCO2 develop at the normal rate Implications for physiological anomalies and calcification SEM Photo: Carla Stehr

18. Eects of OA on Development General stress response genes Cytochrome P450 oxidase (CytP450) Peroxiredoxin 6 (Prx6) Heat shock protein 70 (Hsp70) 1.0 0.8 Proportion Hatched 0.6 0.4 0.2 0.0 5 5 17 17 24 24 Time Post Fertilization (Hours)

19. Outline Ocean acidification Environmental stress and physiology Temperature and the C. gigas-V. tubiashii relationship OA effects on C. gigas Current work: OA & V. tubiashii Hi OA T

20. OA & V. tubiashii Study in progress in collaboration with NWFSC (P. McElhany et al.) Planned 3 weeks: spawning through settlement 4 pCO2 treatments 280, 380, 750, 2000 ppm 24-hour V. tubiashii exposure Data collection: Mortality Physiology (gene expression) Morphology & calcification Genotype-linked survival

21. = calcified OA & V. tubiashii = partially calcified Calcification at 48 hours post-fertilization = uncalcified

22. Conclusions Ocean acidification has significant effects on C. gigas larval development. OA may inhibit and depress larval response to other environmental stressors, including disease. Elevated temperatures, such as 25oC, have effects on the host-pathogen interaction.

23. Acknowledgements Funding: Saltonstall-Kennedy Grant (NOAA), NOAA Aquaculture Program student support University of Washington Moose ODonnell Sam White Taylor Shellfish Joth Davis Ed Jones Vicki Jones NOAA Northwest Fisheries Science Center Jason Miller Mike Maher Sarah Norberg