1. Pacific Oyster Physiological Response to
Disease under Variable Environmental
Regimes
Emma Timmins-Schiffman, 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 Acidification
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. Effects 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. Effects 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. Effects of OA on Development
=380 ppm
=840 ppm
Proportion Eggs in Cleavage
*
16. Effects of OA on Development
=380 ppm
=840 ppm
Proportion Larvae Hatched
*
17. Effects 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. Effects 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 O’Donnell
Sam White
Taylor Shellfish
Joth Davis
Ed Jones
Vicki Jones
NOAA Northwest Fisheries Science Center
Jason Miller
Mike Maher
Sarah Norberg