1. Immune parametres of mussels treated with Prestige fuel oil M. Camino Ordás, Joan Albaiges, Josep M. Bayona, Amando Ordás and Antonio Figueras Instituto de Investigaciones Marinas (Vigo) Centro de Investigación y Desarrollo (Barcelona) Misión Biológica de Galicia (Pontevedra)

2. Inespecific system  no antibody production Cellular defenseHumoral defense Phagocytosis Respiratory burst NO production Lysozyme Lectins Prophenoloxidase SERUM SOLUBLE FACTORSHEMOCYTES External barriers Hemocytic infiltration Immune system of bivalve molluscs

3. contaminants depression in immune system infection by pathogens MORTALITY important economical losses in Galicia, one of the main Mediterranean mussel producers worldwide To assess the influence of the Prestige fuel oil on the immune response of Mediterranean mussel. Objective of this work

4. contaminants depression in immune system infection by pathogens MORTALITY important economical losses in Galicia, one of the main Mediterranean mussel producers worldwide To assess the influence of the Prestige fuel oil on the immune response of Mediterranean mussel. Objective of this work

5. contaminants depression in immune system infection by pathogens MORTALITY important economical losses in Galicia, one of the main Mediterranean mussel producers worldwide To assess the influence of the Prestige fuel oil on the immune response of Mediterranean mussel. Objective of this work

6. contaminants depression in immune system infection by pathogens MORTALITY important economical losses in Galicia, one of the main Mediterranean mussel producers worldwide To assess the influence of the Prestige fuel oil on the immune response of Mediterranean mussel. Objective of this work

7. contaminants depression in immune system infection by pathogens MORTALITY important economical losses in Galicia, one of the main Mediterranean mussel producers worldwide To assess the influence of the Prestige fuel oil on the immune response of Mediterranean mussel. Objective of this work

8. Methodology +1 kg fuel+2 kg fuel control Monthly sampling during four months Histology. Immune parametres: Cellular: hemocyte viability, phagocytosis, NO production, chemiluminescence (CL). Humoral: protein concentration and lysozime activity. PAH concentration in water and mussel tissue (gills and digestive gland). tank 1tank 2tank 3

9. Results - No granulocytomes or neoplasia - Mytilicola in 68% of sampled animals 1. HISTOLOGY

10. 2. IMMUNE PARAMETRES df Viab.Phagoc. CL NOProteinLisoz. Month (M)30.008 ** 252.750.0003 ** 5273.16 ** 0.04370.41 ** Treatment (T)20.002266.590.0001 * 536.080.081*54.98 ** M  T60.008 ** 143.370.0002 ** 2611.54 * 0.01024.92 * Error360.002146.120.00001015.160.0208.65 2.1. Mean squares (34 factorial ANOVA): No significant differences in phagocytic activity and significant differences in protein concentration. Remaining parametres: interaction between month and treatment.

11. 2.2. One way ANOVA (without taking into account the sampling month): significant differences in protein concentration and lysozyme activity. 2.3. Least square means: TreatmentViab.Phagoc.CLNOProteinLysoz. 2 kg0.220a11.080a0.015a52.770a0.242a7.507ab 1 kg0.219a13.890a0.013a50.120a0.283ab9.636a 0 kg0.236a19.108a0.010a61.200a0.381b5.943b Means followed by the same letter in a column are not statistically different according to the Waller-Duncan k- ratio t Test.

12. 3. PAH CONCENTRATION Prestige fuel oil Similar methylphenantrene profiles in mussel organs and Prestige fuel oil  real exposure to the fuel.

13. TPAH gill TPAH dig. gland Higher TPAH concentration (ng/ g) in digestive gland than in gill. Low TPAH conc. in control mussels. Excepting gill from the first month, organs treated with 2 kg of fuel show higher TPAH conc. than 1 kg- treated ones.

14. REGRESSION PROCEDURE: Model: [contam]= 0 +  1  MONTH +  2  TREATMENT Number of PAHs depending on each independent variable: ^ For comparisons between [PAH] and immune parametres, it would be more appropriate to use data from digestive gland, since [PAH] in gill is independent of our experimental design. Comparison between gland [PAH] and immune data (difficult due to the experimental design). Future analysis

15. Muchas gracias