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Nutrition and reproduction are key parameters in the interaction process leading to Crassostrea gigas oyster

summer mortality in France

Nutrition and reproduction are key Nutrition and reproduction are key parameters in the interaction process parameters in the interaction process leading to leading to CrassostreaCrassostrea gigasgigas oyster oyster

summer mortality in Francesummer mortality in France

JF Samain, L.Degremont, P.Soletchnik, M.Ropert, E.Bedier, J. Mazurié, JL.Martin, J.Moal, M.Mathieu, S.Pouvreau, C.Lambert, V.Boulo, JL.Nicolas, F.Le Roux, T.Renault, T.Burgeot, C.Bacher, J.Knoery, A.Huvet, P.Boudry as representatives of Morest partners

Styli 2003 Npumea

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GeneticsAge

PhysiologyDefenceNutrition

HOST PATHOGEN

ENVIRONMENT

Genetics

VirulenceNutrition

Temperature, Salinity, O2, Trophic conditions, Stress and Pollution

SummerSummer mortalitymortality isis a a multifactorialmultifactorial systemsystem

…2001-2006 MOREST Partnership 15 labs and 70 contributors

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e r3 main issues3 main issues3 main issues

WhatWhat are are thethe differentdifferent main main factorsfactors implicatedimplicated in in summersummermortalitymortality ??

How How cancan wewe rankrank thesethese factorsfactors in an interaction in an interaction processprocess??

FromFrom thisthis knowledgeknowledge, , cancan wewe performperform a a riskrisk analysisanalysis andandwhatwhat are are thethe possibilitiespossibilities to to forecastforecast andand preventprevent C.gigas C.gigas oysteroyster summersummer mortalitiesmortalities??

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5

7

9

1 1

1 3

1 5

1 7

1 9

2 1

Tem

péra

ture

moy

enne

(PM

±1h)

B D V

1/ 1/ TemperatureTemperature : a : a windowwindow of of riskrisk isis openedopened overover 19°C 19°C

0.000.100.200.300.400.500.600.700.800.901.001.101.201.30

janv 00 juil 00 janv 01 juil 01 janv 02 juil 02 janv 03 juil 03 janv 04 juil 04% M

orta

lité

Jour

naliè

re M

oyen

5

7

9

1 1

1 3

1 5

1 7

1 9

2 1

Tem

péra

ture

moy

enne

(PM

±1h)

B D V

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for 10 for 10 daysdays//mapmap((AtlanticAtlantic area)area)

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1 2 3 4 1 2 3 41 2 3 4 1 2 3 4june july august september

Mortality dynamics in France

Arcachon

Marennes

Bretagne

Normandie

P P

P P

P

P

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Gametogenesis stages

North : DELAY

For temperature

For gametogenesisFor mortality

In the field, mortality occurs when oysters are at stage III. Depends on the temperature increase

89

1011121314151617181920212223

891011121314151617181920212223

avr mai juin juil août sept oct

2002

Temperature

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R. d’Auraysummer 2 18 mois18 mois 7,6 6,2 ----

summer 1 6 mois 6 mois 29,0 27,1 58,5

cumulated 34,4 31,6 > 58,5

G1 G2 G3

…mortality is mainly the first year, and a very low mortality rate is observed the second year

In areas demonstrating a rapid temperature increase…

Auray

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Baie des Veysété 2 18 mois18 mois 29,0

été 1 6 mois 6 mois 4,0

cumulée 31,8

G3

Mortality in the first or the second year depends on the thermal regime of the area

In cold areas, the main mortality is on the second year. Less than one year old oysters are preserved from mortality on this site.

Baie des Veys

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e rTemperature 19°CTemperature 19°C

TheThe date of date of thethe major major riskrisk dependsdepends on on thethe geographicgeographiclocation of location of thethe cultivatedcultivated area.area.

ItIt cancan bebe predictedpredicted for one site in a for one site in a windowwindow of 15 of 15 daysdays..

Cold areas : are to Cold areas : are to bebe identifiedidentified because because theythey dont dont demonstratedemonstrate anyany summersummer mortalitymortality eventevent thethe firstfirst yearyear. . Can Can bebe valorizedvalorized in in thethe future .future .

In areas In areas demonstratingdemonstrating a a rapidrapid temperaturetemperature increaseincrease, , mortalitymortality cancan affect affect lessless thanthan one one yearyear oysteroyster

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Food level controls the reproduction intensity

Juvenile and adult reproductive effort is similar in the same trophic condition

0

20

40

60

80

100

Gon

ad a

rea

on h

isto

gica

l slid

e (%

) Low Food LevelHigh Food Level

F M A M J J A S O N

Induced spawning

*

**

*

*

*

0

20

40

60

80

100

A M J J A

*

**

18 months old (2002)

6 month old (2004)

CN1CN3

CN0CN1CN3

3- Food level and reproduction:

ExperimentalExperimental approachapproach

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At the end of gametogenesis, mortality resulting from experimental infection was increasing with trophic and reproductive levels.

18 months (2002) 6 months (2004)

0

20

40

60

80

CN0 CN1 CN3

Mor

talit

és J

2 (%

)

cohabitation

0

20

40

60

80

CN1 CN3

Mor

talit

és J

4 (%

)

injection

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0

0 .1

0 .2

0 .3

1 0 1 5 2 0 2 5T e m p e r a tu r e (° C )

Res

pira

tion

rate

(mgO

2.h-1

.cm

-1) C N 3

C N 1C N 0

Gametogenesis is energy expensive

Metabolic demand increased with temperature

- with reproductive stages

- with food level which controls reproduction effort

Energetic aspects :

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40

50

60

70

80

Abs

orpt

ion

effic

ienc

y (A

E, %

) CN0

CN1CN3

AVRIL MAI JUIN JUILLET

Ingestion increased with food level and gametogenesis intensitybut absorption efficiency decreased

0

30

60

90C

onso

mm

atio

n in

divi

duel

le

(10

6 cell

.h-1

.ind-1

)CN0CN1CN3

Ponte

AVRIL MAI JUIN JUILLET

0

5

10

15

20

25

30

0 5 10 15 20 25

Température (°C)

Ass

imila

ted

ener

gy (J

.h-1

.g-1

) Gigarepro 2004Gigarepro 2003Gigarepro 2002Bougrier et al. (1995)

0

5

10

15

20

25

30

0 5 10 15 20 25

Température (°C)

Ass

imila

ted

ener

gy (J

.h-1

.g-1

) Gigarepro 2004Gigarepro 2003Gigarepro 2002Bougrier et al. (1995)

0

5

10

15

20

25

30

0 5 10 15 20 25

Température (°C)

Ass

imila

ted

ener

gy (J

.h-1

.g-1

) Gigarepro 2004Gigarepro 2003Gigarepro 2002Bougrier et al. (1995)

Energy acquisition decreased beyond 20°C temperature for mature oysters

(Without gametogenesis)

(With gametogenesis)

Energetic aspects :

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Susceptible: 43 %Resistant : 7 %Control 2N: 24%Control 3N: 7%Wild spat (15%)

Auray site

0

10

20

30

40

50

60

70

80

90

Z L P F C AD

AB

M J X U W T Q CNA

CNF

AC

R D S I Y H A N K

Mor

talit

és (%

)

5- Genetic effect : divergent generation G2

Possible selection and high heritability

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R and S AURAY 2002 Reproductive effort: 18 months

R and S AURAY 2002

MORTALITY

Histologie quantitative

-- In 2002 the reproductive strategy appeared different for R and S.

- S had a higher reproductive effort

- R had a total spawning contrary to S

- Mortality affected S

0%

10%

20%

30%

May-1rst 31-May 30-June 30-July 29-Aug

Cum

ulat

ive

Mor

talit

y(%

)

0

25

50

75

100

16-avr 17-mai 16-juin 17-juil 16-août 16-sept 16-oct

Date

Gon

adPe

rcen

tage

in to

tal

(%)

SR

GONAD

19°C

19°C

Quantitative histology

LPI S.Pouvreau

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2 0

2 5

3 0

3 5

4 0

4 5

5 0

5 5

6 0

6 5

7 0

11-m

ars

18-m

ars

25-m

ars

1-av

r

8-av

r

15-a

vr

22-a

vr

29-a

vr

6-m

ai

13-m

ai

20-m

ai

27-m

ai

3-ju

in

10-ju

in

17-ju

in

24-ju

in

1-ju

il

8-ju

il

15-ju

il

22-ju

il

29-ju

il

5-ao

ût

12-a

oût

19-a

oût

26-a

oût

2-se

pt

9-se

pt

16-s

ept

indi

ce d

e W

alne

- M

ann

1 5 c m 7 0 c m

mars maiavril juin juillet août sep2 0

2 5

3 0

3 5

4 0

4 5

5 0

5 5

6 0

6 5

7 0

11-m

ars

18-m

ars

25-m

ars

1-av

r

8-av

r

15-a

vr

22-a

vr

29-a

vr

6-m

ai

13-m

ai

20-m

ai

27-m

ai

3-ju

in

10-ju

in

17-ju

in

24-ju

in

1-ju

il

8-ju

il

15-ju

il

22-ju

il

29-ju

il

5-ao

ût

12-a

oût

19-a

oût

26-a

oût

2-se

pt

9-se

pt

16-s

ept

indi

ce d

e W

alne

- M

ann

1 5 c m 7 0 c m

mars maiavril juin juillet août sepmars maiavril juin juillet août sep

Evolution du potentiel toxique des eaux et sédiments à Perquis

-20

0

20

40

60

80

100

14 mai 0

3

26 mai 0

3

23 juin 03

09 sept 0

3

% n

et d

'ano

mal

ies

eausediment

1 month NH4+ increased in the sediment and foram

population decreased

Toxicity in the sediment and water column

1 month decrease of dry weight in oyster

Oyster mortality higher near by the sediment

6- Stress is necessary : effect of sediment proximity 6- Stress is necessary : effect of sediment proximity

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HSP increased in S oyster contrary to R ones40

6080

100120140160180200220240

19-a

pr23

-apr

27-a

pr1-

may

5-m

ay9-

may

13

-may

17-m

ay21

-may

25-m

ay29

-may

2-ju

ne6-

june

10-ju

ne14

-june

18-ju

ne22

-june

26-ju

ne

HS

P

HSP-R15 HSP-R70HSP-S15 HSP-S70

S15

S70

R70

R15

mg

70 /g

pro

t

-203080

130180230280330380

22/0

4/20

03

29/0

4/20

03

06/0

5/20

03

13/0

5/20

03

20/0

5/20

03

27/0

5/20

03

03/0

6/20

03

10/0

6/20

03

17/0

6/20

03

24/0

6/20

03

mg

egg

prot

ein/

mg

DW

oys

ter

S 15R 15

-203080

130180230280330380

22/0

4/20

03

29/0

4/20

03

06/0

5/20

03

13/0

5/20

03

20/0

5/20

03

27/0

5/20

03

03/0

6/20

03

10/0

6/20

03

17/0

6/20

03

24/0

6/20

03

mg

egg

ptot

ein/

oyst

erD

W S 70R 70

70 cm

15 cm

Sediment

HSP70

Ovocyte mg/DWmg

Partial spawnings and rematuration processes were more intense near by the sediment for S oysters.

Why? Sediment stress and reproduction interactions?

6- Stress is necessary : effect of sediment proximity

6- Stress is necessary : effect of sediment proximity

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Hyalinocytes

0

50

100

150

200

April May

June

July

AugustSep

tember

RO

S pr

oduc

tion

(arb

itrar

y un

it)R

S

0

5

10

15

20

25

April May June July August September

Phag

ocyt

osis

(% a

ctiv

e ce

lls)

R

S

Hyalinocytes

0,E+00

1,E+05

2,E+05

3,E+05

4,E+05

5,E+05

6,E+05

7,E+05

April May June July August September

conc

entrat

ion

(cell p

er m

L) R

S

Phagocytosis

Hyalinocytesconcentration

ROS

In experimental conditions : hemocyte activities

HSP 701 HSP 70 only increased in S oysters when temperature increased from 13 to 19°C

Catalaseand SOD2

A catalase activity and a SOD expression decreased more in S oyster compared to R ones

3ROS increased in S oyster

for 2 months before mortality

4 Phagocytosis increased a month before mortality

5 Hyalinocyte concentration increased more on S oyster

vs R ones just before mortality

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-- OysterOyster nearnear by by thethe sedimentsediment (15cm) (2003)(15cm) (2003)Injected DonorRecipient oyster

40%92%85%43%94%

16 May16 June8 July

16 July31 July

3.3%87%95%23%35%

Transmission : higher susceptibility of recipient oysters between June 16th and July 31rst near by the sediment (15cm) (2003)

ExperimentalExperimental infections: challenge by cohabitation infections: challenge by cohabitation VibrioVibrio splendidussplendidus ((MelMel 32)32)

7- Infection is conditional :7- Infection is conditional :

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Débits et Flux en nitrates et MES (moy annuelles total BDV)Mortalités moyennes

0

20

40

60

93/94 94/95 95/96 96/97 97/98 98/99 99/00 00/01 01/02 02/03

m3/s % mort

0

500

1000

1500

g/s

QFlux NO3Flux MESmort ann

8- Effect of annual water outflow from watersheds on mortality

NO3, Suspended Matter fluxes and Mortality

Annual rain and watershed outflow can be correlated with summer mortality rate

Styli 2003 Npumea

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Stress Defense

Reproduction

An interaction process between stress, reproduction and defense is shown

OriginOrigin of R of R andand S S geneticgenetic differencedifference?? Looking for the gene concerned…

In conclusion

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44-- PhytoPhyto levellevel

66--Opportunistic Opportunistic PathogensPathogens

Mortality Date

33--output output fromfromwatershedswatersheds A

mpl

ifica

tion

Environment

22--ReproductionReproduction

77--geneticsgenetics

55--StressStressand

and

Styli 2003 Npumea

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e rPartnership

PhysiologyLaboratoire Conchylicole de Poitou-Charentes (LCPC),

IFREMER, La TrembladeLaboratoire Conchylicole de Bretagne (LCB), IFREMER, La

Trinité sur mer Laboratoire Conchylicole des Pays de la Loire (LCPL), IFREMER,

BouinLaboratoire Conchylicole de Normandie (LCN), IFREMER,Port en

BessinCentre de Recherche en Ecologie Marine et Aquaculture

(CREMA), CNRS-IFREMER, L’HoumeauLaboratoire de Physiologie des Invertébrés (LPI), IFREMER,

PlouzanéLaboratoire de Biologie et Biotechnologies Marines (LBBM),

Université de CaenStation de Biologie Marine, Muséum National d’Histoire Naturelle,

Concarneau

PathologyLaboratoire de Génétique et

Pathologie (LGP), IFREMER, La Tremblade

Laboratoire de Biologie et d’Environnement Marins (LBEM), Université de la Rochelle

EcotoxicologyDEL/PC, IFREMER, Nantes(en attente 2002)Laboratoire des sciences de

l'environnement marin (LEMAR), Université de Bretagne Occidentale ; Institut Universitaire Européen de la Mer, Plouzané

ProfessionStructures régionales

(SMIDAP, CREAA, SMEL, CEPRALMAR)

Ecloseurs-nurseursProducteurs

GeneticsLaboratoire de Génétique et Pathologie

(LGP), IFREMER, La TrembladeSyndicat des Sélectionneurs Avicoles et

Aquacoles Français (SYSAAF), RennesLe Centre Régional d’Expérimentation et

d’Application Aquacole (CREAA), Le Château d’Oléron

ImmunologyDéfense et Résistance chez les

Invertebrés Marins (DRIM), CNRS-IFREMER, Université Montpellier 2

Laboratoire des sciences de l'environnement marin (LEMAR), Université de Bretagne Occidentale; Institut Universitaire Européen de la Mer, Plouzané

Environnement DEL-RA réseaux et

modélisation

15 labs and 70 contributors

Manythank

s to all

of the

MOREST communi

ty