THE EFFECT OF CLIMATE THE EFFECT OF CLIMATE CHANGE ON SOFT CHANGE ON SOFT SEDIMENT BIVALVES & SEDIMENT BIVALVES & THEIR PATHOGENS THEIR PATHOGENS
Emer Morgan Supervisors : Drs Culloty & Ramsay
PROPOSED CHAPTERS
Reproduction of C. edule & Reservoir Species Parasites & BacteriaReservoir Species Environmental Effects on MortalitiesNeoplasia & the Presence of a VirusTrematode Genetics
WORK TO DATEWork To Date Work To Date
INTRODUCTION: REPRODUCTION INTRODUCTION: REPRODUCTION Separate Sexes
Sexual Maturity at 18 months
Previous published studies on reproduction in Ireland 1977/78
Milder winters linked to reduced recruitment
Mussel settlement adversely effected by rainfall
INTRODUCTION: PARASITES & INTRODUCTION: PARASITES & BACTERIA BACTERIA
16 species of digenean parasite
First & second intermediate host
Leads to impaired growth, parasitic castration, possibly death
Rickettsisosis
Fig 1: Range of Fig 1: Range of C. edule C. edule
Fig 2: Digenean Trematodes
INTRODUCTION: RESERVOIR INTRODUCTION: RESERVOIR SPECIES SPECIES
Reservoir hosts are significant because they maintain parasites in the absence of the primary host (Criscione et al., 2005)
Species that carry the pathogen/parasite
Not the preferred host
But keep the parasite/pathogen in the area when preferred host is unavailable
S. plana A. tenuis
M. balthica M. edulis
Fig 3: Reservoir Species
MATERIAL & METHODS MATERIAL & METHODS
Flaxfort Strand Bannow Bay
Fig 4: Sampling Methodology
MATERIALS & METHODS MATERIALS & METHODS Salinity
Oxygen Levels
Temperature
Fig 5: Environmental Data
MATERIALS & METHODS MATERIALS & METHODS
Fig 6: Laboratory Work
PRELIMINARY RESULTS: PRELIMINARY RESULTS: ENVIRONMENTAL DATA ENVIRONMENTAL DATA
Bannow Bay Temperature Range 9.48°C –27.97°CAverage 17.61°C Salinity Range - Flaxfort Strand 35-36‰
-Bannow Bay 16-36 ‰
Fig 7: Temperature Readout – Bannow Bay Channel
PRELIMINARY RESULTS: COCKLE PRELIMINARY RESULTS: COCKLE MORPHOMETRICS MORPHOMETRICS
Moribund cockles from Bannow Bay largestBuried cockles from Flaxfort Strand larger than those from Bannow BayWhole weight (g) of moribund cockles from Bannow Bay decreasing for last 3 months
Fig 8: Average Lengths mm
PRELIMINARY RESULTS: PRELIMINARY RESULTS: RESERVOIR SPECIES RESERVOIR SPECIES
MORPHOMETRICS MORPHOMETRICS Flaxfort Strand mussels greater in length & weight
S. plana greater in length in Bannow Bay
M. balthica & A. tenuis no consistent relationship between size & site
Fig 9: Mussel Average Lengths mm
PRELIMINARY RESULTS: COCKLE PRELIMINARY RESULTS: COCKLE SEX RATIOS & REPRODUCTION SEX RATIOS & REPRODUCTION
CI of moribund cockles less than buried cockles Fluctuations in CI may indicate spawningGreater number of females in Flaxfort Strand (20♂:26♀)Greater number of males in Bannow Bay (61♂:55♀)
Fig 10: Condition Indices
PRELIMINARY RESULTS: MUSSEL PRELIMINARY RESULTS: MUSSEL SEX RATIOS & REPRODUCTION SEX RATIOS & REPRODUCTION
oGreater CI in Bannow Bay
oFluctuations throughout the study
oMore females in Flaxfort Strand, more males in Bannow Bay
Fig 11: Mussel Condition Index
PRELIMINARY RESULTS: PRELIMINARY RESULTS: PARASITES & PATHOLOGICAL PARASITES & PATHOLOGICAL CONDITIONS CONDITIONS oMytilicola intestinalis identified in C. edule & M. edulis
oMetacercariae & Sporocysts in C. edule
oMetacercaria only in M. edulis
oNematopsis spp. oocysts in C. edule & M. edulis
Fig 12: Range of conditions identified
PRELIMINARY RESULTS: PRELIMINARY RESULTS: PARASITES & PATHOLOGICAL PARASITES & PATHOLOGICAL CONDITIONS CONDITIONS o Neoplasia in C. edule
o Prokaryote inclusions
Deposits in C. edule tissues
Markings on S. plana, M. balthica & A. tenuis tissues
Hydrobia ulvae inhabiting moribund cockles
Fig 13: Range of items seen in C. edule
PRELIMINARY DISCUSSION PRELIMINARY DISCUSSION
Variation between sites
Moribund cockles largest c.f. previous Flaxfort Strand study
Decrease in moribund cockles whole weights
Abiotic Biotic
•Salinity range •More disturbed •Less exposed
•Size differences•Time of spawning •Infection levels
PRELIMINARY DISCUSSION PRELIMINARY DISCUSSION
CI of buried cockles greater than moribund
CI of moribund cockles in Bannow Bay greater
than Flaxfort Strand
Fluctuations in CI may indicate spawning
Differences in sex ratios – greater number of
females in Flaxfort
PRELIMINARY DISCUSSION PRELIMINARY DISCUSSION
Levels of M. intestinalis infection vary with
position in the sediment & species
Dignean trematodes in both C. edule & M. edulis
– but different levels & stages
Neoplasia identified in C. edule
Large items in the tissues, shell deposits
FUTURE PLANS
Future Work Future Work
ENVIRONMENTAL EFFECTS ON ENVIRONMENTAL EFFECTS ON MORTALITY MORTALITY
From May 2011-October 2011
Lab trials
Lasting 3-4months
Altering conditions e.g. Temperature, Oxygen levels
Observing the effects on bacteria, trematodes,
neoplasia
NEOPLASIA & PRESENCE OF A NEOPLASIA & PRESENCE OF A VIRUS VIRUS
Histology
TEM
Retroviral Activity o Commercial kit
o PERT assay
Heat Shock Proteins &
mutant p53
P53Hsp70
Hsp90
Fig 14: Hsp’s & virus particle
TREMATODE GENETICS TREMATODE GENETICS
14 sites 10-15 animals from each siteInduce cockles to shed Identify using keys e.g. de Montaudouin etal., 2009Extract DNA using methods of Leung et al., 2010Purify and sequence
Fig 15: identification key
OTHER TOPICS/ OTHER TOPICS/ COLLABORATIONS COLLABORATIONS
Contributing to study on cockle genetics
Planning to screen mussels from Bannow Bay to
check for hybrids (see Bignell et al., 2008)
Oral presentations at EMBS 2010
Funding and Partners
REFERENCEShttp://www.google.ie/imgres?imgurl=http://www.howbrewyou.com/wp-content/uploads/2008/06/refractometer.jpg&imgrefurl=http://www.howbrewyou.com/2008/06/22/reading-a-refractometer/&usg=__M7_1IGjt1DyX9bBIzTmc-ozadzk=&h=202&w=220&sz=8&hl=en&start=0&tbnid=0esyeVXaXGjrIM:&tbnh=135&tbnw=139&prev=/images%3Fq%3Drefractometer%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1T4GFRE_enIE371IE371%26biw%3D1297%26bih%3D565%26tbs%3Disch:1&um=1&itbs=1&iact=rc&dur=719&ei=MxdpTMO8Aarc4wb95pyZBA&oei=MxdpTMO8Aarc4wb95pyZBA&esq=1&page=1&ndsp=21&ved=1t:429,r:1,s:0&tx=62&ty=63http://www.google.ie/imgres?imgurl=http://images.drillspot.com/pimages/245/24508_300.jpg&imgrefurl=http://www.drillspot.com/products/75293/Extech_407510_Dissolved_Oxygen_Meter&usg=__tH0hHxCXlyAZLpX-deZUMgnZ5vc=&h=300&w=300&sz=91&hl=en&start=0&tbnid=FBuse2o59iwldM:&tbnh=143&tbnw=149&prev=/images%3Fq%3Doxygen%2Bmeter%26um%3D1%26hl%3Den%26rlz%3D1T4GFRE_enIE371IE371%26biw%3D1297%26bih%3D565%26tbs%3Disch:1&um=1&itbs=1&iact=rc&dur=313&ei=jBdpTLWqDIO-4gbmiZ2ZBA&oei=jBdpTLWqDIO-4gbmiZ2ZBA&esq=1&page=1&ndsp=23&ved=1t:429,r:20,s:0&tx=83&ty=85http://www.google.ie/imgres?imgurl=http://www.awi.de/typo3temp/pics/a50475809c.jpg&imgrefurl=http://www.awi.de/en/research/new_technologies/marine_aquaculture_maritime_technologies_and_iczm/projects/marine_aquaculture_projects/mytifit/&usg=__5OpQy2SRX7YNfCnfKgB1seQOLCE=&h=249&w=335&sz=122&hl=en&start=4&itbs=1&tbnid=g9_baBfSK01lKM:&tbnh=88&tbnw=119&prev=/images%3Fq%3Dmytilicola%2Bintestinalis%26hl%3Den%26gbv%3D2%26tbs%3Disch:1Bignell et al., 2008. Mussel Histopathology: effects of season, disease, and species. Aquatic Biology, 2, 1-15. http://www.google.ie/imgres?imgurl=http://www.pac.dfo-mpo.gc.ca/science/species-especes/shellfish-coquillages/diseases-maladies/images/gregpcc2.jpg&imgrefurl=http://www.pac.dfo-mpo.gc.ca/science/species-especes/shellfish-coquillages/diseases-maladies/pages/gregpcc-eng.htm&usg=__uDHcvLtHD9lWh5qSalRgi5k4lgk=&h=438&w=657&sz=48&hl=en&start=1&itbs=1&tbnid=RkX1yi0qsycsgM:&tbnh=92&tbnw=138&prev=/images%3Fq%3Dnematopsis%26hl%3Den%26gbv%3D2%26tbs%3Disch:1http://www.google.ie/imgres?imgurl=http://www.pac.dfo-mpo.gc.ca/science/species-especes/shellfish-coquillages/diseases-maladies/images/rcomu2.jpg&imgrefurl=http://www.pac.dfo-mpo.gc.ca/science/species-especes/shellfish-coquillages/diseases-maladies/pages/rcomu-eng.htm&usg=__M0Miyj0-49DK7TjrHN-Aj_QdmHA=&h=433&w=650&sz=27&hl=en&start=11&itbs=1&tbnid=pOcwHjZeB9akcM:&tbnh=91&tbnw=137&prev=/images%3Fq%3Drickettsiosis%2Bcockles%26hl%3Den%26gbv%3D2%26tbs%3Disch:1http://www.google.ie/imgres?imgurl=http://www.deeestuary.co.uk/images/hydcock.jpg&imgrefurl=http://www.deeestuary.co.uk/news1101.htm&usg=__mLL2GEjU7rD4e2_yzRL_Jniw8f8=&h=198&w=214&sz=18&hl=en&start=2&itbs=1&tbnid=iNMgUfFYPd9lBM:&tbnh=98&tbnw=106&prev=/images%3Fq%3Dhydrobia%2Bulvae%2Bin%2Bcockles%26hl%3Den%26gbv%3D2%26tbs%3Disch:1http://en.wikipedia.org/wiki/Hsp70http://en.wikipedia.org/wiki/Heat_shock_protein_90kDa_alpha_(cytosolic),_member_A1http://en.wikipedia.org/wiki/P53