This document summarizes the diagnostic tools and capabilities available at the European Community Reference Laboratory for Crustacean Diseases. It outlines the main diagnostic techniques used such as histology, electron microscopy, molecular diagnostics and antibodies. It also describes the laboratory's accreditation for specific diagnostic methods and its biosecure facilities. Experimental challenge studies are discussed as a tool for determining species susceptibility, using an example of testing European crustaceans for susceptibility to WSSV. The document concludes with an overview of current research areas.

1. Disease challenge models
Dr Grant Stentiford
European Community Reference Laboratory for Crustacean Diseases
Pathology and Parasite Systematics team, Cefas

2. Diagnosing disease in crustaceans
• Research/diagnostics tools are similar for use with other animal groups
• Histology provides a front-line tool for observations of deviations from normal
• Electron microscopy provides information on pathology/pathogens/life cycles
• Antibodies are available against most major crustacean pathogens
• Molecular diagnostics (e.g. PCR) are widely used to confirm pathogen type
• No reliable cell lines are available (e.g. for viral culture)
• Generally rely on a combination of the above for successful diagnosis

3. Diagnostic accreditation and in-house expertise
• Histology: ISO 17025 Method for testing crustaceans for
pathogens and notifiable diseases by histological analysis
• Molecular diagnostics: ISO17025 Flexible scope
accreditation for RT-PCR and PCR of fish, shellfish and
crustacean pathogens
• Experimental Facility: GLP accredited facility. Biosecure
containment facility for exotic pathogen work
• Capacity to work with a wide range of host species and all
globally significant pathogens (e.g. EC Directive listed,
OIE listed, emerging pathogens)

4. Typical challenge studies
Q. Are crustaceans from EU waters susceptible to WSSV?

5. Susceptibility testing

6. Viral challenge studies
Q. Are crustaceans from EU waters susceptible to WSSV?
Cumulative mortality of P. vannamei injected with edible crab innoculum
5
4
Mortality rate
3
2
control mortalities
1 Injected mortalities
Fed mortalities
0
1 2 3 4 5 6 7
Day
Injection, feeding
or bath exposure
to innoculum
prepared from Injection of filtered Mortality,
frozen WSSV- homogenate from WSSV histopathology,
infected shrimp exposure trial using TEM and WSSV
European species PCR of shrimp
recorded

7. Viral challenge studies – e.g. European lobster
WSSV-Infected cuticular epithelium of H.gammarus
• Experimental infection of European lobster (Homarus gammarus) via feeding
of WSSV-infected P. vannamei

8. Current work areas
Diseases in fisheries Diseases in aquaculture Transboundary movements
Immuno-competence toolbox Crustaceans as sentinels Pathogen systematics

9. Visit www.crustaceancrl.eu for information on our diagnostic remit and research programme