Aphanomycosis of crayfish: crayfish plague Item Type monograph Authors Alderman, D.J. Publisher CEFAS Download date 07/10/2021 02:10:36 Link to Item http://hdl.handle.net/1834/27243 Environm ent A g e n c y CRAYFISH PHASE 1 APHANOMYCOSIS OF CRAYFISH: CRAYFISH PLAGUE Research and Developm ent Technical report W 2-064 Figure 1 From the “Fischereibuch” of Emperor Maximillian I., 1499. R&D TECHNICAL REPORT W2-064 Aphanomycosis of Crayfish: Crayfish Plague A Report Prepared for The Environment Agency and English Nature R&D Technical Report W2-064 D.J. Alderman Centre for Environment, Fisheries and Aquaculture Science, Weymouth Laboratory R&D TECHNICAL REPORT W2-064 ( i i i ) R&D TECHNICAL REPORT W2-064 ( iv) Table of Contents 1. Summary..............................!..................................................................................................................1 PART I: LITERATURE OVERVIEW................................................ ...........................................................3 2. Introduction................................................................................................................ ............................5 3. Historical Overview................................................................................................................................ 6 3.1 Crayfish Plague in Europe post 1945............................................................................................6 3.2 Crayfish Plague in England and Wales........................................................................................13 4. Routes of transmission......... ..................................................................................................... ........ 23 4.1 Crayfish as carriers................................................................................................................... 23 4.2 Non Crayfish Routes of Transmission........................................................ ................................27 4.2.1 Equipment: angling gear, nets, rods and boots................................... ..................................27 4.2.2 Transmission on other animals.................................................................... ........................... 28 4.2.3 Effects of weirs on transmission of A. astaci......... ............................................................... 28 5. Disinfection and Control................................................................................... ................................... 29 6. Attempts to restock plague affected waters........................................................................................34 7. Diagnosis.............. .............................................................................................................................. 35 7.1 Diagnostic Procedures..................... ............................................................................................35 7.1.1 Standard screening methods for Crayfish Plague: Isolation o f A. astaci................... ......... 35 7.1.2 Presumptive Diagnostic Methods for Crayfish Plague............................................................37 7.1.3 Confirmatory Diagnostic Methods for Crayfish Plague..........................................................37 7.1.4 Molecular biological diagnostic methods for Crayfish Plague: status.......... ........................37 8. Taxonomy, Morphology and Physiology of A. astaci......................................................................... 41 8.1 Saprolegniaceae............................................................................................................................41 8.1.1 Identification to genus...............................................................................................................41 8.1.2 Identification at species level...................................................................................................42 8.2.Aphanomyces astaci morphology.................................................................................................42 8.3 A. astaci physiology................................................................................. ............... .....................43 9. Pathogenicity.........................................................................................................................................49 10. Pathology.............................................................................................................................................. 57 10.1 Behavioural Effects.......................................................................................................... .............57 10.2Gross Pathology............................................................................................................................57 10.3Microscopical observations on fresh preparations................................... ..................................58 10.4Histopathology............................................................................................................ ...................58 11 .Other diseases......................................................................................................................................63 11.1 Other fungi..................................................................................................................................... 63 11.1.1 Aphanomyces spp......................................................................................................... ...........63 11.1.2 Saprolegnia sp...........................................................................................................................63 11.1.3 Fusariumspp............................................................................................................................. 63 11.2Porcelain disease................................................................................................................... ......63 11.3Psorospermium haekeli.................................................................................................................64 11. 4Branchiobdellids............................................................................................................................64 PART II SPECIFICATION FOR FURTHER WORK AND OUTLINE EXPERIMENTAL DESIGNS 67 12.Backgroun d .................................................................................................................. 69 12.1Can fish movements results in the transfer of crayfish plague?............................ ................... 72 12.2Risks offish movements from sites of uncertain status..............................................................72 12.3Potential diagnostic methods........................................................................................................ 73 13..Risk reduction..................................................................................................................................... 77 13.1Transport Water.................................................... ........................................................................ 77 13.2Water and Fish.................................................. ............................................................................77 13.3Use of veterinary medicines......................................................................................... ...............78 14.Recommendations: diagnostic methods.............................................................................................. 80 15.Recommendations: risk reduction and fish movements............................................. .................. 81 References....................................................................................................................................................83 Appendix 1 Crayfish Plague in Europe, 1870 to 1945....................................................................... 89 Appendix 3 Crayfish Species..................................................................................................................108 Appendix 4 Supplementary Reference List............................................................................. ........ 112 R&D TECHNICAL REPORT W2-064 (v) Table of Figures Figure 1 From the “Fischereibuch" of Emperor Maximillian I., 1499............................................ ....... ............. ii Figure 2 Post World War II extension of crayfish plague to the Iberian Peninsula......... .................................8 Figure 3 Continues to spread in Spain in 1970s..................................................................... ....................... ..9 Figure 4 First reports in England, 1981......................................................................... .................................... 10 Figure 5 By 1995 infects UK, Greece and Turkey.............. ................................................. .............................11 Figure 6 Major outbreaks of crayfish plague in new areas since 1945...................... ............. .........................12 Figure 7 Bristol Avon and Rib (red)...................................................................................................................14 Figure 8 Confirmed and extended in Bristol Avon and Lee, R. Blackwater probable (purple)........................ 15 Figure 9 R Wey infected................................................................. .....................................................................16