Books - Non-fiction

CAWTHRON INSTITUTE REPORT NO AUGUST PDF

Description
REPORT NO STUDIES ON OSTREID HERPES VIRUS 1: A CAUSAL AGENT IMPLICATED IN SUMMER MORTALITY IN THE OYSTER CRASSOSTREA GIGAS BY PCR OF ARCHIVAL HISTOLOGY SPECIMENS 1 STUDIES ON OSTREID HERPES VIRUS
Published
of 13
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
REPORT NO STUDIES ON OSTREID HERPES VIRUS 1: A CAUSAL AGENT IMPLICATED IN SUMMER MORTALITY IN THE OYSTER CRASSOSTREA GIGAS BY PCR OF ARCHIVAL HISTOLOGY SPECIMENS 1 STUDIES ON OSTREID HERPES VIRUS 1: A CAUSAL AGENT IMPLICATED IN SUMMER MORTALITY IN THE OYSTER CRASSOSTREA GIGAS BY PCR OF ARCHIVAL HISTOLOGY SPECIMENS STEVE WEBB Final report: Year 2 this report is available for public release International Mobility Fund Activity Report on IMF Programme Dd U11-05 Commencement date 17 December 2010 Duration of funded collaboration Until 10 June 2012; extended to 1 August 2012 Funding provided: Year 1 $4, August 2011 Year 2 $4, June 2012; extended to 1 August 2012 NZ Principal Investigator: Principal Collaborator: Dr Steve Webb Senior Scientist, Aquaculture Pathology Cawthron Institute, Nelson, New Zealand Dr Tristan C Renault Head of the Genetics and Pathology Laboratory Laboratoire de Génétique et Pathologie (LGP) Institut Français de Recherche pour l Exploitation de la Mer (IFREMER) La Tremblade, France CAWTHRON INSTITUTE 98 Halifax Street East, Nelson 7010 Private Bag 2, Nelson 7042 New Zealand Ph Fax REVIEWED BY: Kevin Heasman APPROVED FOR RELEASE BY: Robert Matheson ISSUE DATE: 31 July 2012 RECOMMENDED CITATION: Webb S Studies on ostreid herpes virus-1: a causal agent implicated in summer mortality in the oyster Crassostrea gigas by PCR of archival histological specimens. Prepared for Royal Society of New Zealand. Cawthron Report No p COPYRIGHT: Apart from any fair dealing for the purpose of study, research, criticism, or review, as permitted under the Copyright Act, this publication must not be reproduced in whole or in part without the written permission of the Copyright Holder, who, unless other authorship is cited in the text or acknowledgements, is the commissioner of the report. I confirm that the grant provided was expended only on the costs associated with my IMF contract Dd U Signed: Steve Webb Date: 25 July 2012 TABLE OF CONTENTS 1. INTRODUCTION PROJECT AND ACTIVITY REPORT SEMINARS/ WORKSHOPS BENEFITS PUBLICATION INTENTIONS INTERNATIONAL OPPORTUNITIES INTERNATIONAL RECOGNITION MAINSTREAM FUNDING FUTURE COLLABORATION HIGHLIGHTS APPENDIX... 5 vii 1. INTRODUCTION The Dumont d Urville International Mobility Fund has, for the last two years, supported joint New Zealand/French work on the ostreid herpes virus-1 (OsHV-1). Details of the projected work are provided in Webb (2011). Full citations to this and any subsequent works mentioned here in the text are cited in the current report under Section 5 Publication Intentions. The project focused on the development of assays and the detection and characterisation of the ostreid herpes virus 1. End-point PCR and QPCR methods have been developed and employed to detect OsHV-1 infections in fresh and paraffin-embedded archival histology specimens of the Pacific oyster Crassostrea gigas and other bivalve species. The specimens were from French mortality events with known involvement of OsHV-1 and oysters sampled from mortality events in New Zealand to which no cause has yet been ascribed. 2. PROJECT AND ACTIVITY REPORT As previously reported (Webb 2011), we successfully adapted PCR methods from end-point PCR to QPCR and used them in our study of a range of oyster specimens including fresh, alcohol-preserved and paraffin-embedded tissue samples of the Pacific oyster Crassostrea gigas. In addition, we also used the PCR primers C2/C6, ORF37, IA1/IA2 CF/CR, ORF38, 37 TER F/R, ORF 36, ORF 37. Successful detection of OsHV-1 and differential results with these primers and sequencing allowed us to infer genetic differences in geographic strains of the virus these are reported in Renault et al (2012). Further work on paraffin-embedded oyster tissue samples was restricted to New Zealand material as (in contrast to New Zealand) the French principal collaborator already had an extensive archive of DNA previously extracted from fresh material. It also became clear in the course of the work that when there is a choice between paraffin and fresh material for DNA extraction, the latter is always preferred as DNA quality and quantity is generally better. Nevertheless, being able to use paraffin specimens is a great advantage, as this makes available a large resource of archival material in New Zealand for which no previous DNA analysis has been done. The results of last year s work are summarised in Renault et al (2012). We found that the New Zealand virus appears to be a single strain with close affinities to the socalled OsHV-1 µvar - a particular strain of the ostreid herpes virus that has been implicated in severe mortalities in several countries. Preliminary PCR assays on 2012 New Zealand oysters indicate that they too have a virus closely related to OsHV-1 µvar. Further sequencing is required before firm conclusions can be drawn about the fine-scale affinities of the New Zealand virus. Full details of these findings will be published in the proposed paper mentioned in Section 5. 1 AUGUST 2012 REPORT NO CAWTHRON INSTITUTE The second visit by the New Zealand principal investigator (PI) to IFREMER in June 2012 extended previous work on DNA purified from fresh and archival fixed paraffin embedded material - OsHV-1 positives were detected in both types of sample. A consequence of the raised profile gained by Cawthron was the visit by a European Union (EU)-funded researcher who set up the method for In situ hybridisation (ISH). Results are detailed in publications mentioned in Section 5 of this report. In this year s assays of fresh Crassostrea gigas material, 16 samples out of 47 were OsHV-1 positive. In paraffin Crassostrea gigas archival samples 3 out of 9 were OsHV-1 positive. Proposed work mentioned in the last report (Webb 2011) was completed in samples of sand clams Paphies subtriangulata, Spisula aequilatera and Mactra sp. were assayed for OsHV-1 and found negative. Work is continuing to sequence the successful amplifications and we intend to publish the results as mentioned in Section SEMINARS/ WORKSHOPS A seminar titled Molluscan pathology in New Zealand) was delivered on Wednesday 5 th July 2012 at Centro de Investigaciones Marinas (CIMA), Spain. 4. BENEFITS Advantage to French researcher The French researcher has further access to New Zealand oyster specimens from routine and mortality samplings. In addition, the New Zealand PI has again demonstrated the efficacy of assaying DNA extracted from formalin-fixed paraffinembedded archival material. The French researcher has benefited from the Cawthrondevised OHVDFor-OHVDRev OsHV-1 primers and has used them in internationally published studies. A further extension of the current French study on geographic variation of the OsHV-1 was facilitated by the New Zealand PI s subsequent visit to a Swedish oyster hatchery where specimens were taken and sent to IFREMER for analysis. Advantages to New Zealand This visit and the subsidiary trips made possible by the Dumont d Urville International Mobility Fund has, by conferring greater New Zealand pathology capability, enhanced our ability to support exporters of New Zealand aquaculture products to overseas markets. We now have a better diagnostic capability in the event of disease outbreaks and have improved methods to assess and establish the health status of our shellfish. Direct access to expertise in the latest methods will benefit the New Zealand industry IFREMER can help us in these aims, not least because it is a European reference laboratory for molluscan pathogens, and it has expressed interest in collaborating with a New Zealand-based investigator in continuing to work on relevant parasite species in New Zealand molluscs. Other benefits include: Raised international profile ( See Section 7) Scientific publications (See Section 5) Greater understanding about the OsHV-1 oyster disease New collaborators (See Section 6) 5. PUBLICATION INTENTIONS In addition to the works below, we also expect to publish on the OsHV-1 detection and characterisation findings this year. Renault T, Moreau P, Faury N, Pepin J-F, Segarra A, Webb S Phylogenetic analysis of clinical ostreid herpesvirus 1 (Malacoherpesviridae) isolates using amplified fragments from three virus genome areas. Journal of Virology 86: López Sanmartín M, Webb S 2012 (In Preparation). In-situ hybridation for detection and localisation of ostreid herpes virus (OsHV-1) in oyster histological sections. Cawthron Report, 9pp. Webb SC Studies on ostreid herpes virus 1: a causal agent implicated in summer mortality in the oyster Crassostrea gigas, by PCR of archival histology specimens. Prepared for the Royal Society of New Zealand. Cawthron Report No pp. 6. INTERNATIONAL OPPORTUNITIES New collaborators Dr Antonio Villalba, (CIMA), Spain. Exchange of shellfish pathology information and study materials, supply of EU-funded post-doctoral researchers to work on pathology issues of mutual interest such as bivalve with infections Chlamydia, rickettsiae and Perkinsus. Dr. Alyssa Joyce, Tjärnö Marine Biological Laboratory, Sweden. Joint applicant for Swedish-funded research on oyster pathology. Karljohan Smedman and Kent Berntsson Ostrea Sverige AB, Sweden. Further work for this hatchery to address disease issues. Monserrat López Sanmartín IFAPA, Spain. Setting up ISH at Cawthron. Further work could include the localisation of OsHV-1 activity in infected oyster tissues. 3 AUGUST 2012 REPORT NO CAWTHRON INSTITUTE Dr Susana Darriba Couñgo, Spain. Exchange of shellfish pathology information and study materials, laboratory harmonisation and establishment of Quality Assurance protocols. 7. INTERNATIONAL RECOGNITION Three examples below show that the collaboration has contributed to the promotion of New Zealand as a centre for innovation: Publications coming from this project. By being available in Europe and by having a raised scientific profile I was invited to an expenses-paid visit to Ostrea Sverige AB, Sydkoster, West Sweden to advise about disease investigation. The seminar delivered on Wednesday 5 rd July at Centro de Investigaciones Marinas (CIMA), Spain generated interest and has shown that we, in New Zealand, have a significant pathology resource that can make a useful contribution to their work. 8. MAINSTREAM FUNDING The internationally-published results from the work will provide further leverage when bidding for funding. Funding bid with Dr. Alyssa Joyce (in preparation) for research on oyster pathology. The Royal Swedish Academy of Sciences, funding to support internationalisation and scientific renewal at the Sven Lovén Centre for Marine Sciences. Ongoing collaboration with IFREMER will enhance our scientific quality and therefore facilitate publication of work done at Cawthron. The support of expertise available at IFREMER will add credibility to future bids in the field of shellfish pathology. 9. FUTURE COLLABORATION Ongoing work with Dr Tristan Renault and his institute to chart the spatial and temporal variation in OsHV-1, its host specificity and virulence. During the visit, opportunity was taken to discuss other fields of study with a view to extending collaboration to work on other important molluscan pathogens. Please see Section 6 for details of prospective future collaborations. 10. HIGHLIGHTS The project has led to several new collaborations: see Section 6. Support from the Dumont d Urville International Mobility Fund, and previous similar New Zealand government funds, have allowed the development of expertise in a New Zealand researcher such that this expertise is recognised internationally, resulting in an invitation to visit and provide pathology advice to a Swedish oyster hatchery. My raised profile also resulted in an EU-funded researcher requesting to work in Cawthron under my guidance. The results are described in López San Martín M, Webb S (2012, In Preparation). 11. APPENDIX Collaborators Contact Details Dr Antonio Villalba Centro de Investigaciones Marinas (CIMA) Conselleria do Medio Rural e do Mar Xunta de Galicia Aptdo.13 Vilanova de Arousa, Spain Dr. Alyssa Joyce Tjärnö Marine Biological Laboratory Department of Marine Ecology Gothenburg University Strömstad , Sweden Karljohan Smedman (Managing Director and Member of the Board) Dr Kent Berntsson (Hatchery Manager) Ostrea Sverige AB Sydkoster, West Sweden Monserrat López Sanmartín IFAPA, Centro Agua del Pino Crta. El Rompido-Punta Umbría, Km Cartaya, Huelva Spain Dr Susana Darriba Couñgo Head of pathology unit (INTECMAR) Xunta de Galicia Vilanova de Arousa 36611, Spain 5
Search
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks
SAVE OUR EARTH

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!

x