POMS the latest R&D Results - Kube et al
- 1. POMS – The Latest R&D Results Shellfish Futures, Adventure Bay, Tasmania. 2 October 2013
- 2. Pacific Oyster Mortality Syndrome POMS Ostreid herpesvirus (OsHV-1uvar) France 2007-8 New Zealand 2010 Georges River 2010 Sydney Harbour 2011 Hawkesbury River 2013
- 3. Mooney Marra Mullet Ck Coba Porto DAY 0: DAY 1: DAY 3: DAY 8: First sighting (30% mortality on one lease) By afternoon mass mortality 10 million dead oysters Entire system affected
- 4. The R&D Response 1. Genetic selection for resistance 2. Develop a laboratory infection model system 3. Epidemiology and husbandry practices to reduce economic losses
- 5. Three things you need to know about breeding for resistance to Pacific oyster mortality syndrome Peter Kube (CSIRO) Mike Dove (NSW DPI) Matthew Cunningham (ASI) Paul Hick (NSW DPI) Wayne O’Connor (NSW DPI) Peter Kirkland (NSW DPI) Nick Elliott (CSIRO)
- 6. POINT #1: There is good genetic variation for POMS resistance in our population
- 7. FIELD CHALLENGE NOV 2012 JUVENILES (AGE 12 MONTHS)
- 8. FIELD CHALLENGE NOV 2012 AT INPUT
- 9. Woolooware Bay, Georges River (24 May 2012) Genetics trial University of Sydney trial
- 12. SURVIVAL AT 14 DAYS = 0%
- 15. POINT #2: The better your data the better the genetic progress
- 16. Difficult to get a good field challenge TRIAL DATE ANIMALS DATA Trial 1 Apr 2011 Adults No mortality Trial 2 Apr 2012 Spat 50% mortality – perfect Trial 3 Nov 2012 Juveniles 80% mortality – marginal Trial 4.1 Mar 2013 Spat 100 % mortality – failure Trial 4.2 Apr 2013 Spat 10% mortality – marginal
- 17. Good data = good genetic values
- 18. Good data = good genetic values
- 19. POINT #3: Selective breeding can provide a fix but not an instant fix
- 22. Expected genetic change Best families mid 2014
- 23. Expected genetic change Best families mid 2015
- 24. Expected genetic change Best families mid 2016
- 25. A laboratory model for infection of Pacific oysters with Ostried herpesvirus type-1 (OsHV-1) Paul Hick, Mike Dove, Wayne O’Connor, Xingnian Gu, Andrew Read, Peter Kirkland
- 26. Elizabeth Macarthur Agricultural Institute
- 27. GOAL: Develop procedures to infect oysters with OsHV-1 • OsHV-1 has been isolated from oyster tissues (original Georges R outbreak) • Used to infect disease free oysters • Developed procedures for long term storage (including cryopreservation) • Ongoing use of the same, well characterised isolate is possible
- 28. Successful infection of spat by immersion • • • Adding virus to water was sufficient to infect and kill spat (effective in 3 separate trials including with cryopreserved OsHV-1) Variable results for juveniles and work is ongoing Work has started on a challenge for larvae Immersion challenges preferred because: • closer to natural infection compared to injection • Only practical way of managing large numbers of individuals
- 29. Ongoing work: – Determine long-term stability of cryopreserved OsHV-1 – Define difference in susceptibility with age more closely – Assess repeatability of laboratory infection model – Apply laboratory challenge in genetic resistance project
- 30. Husbandry practices to reduce OsHV-1 mortality of Pacific oysters Crassostrea gigas First steps towards integrated management within an infected estuary Ika Paul-Pont, Olivia Evans, Navneet Dhand, Ana Rubio, Richard Whittington Faculty of Veterinary Science – The University of Sydney
- 31. Field trials – Georges River Height experiment in trays: summers 2011/2012 2012/2013 Standard growing height Better survival? Immersion time Exposure to virus Higher growing height +300mm Woolooware Bay, Georges River, NSW > Triploid PO 11-12 month old: Reduction of mortality by 25-50% Maximum mortality at high height : 30-50% > Triploid PO 2-7 month old: No significant reduction of mortality Low Cumulative mortality (%) Results: 50% High
- 32. Window of infection – Georges and Hawkesbury Rivers Every two weeks: 12 000 spat deployed at 8 sites Spat collected, replaced by a new batch Growth/mortality rates + PCR testing for OsHV-1 (n=30-100 spat per site) Botany Bay - Georges River 2011/2012: November – May 2012/2013: November – May Site A Broken Bay - Hawkesbury River 2012/2013: January – May Marra Marra Creek Mullet Creek Site B Site C Patonga Kimmerikong Porto Bay
- 33. Safe spat experiment - 2013 March 2013: Land based experiment installed on-shore adjacent to the Hawkesbury River Development of safe rearing techniques (farmers and hatcheries) Specific water treatments to prevent disease occurrence Co-funding: Tasmanian Oyster Research Committee n=2000 spat/treatment Flow rate= 5L/min/tank No food supply Daily sampling / mortality check
- 34. Safe spat experiment - 2013 Mortality 100% Control (107 –109 viral DNA copies/g) Sampling collection (n=40 per treatment) and PCR testing Cumulative mortality (%) River (104 –108 viral DNA copies/g) 80% 60% Chiller (107 –108 viral DNA copies/g) 40% Sedimentation 20% No virus detected UV+filtration No virus detected 0% 6-Apr 10-Apr 14-Apr 18-Apr 22-Apr Date 26-Apr 30-Apr 4-May 8-May 12-May Conclusions: - water treatments and land based system allowed spat survival in an infected estuary - the role of UV and filtration remains unclear and need to be tested separately - the 48h sedimentation provided the best outcome (cheap, easy) but needs to be confirmed
- 35. What can R&D deliver in the medium term? 1. A medium term solution is expected from a combination of resistant stock and changed husbandry practices 2. A laboratory infectivity model will be available and will be an essential tool for breeding, and other, work 3. Useful levels of resistance are expected in juveniles by mid 2016 (three more years of selection) 4. Given the time required for commercial scale-up, this stock won’t be available until 2018 at the earliest (as diploid)
- 36. Project Staff and Acknowledgements NSW DPI Mike Dove Paul Hick Peter Kirkland Wayne O’Connor Xingnian Gu Andrew Read FUNDING ASSISTANCE Oysters Australia Seafood CRC FRDC CSIRO Peter Kube Nick Elliott ASI Matthew Cunningham University of Sydney Ika Paul-Pont Olivia Evans Navneet Dhand Ana Rubio Richard Whittington FIELD SITE (Georges River) Drakes Oysters