The Pig Site Backroom
I have been browsing through this website on PMWS with interest and have been especially interested in the "case histories" on PMWS-affected farms. My sympathies lie with pig farmers who have to cope with this severe disease problem. However, I note that comments have been made on the "lack of progress in understanding and controlling this diseases".
For the record, we at DARDNI, Belfast have been working on PMWS and PCV2 since 1997 with colleagues in USA, Canada and Europe. Indeed, we were the first laboratory in the world to isolate and characterise the causal agent of PMWS in 1997 ie PCV2. This was prior to the introduction of the severe disease in UK. We were not surprised when the disease "took off" in England and predicted its spread thought the UK some time ago.
Significant progress has been made in Belfast, however unfortunately we have been unable to work directly to any great degree with UK farmers, veterinarians or fellow researchers.
We have had defined diagnostics for the disease since 1998, a disease model in SPF pigs using a PCV2 inoculum since 1999 and now a good understanding of the disease process. We are currently co-ordinating an EU-funded project on PCV2 and PMWS.
Recent work has shown that inoculation of 4-7 week-old colostrum-fed and colostrum-deprived pigs with purified PCV2 preparations can results in up to a 50% death rate if the inoculates immune system is activated. This has now been demonstrated with 4 separate compounds (3 commercial pig products) in experimental and field conditions (KLH +ICFA, commercial vaccine, commercial para-vaccine and commercial cytokine preps). Put simply, it is now clear that PCV2 is not a new virus and PMWS is not a new disease (cases have been identified in Spain and elsewhere from the mid 1980s).
PCV2 + IMMUNOSTIMULATION IN CONVENTIONAL PIGS = PMWS.
Other interesting results from field investigations by ourselves and colleagues in Italy and Holland indicate that good passive transfer of maternal antibody to PCV2 to piglets protects against PMWS, but not infection with PCV2. High humoral antibody levels to PCV2 in sows and gilts appear to be protective.
Our work in Belfast on development of a vaccine continues for PMWS and perhaps PDNS. Indeed it is a high priority area of R and D for us and we continue to collaborate with colleagues in Italy, Spain,Denmark, Canada, USA, Holland and France.We would welcome the opportunity to participate in field work with colleagues in the UK.
Dr Gordon Allan
Department of Agriculture and Rural Development for N Ireland (DARDNI)
If you would like to make comment on any of Dr Allan's findings, Click Here to go to the discussion zone and select the Message "PCV2 and PMWS - Significant progress made in Belfast"