WORLD PORK EXPO: New Tools, Strategies Discussed against PED Virus06 June 2014
US - A news conference was held at the World Pork Expo this week, offering new insights into porcine epidemic diarrhoea (PED), which has been affecting the pig industry in the US for the past year. Jackie Linden reports.
In a conference entitled 'PEDv is Speaking: Are We Listening?' Boehringer Ingelheim Vetmedica Inc. invited leading pig veterinarians, researchers and disease pathologists to provide an update on PED, recent industry collaborations, research efforts, diagnostic and management tools and field observations on the impact of the disease in Midwest production systems.
Introduced by Dr Greg Cline, Technical Manager for Enteric Products with BIVI, Dr Phil Gauger opened the proceedings by outlining the development of PED virus in North America over the last year.
Having outlined the progress of the disease so far, Dr Gauger of the Molecular Diagnostics Section at Iowa State University, described the challenges involved in the control of the virus.
On prevention and control of the virus, he said that effective methods of control are inconsistent and success with controlled exposure is variable.
Additional vaccines are urgently needed as few vaccines are currently available, he said.
On virus transmission, PED virus continues to infect and re-infect pig populations. Effective biosecurity is required to prevent transmission,
Dr Gauger added that diagnostic tests are needed to measure the protective immune response and to understand better the duration of exposure in exposed or immunised animals.
Several important questions regarding PED remain unanswered, he said, including how the virus entered the US, the pathological differences between the original and new variants of PEDv and the most effective biosecurity measures.
For the prevention and control of PED, Dr Gauger said that the industry needs:
- additional, effective vaccines
- further serological/diagnostic tests
- cell culture isolates of both the original and variant forms of the virus for experimental challenge testing, such as vaccine testing
- identify correlates of immune function, and
- experimental studies on the pathogenesis and immunology.
In response to a question about the prospects of a vaccine against PED, Dr Gauger said that vaccination has shown some success and that several companies are developing new vaccines but the process is slow. Controlled feed-back, he added appears not to be effective for long-term protection.
Economic Cost of PED
Taking the reduction in piglet survival as a key parameter to assess the costs to the US pig industry of PED, losses are estimated at 6.9 million pigs to May 2014, according to Dr Dale Poulson of BIVI.
These figure are based on a survey of 84 farms by BIVI. On each farm, the range in sows affected varies from five to 100 per cent, and annual production losses were between zero and 13 per cent.
A total of 3.4 million sows are estimated to have been affected nationally so far, or 57 per cent of the national sow herd.
PED prevalence seems to be waning since January-February 2014, said Dr Poulson.
He went on to explain the new PEDv tracking and information service available to industry through a collaboration with the University of California-Davis and Iowa State University.
Also addressing the meeting were Dr Erin Johnson of BIVI and Dr Noel Garbes of Bethany Swine Management Services. Their presentations on Area Regional Control of pig diseases will be covered in a separate report.