#04-187

Complete

Date Full Report Received

06/18/2007

Date Abstract Report Received

06/18/2007

Investigation

Institution:
Primary Investigator:

As stated in the contract, we require a lay interpretation of the project, suitable for public release by the Board. Please include contact information, should the public want to contact you directly. PRRS virus seems to move relatively slowly in a population. Although pigs that already have the virus on arrival to the nursery will become PRRS positive (seroconvert) sooner than those who don’t, most pigs in a group with virus circulation will seroconvert by 8 weeks post weaning (late nursery or early finishing). Infection with PRRS does seem to have an impact on growth of the pigs even when no clinical signs of disease may be present. Pig end weights were significantly different between pigs that seroconvert and those that did not (242 lbs at 150 days from enrollment compared to 206 lbs at 143 days). We are modeling these data to estimate financial impact. Clearly these differences further support efforts to prevent PRRSV infection of herds but they also suggest that within farm factors that delay or prevent spread of the virus may positively improve individual pig performance and group averages.