Date Full Report Received


Date Abstract Report Received



Institution: ,
Primary Investigator:

With the recent development of porcine circovirus vaccines, porcine circovirus associated disease (PCVAD) has become less of a challenge for swine producers. However, much is unknown about the transmission of the virus from dam to offspring and the effects of viremia at birth on vaccine efficacy. We theorized that viremia at birth would lower vaccine efficacy as measured by growth rate of pigs from birth to 150 days of age. To test this assumption we identified litters that were viremic at birth and matched them with litters that were not virmeic at birth. Within each litter we vaccinated one half of the pigs with a commercial PCV2 vaccine according to label directions and followed the pigs to market. We found that pigs which were viremic at birth were heavier at 14, 84, and 154 days of age compared to non-viremic pigs. As expected vaccine improved weight gain at 154 days of age by 10.96 lbs, but not at other time points. There was no interaction detected between vaccination and viremia at birth meaning that vaccine improved weight gain the same amount regardless of the piglet’s infection status at birth. Not surprisingly sows that were viremic at 21 days prior to farrowing were 3.65 times more likely to have a viremic litter. Sow viremia at farrowing was not predictive of piglet infection status. Based on these data, viremia at birth does not influence vaccine efficacy or lifetime growth under the conditions of this study. Control of sow PCV2 infection is not likely to impact growing pig performance.