The purpose of this study was to quantify the rate of sow herds re-breaking with PED virus and evaluate the impact on performance. The study involved participants’ data from an existing program called the Swine Health Monitoring Project (SHMP). In this program, veterinarians enroll sow farms and report weekly change in health status for PEDv. Performance records were requested for those herds that experienced an outbreak before July 1, 2014.
From May 1/2013 through July 1, 2014, 474 / 1027 (46%) herds broke with PEDv. After July 1, 2014 through June 30, 2016, a herd that had a previous outbreak was approximately three times as likely to re-break as herds in our database that have never had an outbreak (23.8% vs 7.8%). This difference was statistically significant (p<0.001).
Prior to July 1, 2014, 474 herds were infected with PEDV. Of the 474 herds, 429 herds achieved the stable state of weaning PEDV PCR negative pigs, the median time was 28 weeks, ranging from 7 to 64 weeks. Performance data were made available from 190 herds to estimate the time required for the herd to recover back to the production level before the outbreak. A median of 2.7 piglets/inventoried sow were not weaned and the average time required to recover to baseline production was 10 weeks in 183 herds. Herd infected in quarters 3 or 4 of the year had approximately twice the negative impact. These data are valuable for veterinarians in advising clients on the anticipated impact and time to re-achieve a stable state with regards to PEDV.

Bob Morrison; BobM@UMN.Edu