University of Minnesota Seeks Farms to Enroll in PRRS Virus Breeding Herd Stabilization Study

July 28, 2010 — Bob Morrison and Daniel Linhares

We are conducting a study entitled "Comparison of whole herd exposure programs as an aid in eliminating PRRS virus from sow herds", where the main goal is to compare methods of PRRS virus exposure following herd closure in regards to time needed to produce negative pigs (TTNP) at weaning.

PRRSV infected herds from United States of Canada that are planning to perform whole herd exposure and that fulfill the following criteria are eligible to participate in the study:

• farrow to wean sow herd
• diagnostic evidence that PRRS virus is present
• date of whole herd exposure is within 15 days of initiating herd closure
• herd owner agrees to collect and submit samples to the diagnostic laboratory and pay for the cost. As diagnostic support, the project will contribute $700 towards the cost.

A minimum of 10 blood samples collected monthly from the lightest male piglets from gilt litters due to be weaned beginning at 12 weeks after herd closure/virus exposure will be required. Samples will be pooled in groups of 5 and tested by PCR. When both pools (10 piglets) result negative to PCR, the next month 30 due to be weaned piglets will be sampled.

As part of the study we also request participants complete or update a PRRS risk assessment, to complete an individual herd enrollment form and to provide the sow-herd performance data from 52 weeks prior to the herd closure/virus exposure time and 52 weeks after the intervention.

Note: the information collected will only be used for the purpose of this study and it will be anonymous when presented in any form.

For further information, interested veterinarians please contact Daniel Linhares (612-625-2245, linha005@umn.edu) from the UMN. The investigators thank you for considering this request.