This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.
This week, we are sharing a study done by Taylor Homann, a DVM student at the University of Minnesota in collaboration with the Swine Vet Center and Boehringer Ingelheim, regarding the comparison of several sample types to detect PRRS and flu by PCR.
- Pooling oral fluid samples seems to be a good strategy to determine the status of a farm (positive/negative) for influenza A virus (IAV) and PRRSV.
- Sampling water cups using environmental Swiffer™ samples appears to be a sensitive approach to detect IAV at the pen level.
- However, sample size has been limited to one farm.
The objective of this project was to compare the sensitivity of pooled pen oral fluids (OF) and environmental samples (Swiffer™ kits on water cups) using individual pen oral fluids as the standard.
Fifteen paired environmental and individual pen OF were collected at days 3, 7, 10, 17, 24 and 31 post placement in two different nursery farms. Environmental samples (ES) were taken using Swiffer™ cloths to sample the bottom of water cups (both pans and bowls), focusing around nipples. After individual samples were collected, pen OF were pooled by 3.
There was an overall sensitivity of 71% (IAV) and 14% (PRRS) for the ES samples compared to individual OF. Pooled oral fluids samples had an overall sensitivity of 50%(IAV)and 80%(PRRSV)relative to individual pen OF.
In summary, ES appears to be a good strategy when sampling for IAV and not a reliable option when trying to diagnose PRRSV.