Following the introduction of PEDv to the US in 2013, feed was thought to be a potential contributor to the spread of the virus. This study evaluated if the spread of PEDv within feed manufacturing facilities could be controlled to reduce the threat to farms.

"We inoculated batches of feed with virus, and ran that up with a subsequent batch of flush feed, then we ran that with the initial PEDv negative feed," said Gebhardt. "We used PCR analysis as well as swine bioassay to determine if those samples did cause infection in naïve pigs."

Study results showed that manufacturing PEDv inoculated feed at feed mills generated a tremendous amount of dust. The dust moved throughout the facility and contained a large amount of virus.

"This study was one of the first to show that in an experimental setting when we collect dust following manufacturing PEDv positive feed and put that into naïve pigs, the dust can cause an infection," he said.

Another key take-away of the study was the use of rice hulls to flush feed manufacturing equipment following mixing PEDv positive feed is efficacious at reducing the amount of quantifiable RNA present within the feed manufacturing facility. Also, treating rice hull flushes with commercial formaldehyde or 10 per cent medium chain fatty acid blend is efficacious at reducing the infectivity of dust that's collected following feed manufacturing.

"It is very difficult to get the virus out of the feed manufacturing facility or feed mill once it enters. Therefore, it's important initially to keep it out, which means biosecurity principles are important," he said. "If it does get into the feed mill, we are developing procedures to potentially get it out of the feed manufacturing facility to ensure that no further animals get sick with the virus or any other biological contaminants."

To read Gebhardts' full research report, click here.

Further Reading

Learn more about biosecurity and diagnostic testing for swine coronavirus by clicking here.

For more information about swine diagnostics, click here or connect to the Thermo Fisher Scientific Swine Resource Center.