Cold plasma technology to clean swine barn air

Porcine reproductive and respiratory syndrome virus (PRRSv) costs the US swine industry more than $580 million each year. First described in North Carolina, Iowa, and Minnesota in the late 1980s, the virus rapidly spreads through swine barns and is one of the industry’s biggest game changers. Additionally, pigs infected with virulent strains exhales aerosols containing a large quantity of the virus.

Today, researchers in the Veterinary Diagnostic Lab at the CVM are looking to apply research they are doing on decontaminating foods in collaboration with the University of Minnesota College of Science and Engineering (CSE) to swine barn air filtration in an effort to further promote swine health and safety in the food industry at large.

Plasma, served cold

Plasma is defined as partially or fully ionized gases with neutral net charge. It consists of a cocktail of photons, ions, free radicals, molecules, and atoms—many of which are highly reactive, which allows for many applications, including water decontamination. Plasma sources can also be engineered to produce plasma at close to room temperature—often referred to as cold plasma—enabling the treatment of highly heat-sensitive surfaces, such as some foods.

2D- integrated coaxial micro hollow dielectric barrier plasma discharge array
Plasma (purple) is produced inside the holes of the array, through which air is blown. Pathogens are inactivated when they come into contact with the air coming through the holes in the array.

The United States Department of Agriculture is supporting Sagar Goyal, PhD, professor in the Department of Veterinary Population Medicine at the CVM; Peter Bruggeman, PhD, professor of Mechanical Engineering at the CSE; and their team of researchers in pursuing the use of cold atmospheric gaseous plasma technology for decontaminating food and food-processing surfaces.

The team is seeing success in the lab—bacteria and viruses stand little chance against the cold plasma they are making.

According to Goyal, the laboratory results look extremely promising. “If a surface is contaminated with viruses or bacteria, we can kill them,” says Goyal. “If food is contaminated—as early as during harvest by food handlers—our goal is to use cold plasma to kill the contaminants.”

A pig impact

“Meanwhile,” says Goyal, “swine farmers are already using air filtration systems to mitigate disease. But these are not foolproof, so if we can combine them with this cold plasma, it would be helpful in getting rid of any disease affecting swine that can be transferred by air.” This includes, but is not limited to, PRRSv. So, cold plasma could positively impact the food and agricultural industry in more ways than one.

Follow the link to read more about how cold plasma could be used in swine barns.

Science Page: Sow Herd Filter Study

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 note from Dr. Cesar Corzo who is starting a study on sow herd filtration and recruiting herds. The MSHMP mission goes beyond collecting data regarding swine herd disease status, it also includes research projects that are relevant to the swine community.

Objectives of the study

The objectives of the study are to describe the occurrence of PRRSv in the filtered sow herd population within MSHMP and to assess the associations between farm-level factors and the introduction of PRRSv into filtered sow herds. The results of the study may guide practitioners and veterinarians to modify their management and biosecurity practices in filtered sow herds.

Who can enroll?

All filtered sow herds of MSHMP participants will be eligible for the study. The database will be used together with the PRRSv incidence measure to understand occurrence of PRRS before and after filters were installed. A survey has been created to collect farm specific data such as:

  • Date when herd was filtered
  • Type of ventilation (negative or positive)
  • Back draft prevention methodology
  • Type of pre-filter and filter
  • Pre-filter and filter replacement frequency
  • Number of barns and load outs
  • Audit frequency
  • Frequency of gilt introduction and weaning events
  • Regional density

If you are interested in participating, please contact Dr. Cesar Corzo at corzo(at)umn.edu

Science page: Evaluation of positive pressure filtration to reduce aerosol transmission of PRRSV during an experimental challenge of farm access points

This is our Friday rubric: every week a new Science Page from the Swine Health Monitoring Project. The previous editions of the science page are available on our website.

Key points from this week edition:

  • Dilute vaccine aerosolization combined with novel environmental sampling techniques allowed for testing of PRRSV aerosol entry into Positive Pressure Filtration (PPF) farm access points.
  • Under the experimental conditions of this study, positive pressure air speeds >1.85m/s resulted in no aerosol transmission.
  • Ensuring adequate positive pressure air speed through steps taken to increase access point pressure can further reduce the risk of aerosol PRRSV transmission on PPF farms.

The full report on positive pressure filtration and PRRSV transmission via aerosols is available.