Power-washing and disinfecting rooms between pig groups are routine production practices. But, what exactly makes up the right program for your operation?

“Disinfection efficacy varies,” says Sandy Amass, DVM, PurdueUniversity. “There’s no single disinfectant that will work on every operation, nor is there one that will work on every pathogen. There is no best disinfectant.”

Diseases can easily transfer from previous pig groups occupying the same space. Leftover pathogens can lead to declining and uneven growth rates within the same pen of pigs.

“Thorough sanitation is the best method to minimize fomite contamination and reduce the likelihood that they will be the source of an infection,” adds Amass. For the record, fomites are objects such as clothing and equipment that can harbor disease agents and thereby transmit them.

The key is finding which detergent and disinfectant is right for your operation. The solution depends on your cleaning program’s goals and constraints – such things as water pH. It’s always wise to consult with your herd veterinarian and periodically review your program.

Here are a few considerations from Amass and Catherine Templeton, Synergy Services, Ontario, Canada when choosing a disinfectant:

  • Select a disinfectant with a label claim to address the pathogens that you want to control, as well as the physical conditions that you face. The label claim is based on laboratory tests (a.k.a. ideal conditions) illustrating that the disinfectant was able to kill certain pathogens. If there is no label claim, the only evidence that you have that the disinfectant might work is the word of the sales person, says Daniel Hurnik, health-management associate professor at the University of Prince Edward Island in Canada.

“Remember, just because the label claim says that a product is effective under laboratory conditions, doesn’t mean that the product will work in your operation,” adds Amass.

In the end, the best way to figure out your disinfectant needs is to try some of the disinfectants within your operation. It’s also wise to periodically review your product arsenal.

  • Calculate the correct amount of disinfectant to apply. The product monolog on the package will indicate the area that a certain amount of disinfectant is meant to cover.

Calculating the room or barn’s surface area is simple. Assume pen partitions and equipment are solid surfaces and add that area to the floor, ceiling and wall surface areas. This will give you the information you need to calculate how much product to apply.

  • Disinfectants should always be prepared and applied according to label directions.
  • Plan to use a biofilm removal agent at least once a year, especially if your water is hard or alkaline, says Hurnik.

Biofilm is a sticky, greasy film that’s hard to remove. For this task, it’s best to use a high-pressure washer. However, one downside of high pressure is creating an aerosol mist that can move throughout the room. If pigs are nearby, scrape out the manure and use a low-pressure wash instead, he notes.

Now that you’ve determined your disinfectant needs, here a few rules for cleaning and preparing your buildings:

  • Remove all organic matter. Regardless of which specific organism you’re trying to control, the most important step is removing organic matter from all surfaces and equipment.

Start by cleaning the room or building as soon as the pigs are moved out. Empty feeders and remove large amounts of manure. Then presoak the room. Shut off the ventilation system for the area or reduce airflow to a minimum during a 6- to 12-hour presoaking period. This will help retain moisture in the room or building, which will help soften surface residue. Be sure to restart

the ventilation system before you start the power-washing process.

Of course using hot water to presoak the room is most effective, as it will speed up the washing times. (For more information about hot- and cold-water comparisons, see “Are You Washed Up?” in the April 2006 issue of Pork.)

  • Washing times will vary by the room, its layout and how dirty it is,” says Hurnik. “For example, steel and plastic surfaces wash up faster than concrete so it’s hard to establish set times per room. Basically you wash until it’s clean.” (See Profit Tips, page 26, for information on time and cost comparisons.)

Disinfectants are generally most effectively applied through the low-pressure wand of a power-washer.

  • The size of the pressure-washer should match the job. For small rooms and hallways, a small washer will suffice. For large jobs, permanently installed industrial washers are more effective. Hurnik cautions that if you are using gas-powered washers indoors, you must ventilate the room to prevent carbon monoxide from accumulating.
  • Always provide protective clothing and equipment for the person doing the cleaning and disinfecting.

Once you have disinfected a room, you have two options. You can continue to use the disinfectant until a pathogen becomes a problem or you can test the equipment and other surfaces to see if the disinfectant actually killed the pathogen of interest.

Your veterinarian can help sample the environment for a specific pathogen. If there is residual disinfectant in the sample, you will need to neutralize it immediately. After sample collection, use a specialized media (DE broth or agar.) You or your veterinarian should contact the diagnostic laboratory prior to sampling the room to determine if there are specific needs.

All of these tips can help with your disinfection program, but it’s up to you to make sure you’re using the proper disinfectant for your operation. Remember, there isn’t one disinfectant that will work for every situation.

The Right Disinfectant for the Job

The following list outlines the different classes of compounds found in disinfectants, as well as descriptions and comments about them. Keep in mind, this may not be a complete list.

For more information on available disinfectants, go to the NationalBiosecurityResourceCenter’s Web site at www.biosecuritycenter.org, and click on “Disinfectant Search” located on the left side of the page.

Chlorine Based

  • Addresses bacteria and fungi.
  • Works best at pH 6 to 8; has poor residual activity; works poorly if organic debris is present.

Quaternary Ammonium

  • Germicide, fungicide, detergent.
  • As a group, it works best on Gram-plus bacteria, with some activity on viruses, fungi and Gram.
  • Effective at pH 6 to 8. Hard water reduces speed of kill; provides some activity in the presence of organic debris; offers some residual activity.


  • Disinfectant, germicide, fungicide, virucide, vapor phase.
  • Kills a wide range of organisms. Effective at a wide pH range; is not affected by hard water. It’s active among organic debris; provides residual activity.


  • Germicidal disinfectant.
  • Good bactericide, but less effective on other organisms. Effective at alkaline pH levels (above 7) not affected by hard water; active with organic debris; provides residual activity.

Iodine based

  • Most common as a skin or equipment sanitizer.
  • Kills a wide range of organisms. Effective at acid pH levels (below 7); not affected by hard water; not active when organic debris is present; provides some residual activity.

Oxidizing Agents

  • Glutaraldehyde and quaternary ammonium combined – combines properties of aldehydes and quaternary ammoniums.
  • Kills a wide range of organisms; effective at a wide pH range; is not affected by hard water.

Biofilm Removing Agents

  • Acidic cleaner to remove biofilm (biological material trapped in hard-water scale.)
  • A degreaser, which aids in biofilm removal.