Cleaning and disinfection on pig farms

Breaking the cycle of reinfection on-farm is important when faced with infectious diseases such as swine dysentery or salmonella. An effective way to do this is with a consistently high standard of cleaning and disinfection (C&D).

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This should be achievable however standards are often allowed to slip and bad habits creep in. Use this information to make sure your C&D efforts keep infectious diseases at bay. 

Cleaning and disinfection: The basics

A C&D plan should form a major part of your veterinary health plan and should be carried out conscientiously.

Producers have known for a long time that buildings can become ‘pig sick’ and continued use can bring about a steady decline in health and performance.

When pigs are met with a high level of infection, they react with an immune response. This response causes growth checks – reducing growth rates and increasing days to slaughter.

The five basic steps of cleaning and disinfection are:

  1. Remove organic matter
  2. Use a detergent
  3. Clean
  4. Dry
  5. Disinfect

The efficacy of disinfectants depends on several factors, including:

  • Cleaning/removal of organic matter – Organic matter deactivates disinfectants.
  • Ambient temperature – Proper C&D techniques are especially important in cold temperatures, for example the Porcine Reproductive and Respiratory Syndrome (PRRS) virus can survive and remain infectious for over a week at 4°C.
  • Contact time – A longer contact time can, in some cases, enhance the efficacy of disinfectants.
  • Pathogen – Use pathogen-specific disinfectants where possible; some pathogens are more susceptible to some disinfectants than others.

The information below should be used to create your own farm's C&D plan, which will feed into your veterinary health plan.

Removing infection

  • Remove organic waste, e.g. bedding, muck, feed residue and dust.
  • Resist the temptation to keep back any ‘clean’ straw for reuse – it is a reservoir for infection.
  • Material below the slats should also be removed; if this is not possible, ensure levels remain at least 30 cm below floor surfaces and that material cannot leak or overflow.
  • Take out moveable items, e.g. feeders, drinkers, enrichment, cleaning tools, and clean and disinfect separately.

Remember to isolate electrics

  • Clean and disinfect the water system (including the header tank and filters) using a recommended product.

Nipple drinkers can become blocked during this process. Check before putting new pigs into the building

Using detergent

  • Do not miss this stage out. A wide range of common pathogens show poor response to disinfectants under high organic load, as the organic matter deactivates the disinfectant.
  • A thorough hot pressure wash is not enough to break down the oily biofilm that can protect bacteria from disinfectants. Only a detergent can do this.
  • Detergent improves the efficiency of the washing/cleaning and reduce the time needed for pressure washing.
  • Soak all surfaces (ceiling, walls, floors and any fixed equipment) with cold water and apply a farm-specific detergent under low pressure; alternatively, use a foam or gel cleaner.
  • Soak for at least 30 minutes (preferably longer, e.g. overnight).

How to clean

  • Work from top to bottom (ceiling to walls to floors). This avoids any splashing of previously cleaned areas with dirty water.
  • Pay attention to out-of-sight and hard-to-reach spots, e.g. fan and ventilation ducts, on top of pipes, light fittings.
  • Pressure wash with hot (70ºC or above), clean water. If your pressure washer does not have a hot water option, consider buying one that does.
  • Ensure all surfaces and equipment are visibly clean.
  • Make sure dirty water drains away freely without contaminating other areas.
  • Repair or replace corroded fixtures, surfaces and flooring, as these can harbour germs.
  • Any equipment that cannot be pressure washed, such as creep lamps, must be cleaned by hand.
  • Allow rooms to dry before applying disinfectant.

Using disinfectant

  • Choose a disinfectant that is suitable for the range of diseases present on your unit; discuss this with your vet. Use Defra’s helpful list of approved disinfectants.
  • Make sure you and your staff understand the safety information and take appropriate steps for safe use and disposal of disinfectant.
  • Ensure all the necessary protective clothing is worn.
  • Make up fresh quantities of disinfectant solution daily and check staff know how to make up the correct concentrations. Be aware that dilution rates can vary with ambient temperature.
  • Make sure the disinfectant is compatible with the detergent as well as the microorganisms you are targeting.
  • Check that it is appropriate for use, for example one for the pens/building may not be suitable for the water system.
  • Disinfectant is usually best applied evenly, under low pressure (e.g. with a knapsack sprayer), until all surfaces are saturated.
  • Move methodically through the room/building, paying attention to corners, out-of-sight and hard-to-reach areas.

Avoiding recontamination

  • Plan the C&D so that there is no need to re-enter the cleaned building/pen before restocking. It takes time and effort to clean and disinfect properly – make sure you don’t undo all your good work!
  • Place newly replenished foot dips and brushes outside the clean rooms/buildings. Ensure dips are replenished with suitable disinfectant as soon as they look dirty and at least on a weekly basis regardless of appearance.
  • Regularly clean/replace the boot brushes/washers as they can become heavily contaminated.
  • Wash and disinfect all equipment (e.g. brushes, weigh crate, moving boards, scrapers) between batches, this is frequently overlooked but crucial to prevent recontamination.
  • Launder overalls and clean boots frequently; never enter cleaned and disinfected facilities wearing dirty protective wear.

Chemicals checklist

  • Are all chemicals stored and handled as directed?
  • Are all chemicals still within the expiration date? This is important as after the expiry date, the product might not work.
  • Is the person mixing the chemicals trained/competent?
  • Is the person mixing chemicals using suitable personal protective equipment (e.g. goggles)?
  • Are the disinfectants Defra-approved?
  • Are the disinfectants used at General Orders concentration? Incorrect doses are ineffective.
  • Is the disinfectant being mixed in a tank, rather than by using a metering device?
  • Have you selected the right product for the job? See table below.
Type of product Best for...
Chlorocresol-based Boot dips
Glutaraldehyde-based Surface cleaning
Hydrogen peroxide/
peracetic acid-based
Cleaning water lines

Buildings checklist

  • Has all equipment been removed before cleaning? This includes feeders, drinkers and partitions.
  • Has all visible debris been removed? Organic matter (muck) blocks the disinfectant, meaning there is less of it to work against the bacteria.
  • If you're using a detergent-wash programme and disinfectant, be sure to use products that have a similar pH. The pH can normally be found on the product label.
  • Have you considered continuous sanitisation of water (even if mains water is used)? Water lines and drinkers on pig units can become contaminated with a range of bacteria that can cause intestinal infections.
  • Have you remembered to clean and disinfect walkways, races or other equipment, such as trolleys, transporters or weighers, used by the pigs during movement between buildings?

Vehicles checklist

  • Have you ensured all vehicles are sprayed with a fast-acting disinfectant product?
  • Have you paid special attention to wheel arches and pipes of feed lorries?
  • Are you cleaning and disinfecting scrapers daily? Avoid using the same scraper between different groups of pigs.
  • Do you have a separate scraper for each building? If this is not possible, scrape from younger pigs to older and deal with any groups of sick pigs last.