Although visual inspection is a commonly used tool in the industry to assess farrowing room cleanliness after cleaning and disinfection, visual inspection is often insufficient to confirm the absence of pathogens and reduce disease transmission risk. In a study funded by the Swine Health Information Center and led by Dustin Boler at Carthage Innovative Swine Solutions, adenosine triphosphate (ATP) bioluminescence technology was investigated as an objective diagnostic tool for producers to ensure farrowing room cleanliness. Across five farrowing crate locations and the room entry floor testing, the areas of highest concern were the sow feeder and the entryway floor as detected by both ATP bioluminescence and bacterial coliform plate counts (CPC). Overall, this study confirmed that ATP bioluminescence technology can be used as a monitoring tool for ensuring farrowing room cleanliness and identified the highest risk areas in the farrowing room for contamination.
Find the industry summary of the project, SHIC 24-001, here using the search feature.
Pig producers have adopted cleaning procedures and biosecurity practices to ensure farrowing rooms are free of infectious organisms before the next group of sows are introduced. However, there is a need for objective pen-side diagnostic tools that can assist in confirming cleanliness. ATP bioluminescence has been used in other industries to provide real-time feedback on surface cleanliness through the detection of ATP from organic sources.
The goals of this project were to 1) determine the areas of the farrowing crate with the greatest surface contamination risks, 2) determine the correlation between microbial counts and relative light units (RLUs) as detected by ATP bioluminescence, and 3) identify the number of farrowing crate locations needed to accurately determine surface cleanliness. Traditional monitoring methods (bacterial culture, qPCR, and virus isolation) were compared to the novel ATP bioluminescence technology.
For this study, samples were collected between April and May 2024 at a 5600-sow commercial farm in western Illinois. The sow farm had recently completed a PRRSV and Mycoplasma elimination program but was experiencing frequent rotavirus outbreaks during the sampling period. The designated sow farm weaned approximately 200 litters of pigs each week and each litter averaged 12.5 weaned pigs per sow. Each farrowing room consisted of four rows of 14 crates each for a total of 56 crates per room. Approximately four farrowing rooms were washed every week.
Cleaning procedures followed farm standard operating procedure for farrowing room sanitation. Farrowing rooms were scraped to remove manure from the alleyways and farrowing crates. After most of the manure was scraped into the pit, farrowing rooms were power washed with a commercial pressure washer by farm personnel with fresh hot water set at 3000 pounds per square inch to remove any residual material. The farrowing room was then visually inspected while still wet. The room was disinfected using accelerated hydrogen peroxide at a dilution of 1:64 after it was visually determined to be clean by farm personnel.
Five crates within each room and the entryway floor were swabbed for ATP testing. Swabs were collected from six locations, including the entryway floor to the farrowing room and five areas within each crate: 1) sow feeder, 2) sorting bars, 3) back wall, 4) corners, and 5) piglet floor mat. Swab samples were collected across a total of 21 rooms and 105 crates during the study. Twelve of the 21 rooms were sampled early in the week (Sunday, Monday, or Tuesday) and nine of the 21 rooms were sampled late in the week (Thursday, Friday, or Saturday). Additionally, 13 farrowing rooms of the 21 sampled for ATP bioluminescence were randomly selected and swabbed in the same locations for CPC to determine total colony forming units. A total of 337 environmental swabs were collected during the project. However, only 305 were included in the statistical analyses due to large variability in cleanliness outcomes that resulted in CPC values that exceeded the quantifiable threshold for the procedure.
Three ATP luminometers (Charm Sciences novaLUM II-X, 3M Clean Trace, and Neogen AccuPoint) were used to evaluate real-time testing capabilities, determine variability of RTUs within a crate and across luminometers, and estimate the relationship between ATP bioluminescence and CPC. Bacterial loads were quantified by colony forming units/100cm2 (CFM) with higher CFM indicating increased levels of bacterial contamination. The percentage of samples above 105.5 CFU/100cm2 was greatest for the entryway floor (93.8%) followed by the sow feeder (93.1%), sorting bars (49.5%), back wall (13.8%), piglet floor mat (11.8%), and corners (10.5%). This ranking gives an indication of highest risk areas in a farrowing room for bacterial contamination and cleaning needs.
Overall, this study demonstrates that ATP luminometers are a novel tool for producers to use, in conjunction with CPC testing, to objectively assess farrowing room cleanliness on-farm. The areas of greatest risk for contamination were the entryway floor and the sow feeder as indicated by both ATP bioluminescence and CPC. These results agree with previous studies showing the sow feeder is difficult to effectively clean after washing and disinfection. Entryways are a sanitation risk but may not represent room cleanliness due to constant worker foot traffic entering and exiting the room. Specifically targeting the sow feeder and piglet sorting bars for additional cleaning and disinfection would be beneficial to reducing risk and ensuring farrowing house cleanliness.
The Swine Health Information Center, launched in 2015 with Pork Checkoff funding, protects and enhances the health of the US swine herd by minimizing the impact of emerging disease threats through preparedness, coordinated communications, global disease monitoring, analysis of swine health data, and targeted research investments. As a conduit of information and research, SHIC encourages sharing of its publications and research. Forward, reprint, and quote SHIC material freely. For more information, visit http://www.swinehealth.org or contact Dr. Megan Niederwerder at mniederwerder@swinehealth.org or Dr. Lisa Becton at lbecton@swinehealth.org.
Contributed by Dr. Megan Niederwerder, Executive Director, Swine Health Information Center