Aerosols in livestock production, including particulate matter, pathogens, microbes (i.e., endotoxins), and viruses are important to livestock health, disease transmission, worker health, and overall cost of production. As particulate matter is composed of organic substances it can absorb and contain gases, microorganisms (including viruses), and other agents that can enhance its biological activity and, therefore, increase the risk of health effects. A number of studies have shown high prevalence rates of respiratory illnesses in animal farmworkers due to particulate matter present in livestock production facility air. In addition, an outbreak within a herd can have devastating economic impacts on the farm and to the industry. According to the estimates made by the George Morris Centre, the Porcine Reproductive and Respiratory Syndrome (PRRS) is costing a minimum of 130 million dollars per year to the Canadian swine industry. Moreover, bacteria and viruses can be easily spread to other animals, as well as to human populations, during transport.
The reduction of particulate matter and microbes in livestock production are paramount to livestock health and productivity and to the health of those who work in these environments. A number of remedial techniques to control these contaminants in livestock barns have been reported. These techniques include oil spraying, modifying feeds, litter amendment, and exhaust air treatment. There are, however, few technologies currently available on the market for air quality control. Among these remedial technologies, the electrostatic precipitation (ESP) based technology has the potential to be a robust and economically viable technology to reduce airborne particulates and associated microbes and odour in animal buildings.
Electrostatic precipitators have been effectively used to remove fine particles in flue gases from industrial plants (e.g., power, cement, metal industries) for decades. Among the advantages of ESP are low-pressure drop, high gas capacity, low energy demand, and high collection efficiency for fine particles (> 99%). Despite its desirable characteristics, ESP application in removing particulate matter, odour, and microbes in livestock facilities, as well as its impacts on animal productivity, has not yet been fully explored and investigated. Preliminary laboratory and field studies, however, have demonstrated that ESP is capable of effectively reducing dust, gases, and bacteria in livestock barns.
Although the efficacy of ESP technology has already been investigated in a number of studies, its application in livestock production is still limited to the research stage. ESP efficacy in removing microbes in poultry barns has not yet been fully investigated and needs additional studies. Detailed economic analyses such as those that look into energy savings from reduced power requirements during winter and productivity gains from improved air quality against both ESP installation and operating costs are still lacking. Moreover, a remedy to the generation of ozone, which is a by-product from the ionization process, has not been considered in other previous related studies. Thus, the proposed research aims to evaluate the strategies (e.g., material type and configuration of charging electrodes, voltage level) in minimizing ozone production in larger scales such as in commercial poultry houses. More importantly, from industry perspectives, the Chicken Farmers of Saskatchewan (CFS) are interested in applying new techniques, such as ESP, to reduce dust and associated odour and microbes in poultry barns.
In the context of microbial deactivation/elimination, the current methods used in livestock facilities, including animal transport trailers, are disinfection with oxidizing agents (e.g., chlorine, formaldehyde, hydrogen peroxide), fogging with an organic acid, ultraviolet irradiation, and air filtration systems. However, drawbacks of these techniques are cost, odour, residual contamination, and toxicity. More recently, a chemical-free nano-technology-based method has been reported for foodborne bacteria inactivation. In this technique, engineered water nanostructures (EWNS) are generated through electrospraying condensed water vapour recovered from room air and has been found to be effective in inactivating bacteria due to the high electric charge per surface area at the nanoscale of the generated EWNS. This technique appears promising as a non-chemical method for microbial deactivation in livestock barns as water spray is also commonly used in these facilities for cooling animals and mitigating dust levels. However, this method has been tested only at lab-scales with foodborne bacteria and airborne transmitted pathogens. Thus, this project aims to evaluate the effectiveness of this method in deactivating microorganisms prevalent in livestock buildings and transport trailers.
Aims of the Project
The aims of this project:
- Reduce dust and microbes in livestock facilities, so as to reduce/eliminate risks and hazards and enhance health and safety in agricultural production.
- Improving and/or adapting existing technological advances for application in dust and microbial reduction in livestock facilities.
To achieve this project, the following objectives will be completed:
- Evaluate the efficiencies of ESP based air-cleaning techniques in removing dust in poultry houses in small, medium, and full-scale studies.
- Develop/adapt a nanospray-based technology in deactivating microbes in swine barns and investigate its potential application using a lab-scale electrospray.
- Evaluate the performance of electrospray in deactivating microbes in small and medium scale swine barns.
- Evaluate the performance of electrospray in deactivating microbes in swine transport trailers.
- Compare the results of ESP and nanospray studies to the results attained from the previously tested dust reduction strategies (i.e., oil sprinkling, v-scraper, and air treatment unit) to determine the most efficient, cost-effective, and feasible dust and microbial reduction method.
2019 - 2020 Year 1 Update
Aerosols in livestock production include dusts or particulate matter, pathogens, microbes and viruses all of which pose risks to both human, animal and rural community health. This research aims to evaluate the effectiveness of two emerging green technologies, electrostatic precipitation-based air cleaning technique and electro nano-spray, in dust reduction and deactivating microorganisms prevalent in livestock buildings and transport trailers.
During Year 1 of Activity 2, a pilot-scale electrostatic precipitator (ESP) study was conducted at the Poultry Research and Teaching Unit at the University of Saskatchewan. For the pilot-tests, 2,195 one-day-old chicks were randomly placed in one of two identical rooms - control or treatment - and raised under a floor housing system for 113 days. In the treatment room, commercially available electrostatic particle ionizers were used to remove dust, gases, and bacteria. In the control room, pullets (young chickens) were raised under typical conditions without the ESP. The results of these tests showed that the ESP-room had a 69% reduction in total dust, a 48% reduction in PM10 and a 44% reduction in PM2.5 as compared to the control room. Total bacteria count was also evaluated and the results showed a 33% reduction in bacteria at the beginning of the trial, but the reduction in bacterial concentration became less apparent with time.
To study the effects of nanospray, a laboratory-scale nanospray apparatus was developed. Preliminary tests on poultry barn bacteria showed up to 95% deactivation efficiency with the use of nanospray. Subsequent trials will be carried out in swine barns.
2020 - 2021 Year 2 Update
Year 2 was particularly busy for the research team with a multitude of experiments completed for both the ESP and Nanospray technologies.
The ESP system was tested in a medium-scale facility at the Research and Development Institute for the Agri-Environment (IRDA, Québec) as well as in a large-scale study at the Poultry Centre of the University of Saskatchewan. The small-scale ESP study that was initially planned was abandoned as it was considered unnecessary with the preliminary trials conducted at the Poultry Centre prior to the official start of the project. The medium and large-scale studies evaluated the efficiency of the technology in reducing dust, bacteria, ammonia (NH3), and odour in broiler houses as well as its impact on animal health and productivity.
The experimental trials demonstrated that the ESP system could substantially reduce dust in broiler houses by up to 62%, bacteria by up to 63%, and odour by up to 50%. However, no considerable reduction was observed on the NH3 concentration and performance decreased over time, probably due to the high accumulation of dust on collection surfaces. No substantial impact was observed on animal mortality or on the feed conversion ratio.
The research team completed two lab-scale studies demonstrating the performance of the nanospray system for 1) decontaminating surfaces and 2) inactivating airborne bacteria. The EWNS were produced with a lab-scale nanospray system using a syringe pump to force a water-based solution through metallic needles connected to a high voltage power supply. Very high inactivation rates, up to a 4.0 log reduction (99.99 % efficiency), were obtained in the surface tests using small stainless-steel coupons inoculated with a solution of E. coli.
A 250 L acrylic chamber with a controlled airflow was then used for the tests with airborne bacteria. Good results were obtained for the deactivation efficiency, but the values were much lower than with the surface decontamination tests. Since the EWNS droplets fell through the contaminated air as it flowed across the acrylic chamber, contact between the microbes and EWNS was not as efficient as with the surface tests.
2021 - 2022 Year 3 Update
Experimental trials for the ESP system were completed in Year 2 for both the medium and large-scale facilities. Results demonstrated that this technology could substantially reduce dust, bacteria, and odour in broiler houses. Work in Year 3 consisted of analysing data and communicating results.
For the EWNS, the lab-scale tests were completed in Year 2, therefore Year 3 activities focused mainly on optimizing the pilot-scale electro-nanospray system for generating the EWNS during the tests in a real barn environment (small-scale pig rooms at the Prairie Swine Centre barn facility) that will be conducted in Year 4. Both the air flow rate through the treatment chamber housing the nanospray and the number of nanospray injector needles had to be optimized for the pilot-scale system. The optimization studies used Escherichia coli as the test pathogen. Airborne E. coli inside the treatment chamber was generated with a nebulizer and used to evaluate the inactivation efficiency of the EWNS injected with 4, 8, 16 or 32 needles at various chamber air flow rates. Using experimental data, data from the literature and mass balance equations, the highest E. coli reduction was obtained at a chamber air flow rate of 41 L/min (10 ACH) and a nanospray with 16 needles. The results obtained will be applied in the subsequent small-scale tests in the PSC barn facility.
Other than the experimental work in the lab, the research team was also prolific with regards to sharing their findings, a total of 4 scientific research papers were published in Year 3!
2022 - 2023 Year 4 Update
2023 -2024 Year 5 Update
Si, Y., Yang, Y., Martel, M., Zhang, L., Kirychuk, S., Predicala, B. & Guo H. 2021. Characterization of Electrical Current and Liquid Droplets Deposition Area in a Capillary Electrospray. Results in Engineering, 9, 100206.
Si, Y., Yang, Y., Martel, M., Thompson, B., Predicala, B., Guo, H., Zhang, L., & Kirychuk, S. 2021. Effects of operating parameters on the efficacy of engineered water nanostructures (EWNS) in inactivating Escherichia coli on stainless-steel surfaces. Transactions of the ASABE, 6(46), 1913–1920.
Yang, Y., Martel, M. C., Thompson, B. N., Guo, H., Predicala, B. Z., Zhang, L., & Kirychuk, S. P. 2021. Characterisation of engineered water nanostructures (EWNS) and evaluation of their efficacy in inactivating Escherichia coli at conditions relevant to livestock operations. Biosystems Engineering, 212, 431–441.
Si, J., Kirychuk, S., Yang, Y., Martel, M., Thompson, B., Zhang, L., Predicala, B., & Guo, H. 2022. Research Note: Evaluation of the efficacy of engineered water nanostructures in inactivating airborne bacteria in poultry houses. Poultry Science, 101(2), 101580.
Yang, Y., Kirychuk, S., Si, Y., Martel, M., Guo, H., Predicala, B., & Zhang, L. 2022. Reduction of airborne particulate matter from pig and poultry rearing facilities using engineered water nanostructures. Biosystems Engineering, 218,1-9.
Bartlett, K.H., Bittman, S., and Chipperfield, K. 2012. Efficacy of electrostatic space charge system (ESCS) to reduce the environmental impact of organic particulate matter from chicken broiler production barns in the Fraser Valley, BC. American Journal of Respiratory and Critical Care Medicine 185: A3228.
Bonifait, L., Veillette, M., Létourneau, V., Grenier, D., and Duchaine, C. 2014. Detection of Streptococcus suis in bioaerosols of swine confinement buildings. Applied and Environmental Microbiology 80(11): 3296-3304.
Brauer, H. and Varma, Y.B.G. 2012. Air Pollution Equipment. Springer-Verlag, Heidelberg, Germany.
Cambra‐Lopez, M., Winkel, A., van Harn, J., Ogink, N.W.M., and Aarnink, A.J.A. 2009. Ionization for reducing particulate matter emissions from poultry houses. Transactions of the ASABE 52(5):1757-1771.
Dee, S., Pitkin, A., Otake, S., and Deen, J. 2011. A four-year summary of air filtration system efficacy for preventing airborne spread of porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae. Journal of Swine Health and Production 19(5): 292-294.
Hao, X.X., Li, B.M., Zhang, Q., Lin, B.Z., Ge, L.P., Wang, C.Y. and Cao, W. 2013. Disinfection effectiveness of slightly acidic electrolysed water in swine barns. Journal of Applied Microbiology 115: 703-710.
Jerez, S.B., Mukhtar, S., Faulkner, W., Casey, K.D., Borhan, M.S., and Smith, R.A. 2013. Evaluation of electrostatic particle ionization and biocurtain™ technologies to reduce air pollutants from broiler houses. Applied Engineering in Agriculture 29(6): 975-984.
Kirkham, L. 2013. Statistical modelling of PM10 and PM2.5 exposures in poultry barns, and evaluation of electrostatic precipitators to control particulate emissions. Presented at the 23rd Conference on Epidemiology in Occupational Health EPICOH 2013: Improving the Impact June 18–21, 2013, Utrecht, The Netherlands.
Kirychuk, S.P., Reynolds, S.J., Koehncke, N.K., Lawson, J., Willson, P., Senthilselvan, A., Marciniuk, D., Classen, H.L., Crowe, T., Just, N., Schneberger, D., and Dosman, J.A. 2010. Endotoxin and dust at respirable and nonrespirable particle sizes are not consistent between cage- and floor-housed poultry operations. Annals of Occupational Hygiene 54(7): 824-832.
Lau, A.K., Vizcarra, A.T., Lo, K.V., and Luymes, J. 1996. Recirculation of filtered air in pig barns. Canadian Agricultural Engineering 38(4): 297-304.
Lim, T.T., Wang, C., Heber, A.J., Ni, J.-Q., Zhao, L., and Hanni, S.M. 2008. Effects of electrostatic space charge system on particulate matter emission from high-rise layer barn. ASABE Annual International Meeting, Paper Number 085143, Providence, Rhode Island, June 29-July 2, 2008.
Manitoba Agriculture. 2017. Agriculture disinfection of swine barns. Available at: http://www.gov.mb.ca/agriculture/livestock/production/pork/print,disinfection-of-swine-barns.html [Accessed 18 August 2017].
Manyi-Loh, C.E., Mamphweli, S.N., Meyer, E.L., Makaka, G., Simon, M., and Okoh, A.I. 2016. An overview of the control of bacterial pathogens in cattle manure. International Journal of Environmental Research and Public Health 13: 843-869.
Mitchell, B.W., Richardson, L.J., Wilson, J.L., and Hofacre, C.L. 2004. Application of an electrostatic space charge system for dust, ammonia, and pathogen reduction in a broiler breeder house. Applied Engineering in Agriculture 20(1): 87-93.
Mussell, A. 2010. RRS costs Canadian swine industry 130 million dollars per year. Available at http://www.farmscape.ca/f2ShowScript.aspx?i=23527&q=PRRS+Costs+Canadian+Swine+Industry+130+Million+Dollars+Per+Year [Accessed 30 Aug. 2017].
Pyrgiotakis, G., McDevitt, J., Bordini, A., Diaz, E., Molina, R., Watson, C., Deloid, G., Lenard, S., Fix, N., Mizuyama, Y., Yamauchi, T., Brain, J., and Demokritou, P. 2014. A chemical free, nanotechnology based method for airborne bacterial inactivation using engineered water nanostructures. Environmental Science Nano 1: 15-26.
Pyrgiotakis, G., McDevitt, J., Yamauchi, T., and Demokritou, P. 2012. A novel method for bacterial inactivation using electrosprayed water nanostructures. Journal of Nanoparticle Research 14: 1027-1037.
Pyrgiotakis, G., Vasanthakumar, A., Gao, Y., Eleftheriadou, M., Toledo, E., DeAraujo, A., McDevitt, J., Han, T., Mainelis, G., Mitchell, R., and Demokritou, P. 2015. Inactivation of foodborne microorganism using engineered water nanostructure (EWNS). Environmental Science & Technology 49: 3737-3745.
Rimac, D., Macan, J., Varnai, V.M., Vucemilom M., Matkovic, K., Prester, L., Orct, T., Trosic, I., and Pavicic, I. 2010. Exposure to poultry dust and health effects in poultry workers: impact of mould and mite allergens. Int. Arch. Occup. Environ. Health 83:9-19.
Sobsey, M.D., Khatib, L.A., Hill, V.R., Alocilja, E., and Pillai, S. Pathogens in animal wastes and the impacts of waste management practices on their survival, transport and fate. 2006. Animal Agriculture and the Environment: National Center for Manure and Animal Waste Management. J.M. Rice, D.F. Caldwell, and F.J. Humenik (eds.), pp. 609-666, Pub. Number 913C0306. St. Joseph, Michigan: ASABE.
Stein, H., Schulz, J., Kemper, N., Tichy, A., Krauss, I., Knecht, C., and Hennig-Pauka, I. 2016. Fogging low concentrated organic acid in a fattening pig unit – Effect on animal health and microclimate. Annals of Agricultural and Environmental Medicine 23(4): 581-586.
St. George, S.D. and Feddes, J.J.R. 1995. Removal of airborne swine dust by electrostatic precipitation. Canadian Agricultural Engineering 37(2):103-107.
Tanaka, A. and Zhang, Y. 1996. Final report: Efficiency of a negative ionization system on dust settling in a confinement swine building. Agriculture Development Fund.
Viegas, S., Faisca, V. M., Dias, H., Clerigo, A, Carolino, E., and Viegas, C. 2013. Occupational exposure to poultry dust and effects on the respiratory system in workers. Journal of Toxicology and Environmental Health, Part A: Current Issues 76(4-5): 230-239.
Yan, K. 2009. Electrostatic Precipitation: 11th International Conference on Electrostatic Precipitation. Zhejiang University Press, Hangzhou, China and Springer-Verlag, Heidelberg, Germany.