Reduction of microbial contamination on the surfaces of layer houses using slightly acidic electrolyzed water

Abstract

The objective of this study was to evaluate the effectiveness of slightly acidic electrolyzed water (SAEW) in reducing pathogens on pure cultures and on cotton fabric surfaces in the presence of organic matter and estimate its efficacy in comparison with povidone iodine solution for reducing pathogenic microorganisms on internal surfaces of layer houses. Pure cultures of E.coli, S.enteritidis, and S.aureus and cotton fabric surfaces inoculated with these strains were treated with SAEW in the presence of bovine serum albumin (BSA). In the absence of BSA, complete inactivation of all strains in pure cultures and on cotton fabric surfaces was observed after 2.5 and 5 min treatment with SAEW at 40 mg/L of available chlorine concentration (ACC), respectively. The bactericidal efficiency of SAEW increased with increasing ACC, but decreased with increasing BSA concentration. Then, the surfaces of the layer houses were sprayed with SAEW at 60, 80, and 100 mg/L of ACC and povidone iodine using the automated disinfection system at a rate of 110 mL/m(2), respectively. Samples from the floor, wall, feed trough, and egg conveyor belt surfaces were collected with sterile cotton swabs before and after spraying disinfection. Compared to tap water, SAEW and povidone iodine significantly reduced microbial populations on each surface of the layer houses. SAEW with 80 or 100 mg/L of ACC showed significantly higher efficacy than povidone iodine for total aerobic bacteria, staphylococci, coliforms, or yeasts and moulds on the floor and feed trough surfaces (P< 0.05). SAEW was more effective than povidone iodine at reducing total aerobic bacteria, coliforms, and yeasts and moulds on the wall surface. Additionally, SAEW had similar bactericidal activity with povidone iodine on the surface of the egg conveyor belt. Results suggest that SAEW exerts a higher or equivalent bactericidal efficiency for the surfaces compared to povidone iodine, and it may be used as an effective alternative for reducing microbial contamination on surfaces in layer houses.

Electrolyzed water and its application in animal houses

“…Scientists have given various names to EW with a pH of 5.0-6.5, but none of these names has been universally adopted. Most studies have defined EW with a pH of 5.0-6.5 as SAEW [1][2][3]15,28,33, . However, it has also been called electrolyzed neutral water [58] , near-neutral electrolyzed oxidizing water [25,59] and NEW [24,48,60,61] .…”

“…The environment within animal houses is often contaminated with pathogenic microorganisms and contaminated surfaces in such facilities may act as reservoirs for pathogenic microorganisms [1][2][3] . Exposure to high levels of airborne microbes in animal houses can have negative impacts on the health of both the animals and the workers [4][5][6][7] .…”

“…For these reasons, SAEW and NEW may be alternative disinfectants for decontamination in animal houses. A considerable number of studies have reported the increased use of SAEW and NEW for controlling contamination in animal houses, including facilities for swine, poultry and diary [1][2][3]15,[31][32][33][34][35] . This review covers some important aspects of SAEW/NEW, including definition, generation, microorganism inactivation and applications in animal houses.…”

Microbicidal effects of slightly acidic hypochlorous acid water and weakly acidified chlorous acid water on foulbrood pathogens

“…SAHAW is a chlorine-based disinfectant produced by the electrolysis of dilute hydrochloric acid solution in the electrolytic cell without a separating membrane and is permitted as a food additive by the Ministry of Health, Labour and Welfare (MHLW) of Japan. The principal ingredient of SAHAW with pH values of 5.0-6.5 is hypochlorous acid (HClO), which exhibits a wide spectrum of antimicrobial activity [19,22,25,28]. As SAHAW has strong antimicrobial activity with a relatively low available chlorine concentration (ACC), it has the advantage of being less corrosive for equipment, less irritating for the human body [13,14,19] and having less of an impact on the environment.…”

“…As SAHAW has strong antimicrobial activity with a relatively low available chlorine concentration (ACC), it has the advantage of being less corrosive for equipment, less irritating for the human body [13,14,19] and having less of an impact on the environment. However, in the presence of organic matter, its antimicrobial activity is known to decrease [22].…”