Airborne bacterial reduction by spraying slightly acidic electrolyzed water in a laying-hen house

Figures & data

Figure 1. Longitudinal section view of the laying-hen house. Airborne bacterial measurements were performed at points A, B, and C to compare bacterial reductions by spraying disinfectants. Air temperature and relative humidity were measured at point B and outside of the building.

Figure 2. Cross-section view of the laying-hen house. Airborne bacterial measurements were performed at points A, B, and C to compare bacterial reductions by spraying disinfectants. Air temperature and relative humidity were measured at point B and outside of the building.

Table 1. Disinfectants used in the experiment

Disinfectant	Chemical Agent	Active Compound Concentration (mg L^−1)
Diluted DDAB	Didecyl dimethyl	167^a
	ammonium bromide	333^a
		500^a
SAEW	Available chlorine	156 ± 5^b
		206 ± 11^b
		262 ± 12^b
Notes: ^aCalculated from the active compound concentration given by the manufacturer and different dilution factors. ^bMean ± deviation of 4 measurements (n = 4).

Figure 3. Air temperature outdoors and indoors during the test period. Vertical bars represent means ± standard errors.

Table 2. Experimental treatments in the laying-hen house

Treatment	Disinfectant	Active Compound Concentration (mg L^−1)	Spraying Volume (mL m^−2)
Treatment 1	Diluted DDAB	167^a	120
Treatment 2	Diluted DDAB	333^a	120
Treatment 3	Diluted DDAB	500^a	120
Treatment 4	Diluted DDAB	333^a	90
Treatment 5	SAEW	156 ± 5^b	120
Treatment 6	SAEW	206 ± 11^b	120
Treatment 7	SAEW	262 ± 12^b	120
Treatment 8	SAEW	262 ± 12^b	90
Notes: ^aCalculated from the active compound concentration given by the manufacturer and different dilution factors. ^bMean ± deviation of 4 measurements (n = 4).

Figure 4. Relative humidity outdoors and indoors during the test period. Vertical bars represent means ± standard errors.

Figure 5. Airborne bacterial concentration variations in the control, treatment 1, and treatment 5. Spraying diluted DDAB (167 mg L⁻¹) and SAEW (156 mg L⁻¹) were administrated starting at 11:00 a.m. in the amount of 120 mL m⁻² in treatment 1 and treatment 5, respectively. No spraying was carried out in the control. Vertical bars respect means ± standard deviations with n = 12 (3 sampling points each day, 4 sampling days).

Figure 6. Airborne bacterial concentration variations in treatment 1, treatment 2, treatment 3, and treatment 4. Spraying diluted DDAB (167, 333, and 500 mg L⁻¹) in the amount of 120 mL m⁻² and spraying diluted DDAB (333 mg L⁻¹) in the amount of 90 mL m⁻² were administrated starting at 11:00 a.m. in treatment 1, treatment 2, treatment 3, and treatment 4, respectively. Vertical bars respect means ± standard deviations with n = 12 (3 sampling points each day, 4 sampling days).

Figure 7. Airborne bacterial concentration variations in treatment 5, treatment 6, treatment 7, and treatment 8. Spraying SAEW (156, 206, and 262 mg L⁻¹) in the amount of 120 mL m⁻² and spraying SAEW (262 mg L⁻¹) in the amount of 90 mL m⁻² were administrated starting at 11:00 a.m. in treatment 5, treatment 6, treatment 7, and treatment 8, respectively. Vertical bars respect means ± standard deviations with n = 12 (3 sampling points each day, 4 sampling days).