Temporal and spatial distributions of aerial contaminants in an enclosed pig building in winter.

Abstract

Optimal management of indoor air quality in an enclosed swine house, especially in winter, is indispensable for preventing the transmission of infectious respiratory disease to workers and animals. Studies are needed to elucidate the correlation of aerial contaminants and climate factors. It was observed that indoor air contamination in an enclosed pig building was the highest at 2:00--5:00 PM, followed by 8:00--11:00 PM and 8:00--11:00 AM. It was assumed that this was attributed to the increase of swine activities in the afternoon. In general, the concentration of total dust and total airborne bacteria in an enclosed pig building was found to have a significant correlation with temperature and relative humidity (P<0.05). There were significant correlations between total dust and total airborne bacteria, between total dust and ammonia, and between total dust and odor at the 95% confidence level. In conclusion, temperature and total dust concentration correlated significantly with all parameters except hydrogen sulfide (H(2)S). This could have been due to the drying of swine feces due to the increase in interior temperature and the resuspension of feed deposited on the floor of the pig building by the swines' activity, resulting in a high generation of dust that adsorbed and carried the airborne bacteria and odorous compounds in the enclosed pig building. It was proved that an adsorptive capacity of dust for ammonia was higher than for hydrogen sulfide.