Broilers are reared in an intensive production system starting with a small initial live weight that increases dramatically by the end of the production cycle. Within the broiler house there are consequent changes in heat, moisture and carbon dioxide production. Microbial decomposition of faeces and litter produces a number of aerial contaminants, particularly ammonia and dust as well as a complex of compounds responsible for the characteristic odour associated with these enterprises. The concentrationof most aerosol particles increases during the production period. Ammonia emissions from livestock buildings have considerable localised environmental effects when deposited on the adjacent land. High levels of inspirable dust can cause respiratory problems in broilers and the particles carry a proportion of the odorous volatile compounds that often attracts adverse comment by neighbouring residents.
