Relationship between feed quality and air quality in swine

. 20 samples of 2 commercial feedstuffs, one for fattening pigs and one for pregnant sows, half of them hammer mill ground and the others roller mill ground, were analysed in a study to determine the effect of milling and formulation on their mean particle size, standard deviation, apparent density, stability ratio and dust emission. Dust emission was measured in laboratory, for each sample, and distinguished in respirable and non respirable fraction. Type of formulation influenced the mean particle size, standard deviation, and apparent density and dust emission. The type of milling influenced significantly mean particle size, standard deviation and stability ration in the sow diet. Total dust emission was higher in hammer milled fattening pig diet and in roller mill sow diet. Inhalable dust was significantly higher in roller mill ground feedstuffs in both mixtures and in particular in pregnant sows diet, characterised by a great insertion of maize mill, for all the period of observation.