The effect of air filtration on air hygiene and pig performance in early-weaner accommodation

Abstract

ABSTRACT The effects of an internal recirculating air filter on air hygiene and pig performance were studied using two groups each of 100 early-weaned pigs from a commercial herd. The two groups were housed in separate rooms under identical conditions except that one room contained a recirculating air filter. Five trials were carried out, but the same records were not kept in all trials. The air throughput of the filter was similar to the installed ventilation capacity (0·9 m 3 /s). The filter material nominally removed particles > 5 μm. Distribution ducts discharged the filtered air downwards over the pigs' lying area at a velocity of 0·3 m/s. At locations close to the pigs, the most representative proportional reductions of total particles, dust mass, and bacterial colony-forming particles were 0·58 ( P < 0·01), 0·73 ( P < 0·01), and 0·51 ( P < 0·01), respectively. No differences in growth rate or health of pigs after 3 to 4 weeks were observed between the rooms but the pigs originating from the room containing the air filter reached a marketable state 6 to 8 days earlier than the control group pigs on the three occasions that this aspect was monitored ( P < 0·0·01).