Ammonia Concentrations and Emissions from Finishing Pigs Reared in Different Growing Rooms

Even with the adoption of Best Available Techniques (BAT) standards, pig producers have observed different degrees of fouling on the floor during the finishing phase. These differences depend on the excretory behavior of pigs reared in different growing facilities. Our objectives in this study were to measure ammonia (NH3 ) concentrations and emissions from finishing pigs reared in different growing rooms and subsequently housed in identical BAT room types. The 1600 pigs used in the study were reared in growing rooms with a slatted floor and a vacuum system for manure removal (WSF) or in growing rooms with a solid floor and an outside alley and storage pit (WCF). Pigs were grouped by type of growing room and allocated to two WCF finishing rooms per group. Mean NH3 concentration (7.45 vs. 5.31 mg m−3) and degree of fouling on the floor (77 vs. 37%) were significantly greater (P < 0.001) in the WSF compared with the WCF finishing rooms. Pigs in the WCF emitted 4.63 g NH3 pig−1 during the measurement period, whereas those in the WSF emitted 6.55 g NH3 pig−1. Our results indicate that, because pigs’ fouling behavior is established during the growing phase, the finishing phase should be performed in a similar facility designed to maintain the NH3 reduction provided by BAT systems. In this study, growers housed in a WSF facility exhibited the same defecating and urinating habits when moved to the WCF facility despite the availability of an outside alley. This management choice limited the capability to lower NH3 concentrations and emissions, negatively affecting animal performance.