Gaseous emissions from weaned pigs raised on different floor systems Jean-Franc ¸ois Cabaraux a, *, Franc ¸ois-Xavier Philippe a , Martine Laitat b , Bernard Canart a , Marc Vandenheede a , Baudouin Nicks a a Veterinary Ecology and Ethology Unit, Department of Animal Production, Ba ˆt. B43, Faculty of Veterinary Medicine, University of Lie `ge, Boulevard de Colonster 20, 4000 Lie `ge, Belgium b Department of Production Animals Clinic, Baˆt. B42, Faculty of Veterinary Medicine, University of Lie `ge, Boulevard de Colonster 20, 4000 Lie `ge, Belgium 1. Introduction Agriculture contributes importantly to pollutant gaseous emissions such as ammonia (NH 3 ), carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) (Monteny et al., 2006; Aneja et al., 2007). These gases have a number of environmental bad effects. NH 3 contributes to the acidification and eutrophication of soils and waters (Brink et al., 2001) and to indirect emissions of N 2 O (Intergovernmental Panel on Climate Change, 2006a). Further- more, NH 3 is well known as a toxic gas, irritating the respiratory tract at concentrations exceeding 15 ppm (Urbain, 1997). In Europe, approximately 80% of NH 3 production originated from animal production facilities (Brink et al., 2001). According to van der Peet-Schwering et al. (1999), approximately 50% of the ammonia emissions from pig production are from pig housing and slurry storage. The other 50% is emitted during surface application of the slurry. CO 2 , CH 4 and N 2 O are the most important greenhouse gases (GHG) associated with livestock production. These gases take part to the global problem of climate change. However, agriculture is also a CO 2 -consumer through plant photosynthesis and the contribution of CO 2 to the greenhouse effect is less important than that of CH 4 and N 2 O, whose warming potentials over a 100- year period are, respectively, 21 and 310 times that of CO 2 (Intergovernmental Panel on Climate Change, 2007). N 2 O also contributes to the destruction of the ozone shield. Approximately Agriculture, Ecosystems and Environment 130 (2009) 86–92 ARTICLE INFO Article history: Received 28 March 2008 Received in revised form 24 November 2008 Accepted 26 November 2008 Available online 20 January 2009 Keywords: Weaned pigs Deep litter Slatted floor Ammonia Greenhouse gases Water vapour ABSTRACT Gaseous emissions from agriculture contribute to a number of environmental effects. Carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) are greenhouse gases taking part to the global problem of climate change. Ammonia (NH 3 ) emissions are responsible of soil acidification and eutrophication and contribute also to indirect emissions of N 2 O. This work evaluated the influence of the type of floor on the emissions of these gases in the raising of weaned pigs. Two trials were carried out. In the first trial, the animals were kept either on fully slatted floor or on straw-based deep litter and, in the second one, either on fully slatted floor or on sawdust-based deep litter. For each trial and on each type of floor, 2 successive batches of weaned pigs were raised without changing the litter or emptying the slurry pit between the 2 batches. The rooms were automatically ventilated to maintain a constant ambient temperature. The performance of the animals was not significantly different according to the floor type. In trial 1, the nitrogen contents of the straw deep litter (including the substrate) and slurry were respectively 276 and 389 g pig 1 . In trial 2, the sawdust deep litter and slurry nitrogen contents were respectively 122 and 318 g pig 1 . Raising pigs on straw deep litter produced proportionately around 100% more NH 3 than raising pigs on slatted floor (0.61 g NH 3 -N d 1 pig 1 vs. 0.31 g NH 3 -N d 1 pig 1 ; P < 0.05). Differences in CO 2 ,H 2 O and CH 4 emissions were not significant between systems. Raising pigs on sawdust deep litter produced also proportionately more NH 3 (+52%; 0.55 g NH 3 -N d 1 pig 1 vs. 0.36 g NH 3 -N d 1 pig 1 ; P < 0.01) but also more CO 2 (+25%; 427 g d 1 pig 1 vs. 341 g d 1 pig 1 ; P < 0.001) and H 2 O (+65%; 981 g d 1 pig 1 vs. 593 g d 1 pig 1 ; P < 0.001) and less CH 4 (40%; 0.52 g d 1 pig 1 vs. 0.86 g d 1 pig 1 ; P < 0.001) than raising pigs on slatted floor. Practically no N 2 O emission was observed from rooms with slatted floor while the N 2 O emissions were 0.03 and 0.32 g N 2 O-N d 1 pig 1 for the straw and sawdust deep litter respectively. The warming potential of the greenhouse gases (N 2 O + CH 4 ), were about 22, 34 and 168 g CO 2 equivalents per day and per pig on fully slatted floor, straw or sawdust deep litter respectively. In conclusion, pollutant gas emissions from rearing of weaned pig seem lower with fully slatted plastic floor system than with deep litter systems. ß 2008 Elsevier B.V. All rights reserved. * Corresponding author. Tel.: +32 4 366 59 03; fax: +32 4 366 41 22. E-mail address: jfcabaraux@ulg.ac.be (J.-F. Cabaraux). Contents lists available at ScienceDirect Agriculture, Ecosystems and Environment journal homepage: www.elsevier.com/locate/agee 0167-8809/$ – see front matter ß 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.agee.2008.11.016