Emissions of ammonia, nitrous oxide, methane, carbon dioxide and water vapor in the raising of weaned pigs on straw-based and sawdust-based deep litters

Abstract

Five successive batches of 40 weaned pigs were raised on deep litter of sawdust or straw without changing the litter in between batches. The quantity of litter dry matter utilized in the two cases was 5 kg per pig. The concentrations of gases were measured 8 times, at about one-month intervals, for 6 consecutive days and the ventilation flow was recorded continuously. Pig raising on sawdust-based litter differed from that with straw by an emission of 2.6 times less ammonia (0.46 vs. 1.21 g per pig per day), 2.1 times less methane (0.77 vs. 1.58 g per pig per day), 3.9 times more N 2 O (1.39 vs. 0.36 g per pig per day), 4% more CO 2 (481 vs. 463 g per pig per day) and 21% more H 2 O (1126 vs. 933 g per pig per day). All differences were significant. About 58% of the nitrogen excreted by the pigs was recovered in the gas form and for the two litters, about 79% in the form of N 2 .