Carbon dioxide emission and water evaporation from deep litter systems are important parameters to consider when designing ventilation and heating in livestock buildings. The objective of these investigations was to determine the CO emission and water evaporation from deep litter with di!erent bedding materials and also the water evaporation from a manure alley (solid #oor). Five di!erent studies are presented, two with deep litter for young cattle and three with deep litter for growing/"nishing pigs. The bedding materials used were; long straw, chopped straw, chopped straw with reduced (25%) bedding amount, chopped straw with additives (four di!erent), wood shavings and a mixture with 60% peat and 40% chopped straw. The investigations with deep litter for young cattle were conducted during two 6-month periods and the investigations with deep litter for growing/"nishing pigs were conducted during three growing periods. Animal density in the pens varied between 27}101 and 22}90 kg m\ for cattle and pigs, respectively. Ventilated chambers (bottom area 0)25 m) placed on the top of the litter were used in four studies. In a "fth study, with deep litter for growing/"nishing pigs, the measurements were at building scale in the ventilated air when pigs were moved outside the research building.
The average CO emission rate measured by ventilated chambers varied between 24)0}87)9 and 23)0}82.2 g m\ h\ for cattle and pigs, respectively. The average water evaporation varied between 109)2}159)8 (cattle) and 70)3}190)6 g m\ h\ (pigs). From the manure alley (solid #oor), the average water evaporation rates in two studies (cattle) were 73)2 and 110)5 g m\ h. The water evaporation rate varied during the measuring periods, with the minimum occurring during winter months. For young cattle, long straw as bedding material had a signi"cantly higher CO emission rate compared with chopped straw. The mixture of peat and chopped straw had a signi"cantly lower CO emission rate and water evaporation rate than long straw and chopped straw. For growing/"nishing pigs, wood shavings as the bedding material had a signi"cantly lower CO emission rate and water evaporation rate compared with long or chopped straw. The four di!erent additives used had no signi"cant e!ect on the CO emission rate or the water evaporation rate. The CO emission rate measured at building scale was lower than from the measurements with ventilated chambers, between 12)9 and 21)9 g m\ h, and the water evaporation rate was between 135)6 and 210)5 g m\ h.