Bilan environnemental de l'hébergement de porcelets sevrés sur litière accumulée de sciure

Six batches of weaner pigs (N=440) were reared successively on a deep litter with sawdust without cleaning between the batches. The average liveweight of the pigs at the beginning and at the end of the post-weaning period was 8.42.4 and 26.04.6 kg. The average daily gain was 42298 g. Each piglet needed 12 kg of sawdust and produced 15 kg of manure. The average temperature of the litter at 20 cm depth was 33.8C. At the end of the experimental period, the dry matter (DM) content of the litter was 49% and the N content 19 g/kg DM. The C/N ratio decreased progressively from 82 to 25. The water evaporation rate was 92% and the N gas-emission rate 75%. The amount of N in the compost was 139 g/piglet. The average NH3 concentration in the experimental rooms was 8.75.2 ppm and the dust concentration 270136 particles/ml. 90% of particles were in the size range of 0.3-0.5 m. To decrease the dust concentration water was regularly added to the litter at a rate of 0.94 l/kg sawdust.