Nitrogen, phosphorus, potassium, copper and zinc in effluent from pigs fattened on slatted flooring or wood litter

This study compared nitrogen, phosphorus and potassium in effluent from pigs fattened using two different waste collection methods, slurry runoff and bedding manure. In weight the quantities of slurry produced were two to three times greater than the quantities of manure obtained. In volume, waste per pig doubled from manure to slurry (0.2 and 0.4 m3/pig respectively). The comparison of the two types of waste, slurry and manure, showed that spreading of one ton of manure supplied 60 to 70% more nitrogen than a cubic meter of slurry. The proportion of the nitrogen excreted by the pigs found in the waste was reduced by 40% on average when manure replaced slurry. The use of this type of litter can be considered as a method of processing that will reduce nitrogen directly under the animals. In five months sheltered storage without turning, the manure lost only 20% of its initial weight, i.e., half the value that would have been expected after composting.