The swine production industry in Brazil has been severely criticized due to pollution, mainly in water, that has been noticed in regions where swine production is concentrated. This fact puts in question the current production model. Deep bedding system for swine production appears as a promising alternative, because it reduces the risks of contamination by converting manure management from liquid to solid phase. Additionally, it makes possible the production of organic compost, which can generate extra income or can be applied in the same farm to implement an organic agricultural production. This study evaluated the increase of macronutrients, copper and zinc concentrations in wood shavings used as a substrate in four stalls during a period when 8 groups of 70 animals were raised. Each stall had animals installed during 35 days, according to their age of entrance (nursery = 21, S1 = 56, S2 = 91 and S3 = 126 days). Results have shown that average concentrations of nutrients in beds are in compliance with legislation for simple organic fertilizer. The concentration of zinc in the nursery bed was about 5 times higher than other stalls, which shows the influence of diet on the composition of the compost.
swine production; rejects; alternative management; organic compost
