The work had the objective to verify the response of a natural pasture, in the "Depressão Central of Rio Grande do Sul", Brazil, to pig slurry fertilization, in the doses of 0, 15, 30 and 45 m³/ha, equivalent to total application of 0, 76.5, 153.3, and 230.5 kg N/ha/cutting of N after each one of the four cuttings, between October/03 and February/04, totalizing 0, 60, 120, and 180 m³/ha of slurry. There was a linear increase of dry matter (DM) as function of pig slurry application. Compared to the control treatment, application of 45 m³/ha/cutting resulted in: a) 108% increase in the DM production (1.137 kg/ha/cutting; 4.549 kg/ha in total of the cuttings) and 42% in the pasture height (21 cm); b) 8% decrease in the ADF concentration (41.8%). The pig slurry application efficiency was, on average, 16.9 kg DM/m³/cutting. There was addition of soil chemical elements with fertilizer application, reaching a maximum of K = 200 mg/L; P= 52 mg/L; Ca = 1,8 cmol c/dm-3; Mg = 1,4 cmol c/dm. The 30 m³/ha/cutting can be a reference-value for the natural pasture in the spring-summer.
chemical composition; manure; nitrogen
