Evaluación de cinco residuos avícolas como fuentes de nitrógeno mineral disponible

The production of organic crops in Peru has significantly increased during the last decade, thus increasing the demand of organic sources with high availability of nitrogen, suitable to satisfy crop requirements. The mineralization of nitrogen in five residues of poultry production: layer manure (EP), reproducer manure (ER), broiler manure with chicken corpses (ERP), feather meal (HP) and floatation sludge (LF), was studied with the aim of evaluating their potential as rapid-release organic fertilizers. The residues were applied at a rate of 0.33% (p/p) in centrifuge tubes containing washed sand, and aerobically incubated at 25 ºC during 120 days. Mineral N fractions: nitrate (N-NO_3–) and ammonium (N-NH₄₊) were extracted from tubes and determined by colorimetric procedures at 0, 30, 60, 90 and 120 days of incubation. Nitrogen mineralization potential was calculated as the maximum amount of mineral N (N-NH₄ + + N-NO_3–) released during the incubation. Nitrogen mineralization rate was the highest at 30 days and continued until 120 days in feather meal, and until 90 days in the other sources. The organic residues showed N mineralization potential of 12 y 70%. Feather meal, layer manure and reproducer manure showed the highest N mineralization potential, and are promissory sources to be used as fertilizers in organic crops.