Nutrient Characterization and Mineral Composition of Aruana in a Silvopastoral System with Nitrogen Fertilization

Abstract

The objective was to characterize the nutrient and mineral composition of M. maximus cv Aruana grazed by lambs in a silvopastoral system or full sun with added nitrogen. The treatments are: (1) Aruana grazed in full sun with nitrogen fertilization, (2) Aruana grazed in full sun without nitrogen fertilization, (3) Aruana grazed in a silvopastoral system with nitrogen fertilization and (4) Aruana grazed in a silvopastoral system without nitrogen fertilization. The nutrient dynamics, urinary excretion of N and the amount returned of the nutrient were determined from four sheep in a Latin square experimental design; the analysis of the mineral composition of the leaves and stalks of the grass was carried out by collecting samples from the plots used, totaling six in each treatment evaluated. The silvopastoral system provided high levels of P and K in forage plants. Urinary N excretion and urine mineral contents were influenced by the systems evaluated and the use of N fertilizer. N did not show differences for leaves and canes.