Produtividade e valor nutricional do Capim-Elefante cv. BRS Capiaçu em diferentes idades de rebrota.

Abstract

The objective was to evaluate the productivity, chemical-bromatological composition, ruminal degradability of dry matter and digestibility of BRS capiaçu grass (Pennisetum purpureum Schum.) managed at five regrowth ages. A completely randomized design with the cultivar BRS capiaçu of elephant grass was submitted to five cut intervals (30, 60, 90, 120 and 150 days) in the summer with ten replications, making a total of 50 plots with a useful area of 4 x 2m. The height of the plant increased 79.31%, ranging from 1.03 meters with 30 days to 4.98 meters with 150 days of regrowth. There were daily increases in the production of dry matter in the order of 382 kg ha-1, with 49,859 kg ha-1 being produced at 150 days of regrowth. The dry matter content (P <0.01) and organic matter (P <0.01) increased linearly at different regrowth ages. The crude protein content (P <0.01), in vitro dry matter digestibility and in vitro digestibility of the neutral detergent fiber linearly reduced 0.037%, 0.196% and 0.256% per day, 7 respectively. Potential degradability of dry matter decreased from 68.9% at 30 days to 44.7% at 150 days of regrowth (0.194 percentage units per day). The rate of degradation of fraction B 'c' was not modified (P = 0.94), average of 1.46% hour-1. It is recommended the age to harvest between 90 and 120 days of regrowth.