The objective ofthis study was to evaluate the chemical composition and dry matter in vitrodigestibility of stem, leaf, straw, cob and kernel fractions of eleven corn(Zea mays) cultivars, harvested at two cutting heights. The experiment was designedas randomized blocks, with three replicates, in a 2 × 11 factorial arrangement(eleven cultivars and two cutting heights). The corn cultivars evaluated wereD 766, D 657, D 1000, P 3021, P 3041, C 805, C 333, AG 5011, FOR 01, CO 9621and BR 205, harvested at a low cutting height (5 cm above ground) and a highcutting height (5 cm below the first ear insertion). Cutting height influencedthe dry matter content of the stem fraction, which was lower (23.95%) in plantsharvested at the low, than in plants harvested at the high cutting height (26.28%).The kernel fraction had the highest dry matter in vitro digestibility(85.13%), while cultivars did not differ between each other. Cob and straw werethe fractions with the highest level of neutral detergent fiber (80.74 and 79.77%,respectively) and the lowest level of crude protein (3.84% and 3.69%, respectively).The leaf fraction had the highest crude protein content, both for plants oflow and high cuttings (15.55% and 16.20%, respectively). The increase in theplant cutting height enhanced the dry matter content and dry matter in vitrodigestibility of stem fraction, but did not affect the DM content of the leaffraction.
