Chemical composition and the in vitro dry matter digestibility were evaluated in blades and stems at two stages of development and two insertion levels on tillers of signalgrass (Brachiaria decumbens), molassesgrass (Melinis minutiflora) and tifton 85 bermudagrass (Cynodon sp), in two seasons of the year (summer and autumn). Lower and upper leaf blades were sampled from the tillers, on the day of ligule exposure and 20 days thereafter, and stems segments located below of the upper leaf blade. The crude protein contents of leaf blades showed little differences among the species, but decreased with development from 18.8 to 14.6% and level of insertion from 18.9 to 14.5% from lower to upper position. Leaf blades of higher insertion level had a greater neutral detergent fiber and lignin concentrations. The IVDMD decreased as leaf aged and exhibited greater values when situated at lower insertion level and sampled in the autumn. The IVDMD of old leaf blades were higher to tifton 85 bermudagrass and lower to signalgrass. The average values of IVDMD of stems varied from 56.7 to 62.7%, according to stage of development and season of growth. The values were 56.9, 59.6 and 60.5% for the signalgrass, bermudagrass and molassesgrass, respectively.
Brachiaria decumbens; crude protein; Cynodon sp; Melinis minutiflora; neutral detergent fiber; nutritive value
