Produ？？o, composi？？o química e degradabilidade ruminal in situ de cultivares de cana-de-a？úcar

in this experiment the production, chemical composition, and in situ ruminal degradability of sugarcane varieties were evaluated. they were included in the research the varieties: rb867515, rb835486, rb758540, rb72454, rb928064, rb845210, rb739735, rb855536, rb855113, rb835054, rb858927, rb765418, sp81-3250, sp80-1816, sp80-3280, sp90-3414, sp91-1049, sp80-1842, sp79-2233, sp90-1638, sp83-2847, sp83-5073, sp86-155 and cb44-74. the agronomic characteristics and bromatological composition were evaluated following a randomized block design, with four replicates. the results obtained for the different variables were submitted to the tests of normality, multicollinearity, main components and the grouping scott knott test at the 5% significancy level. the most important variables for group discrimination were biomass production per ha (91,1%), neutral detergent fiber (4,54%), the non degradable fraction (i) (3,27%) and hemicelulose (1,08%). the grouping analysis permitted to discriminate three groups of varieties of sugarcane. the varieties rb855536, rb835486 and sp80-1842 were selected, based on the variables that had the higher discrimination power.