This work evaluated the bromatologic characteristics of corn silages, ensiled at different maturity stages. It was used a split plot in time in a randomized block design, with four replicates. Cultivars evaluated were Geneze 2004, Agroceres 1051, Pioneer 30S40 and Pioneer 30F90 ensiled in the following maturity stages: 0% milk line kernels (SLL), reduction of milk line in 1/3 of the kernel (1/3 LL), 1/2 of the kernel (1/2 LL), 2/3 of the kernel (2/3 LL), and formed black layer (CN). The percentage of DM of the silages ranged from 26.5% to 45.0%. The highest losses of effluents occurred in the silages from the cultivars AG1051 and P30S40, at the SLL stage, with no losses from the 1/2 LL stage. As the maturity stage advanced, increased values of pH occurred. Maturity stages influenced the percentage of CP of the silages which ranged from 10.7% to 8.1%. The greatest values of NDF (neutral detergent fiber) and ADF (acid detergent fiber) were found at the 2/3 LL and CN stages. The percentage of lignin was influenced by the cultivars, with the greatest values observed in the silages from the cultivar P30S40. The IVDDM (in vitro dry matter digestibility) was influenced by cultivar and maturity stage, varying from 51.1% to 69.8%, with the cultivar P30F90 presenting the greatest IVDDM. The 1/2 LL stage showed better IVDDM, reducing its value after this stage. The cultivars GNZ 2004, AG1051 and P30F90 are more indicated for ensiling and the best maturity stage for ensiling these two cultivars was when grains presented reduction of the milk line in half of the kernel (1/2 LL).
digestibility; dry matter; milk line
