This work had the objective of evaluating the effects of different per
centages of corn (Zea mays L.) cob on the quality of the silage of hig
h-moisture corn grains. The following treatments were studied: percent
ages of corn cob in the silage (0, 5, 10, 15 and 20%); period of sampl
ing after opening the silos (zero, two, four and six days). The factor
ial arrangement 5 x 4 was studied according to a completely randomized
block design with three replications. The variables studied were not
affected by the sampling period. The buffering capacity and the pH wer
e not affected by the cob, while the percent soluble carbohydrates and
amoniacal nitrogen increasing until 1.2 and 1.89 unit percent, respec
tively. Increasing the amount of corn cobs reduced the contents of DM
(from 63.9% to 58.6%), CP (from 10.0% to 7.3%), EE (from 4.87% to 3.92
%) and the values of DMIVD (from 90.5% to 79.1%) in the silages and in
creasing the contents of acid detergente fiber (ADF) (from 3.3% to 12.
9%) and neutral detergente fiber (NDF) (from 15.16% to 26.1%). The val
ues of brute energy (BE) were not affected (P>0.01) by the cob corn in
the silage.