Four hybrid forage sorghums with different tannin concentrations and moisture in the stem were ensiled in laboratory silos made of "PVC" tubes. The silos were opened 1 (P2), 7 (P3), 14 (P4), 28 (P5) e 56 (P6) days after ensiling, in order to evaluate fermentation patterns and other silage characteristics. Twenty-four treatments were used, with four repetitions each: four hybrids (T1=moist stem/low tannin, T2=not moist stem/low tannin, T3=not moist stem/high tannin, T4= moist stem/high tannin) and with six periods, since the forages before ensiling (P1) were also studied. Dry matter content (DM), cell wall content, tannin concentrations and in vitro dry matter digestibility (IVDMD) were determined. Data were evaluated by analysis of variance, with mean separation achieved using Tukey statistical test. Tannin concentration was reduced as silage fermentation developed, although the IVDMD was not increased.
Silage; sorghum; tannin; dry matter digestibility
