Forage sorghum silage with different tannin concentrations and moisure in the stem. III- Effect on nitrogenous compounds

L.C. Gonçalves N.M. Rodriguez F.S. Nogueira A.L.C.C. Borges C.P. Zago About the authors

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 others parameters. Twenty-four treatments were used, with four repetitions each: 4 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 were also studied. Dry matter content (DM), crude protein (CP), ammonia nitrogen (N-NH3) and tannin were determined. Data were evaluated by analysis of variance, with mean separation achieved using Tukey statistical test. All sorghums had N-NH3 production during the fermentation, which was lower in high tannin sorghums. The N-NH3 concentrations were lower than those in the literature. High tannin sorghums had higher dry matter contents.

Silage; sorghum; tannin; nitrogenous compound

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