The current experiment was carried out to evaluate the nutritive value (dry matter and crude protein) of six sorghum silage genotypes, with or without tannin on grain, harvested in the hard dough stage, by in situ degradability technique. Six sorghum silage genotypes (BR 303, BR 304, BR 601, and AG 2006 without tannin on grain, and BR 700 and BR 701 with tannin on grain) were used. Four crossbred steers, canulated in the rumen, were used for incubation tests. Incubation times were: 6, 12, 24, 48, 72, and 96 hours. The time zero (t0) were used to evaluate the soluble fraction. The BR 304 sorghum silage was better than others to mean disappearance of the dry matter and crude protein, at 96 hours of incubation. The tannin on grain, of the BR 700 and BR 701 sorghum silages (harvested at hard dough stage), didn't influence degradability parameters of the neutral detergent fiber, and acid detergent fiber.
Sorghum silage; In situ degradability; Tannin; Dry matter; Crude protein
