Digestibilidade de dietas a base de grão úmido de milho ou de sorgo ensilados

In vivo digestibility of diets with high moisture sorghum substituting corn was studied in 12 female bovines. Experimental design was completely randomized with three treatments, substituting high moisture corn by sorghum at 0, 50 and 100% levels. Diets contained high moisture corn or sorghum, soybean, urea, oat hay ( Avena sativa sp.), minerals and monensin. In situ degradability of corn and sorghum in cracking, grinding and silage processes was evaluated. There was no difference in apparent digestibility of crude protein, crude fiber, neutral detergent fiber and ethereal extract. Negative lineal effect was observed (P < 0,05) for apparent digestibility of starch with sorghum inclusion. Processing interacted with grain when effective degradation of dry matter was concerned (P < 0,01). Corn had the highest degradation in high moisture silage; the worst degradation occurred with cracked; an intermediate degradation occurred in grinding (P < 0,01). Degradation in silage was similar as that of cracked degradation in sorghum; it was worst in grinding (P < 0,01).