Consumo e digestibilidade aparente dos nutrientes de dietas contendo sorgo em grão seco ou reidratado e ensilado para novilhos nelore confinados

Abstract

We tested two processing techniques for sorghum grain, dry ground (SS) and rehydrated and ensiled (SR). We used 16 Nelore steers with average weight of 397.81 kg at the beginning of the experiment. The diet consisted of grain sorghum, sugar cane silage, whole cottonseed and protein concentrate based on soybean meal, urea and minerals. The intake and apparent digestibility of dry matter (DM), organic matter (OM) and nutrients, crude protein (CP), neutral detergent fiber corrected for cincas and protein (NDF), acid detergent fiber (ADF), (EE), non-fiber carbohydrates (NFC) and starch have been tested. The fecal pH was also evaluated. The addition of water to dry sorghum increased moisture of the material from 13.6 to 39.6% and silage produced had pH of 4.03. There was no effect (P> 0.05) of the processing thecnique on intake and digestibility of DM, OM, CP, NFC and starch. The starch content in faeces was 19.33% for the SS treatment and 18.44% for SR. As the SR has been ground into a sieve of 8 mm, the whole grain was lost in the faeces of this treatment, the SS is milled through sieve 2.5 mm. The intake of NDF in% PV and UTM and ADF intake were lower in rehydrated sorghum diet, digestibility of NDF was similar among treatments, the digestibility of ADF was lower in sorghum rehydrated treatment. The total digestible nutrients (TDN) obtained for the diets were similar, 66.51 and 67.63% for diets SS and SR, respectively. The SR treatment faeces pH (SR 6.74) was higher than the SS treatment's (6.23), suggesting that a lower part of the starch was fermented in the large intestine.