164 Chemical composition and in vitro digestion of reconstituted and ensiled sorghum grains for pig feeding.

摘要

It is expected that the digestive use of cereals increase when subjected to anaerobic fermentation processes, especially in grains such as sorghum, where the utilization of nutrients and energy for monogastrics is limited. The objective of this study was to compare the chemical composition and in vitro digestibility of sorghum grains harvested at high moisture or subjected to water reconstitution and ensiled to assess its use in swine feeding. A sorghum crop paddock was divided into 9 plots and assigned to three treatments in a complete randomized block design: grain harvested at 40% moisture (high moisture sorghum; HMS), grain harvested dry and reconstituted by water addition up to 40% moisture (reconstituted sorghum; RS) and grain harvested dry (dry sorghum; DS). HMS and RS grains were grounded and anaerobically stored inside silo drums for 180 d. The pH in the silos was measured immediately after opening the drums. Silages were analyzed for dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fibre (NDF), starch, and a two-step procedure using pepsin and pancreatin was performed to determine DM, OM and starch in vitro digestibility (IVDig). Data was analyzed using a mixed model considering the fixed effect of treatments and means were separated by Tukey test. Except for the lower DM content of ensiled grains, the chemical composition of the grains was similar for the different treatments (Table 1). The ensiling process (HMS and RCS) caused an increase of 34, 36 and 46% in the in vitro digestibilities of DM, OM and starch, respectively (P=0.002; P=0.004; P=0.006). Ensiling of early harvested grains and water reconstitution of dry grains can be an alternative to improve the digestibility and nutritive value of sorghum grains for pigs.