Aguiar et al., 2006. Rev. Bras. Zootec., 35 (6): 2226-2233
The research was carried out to evaluate yield, chemical composition and losses of chopped tropical grass hays with the following forages: pearl millet (Pennisetum americanum), sudangrass (Sorghum sudanense), elephantgrass (Pennisetum purpureum) and two cultivars of forage sorghum (SF-25 and IPA-467-4-2) (Sorghum bicolor). The materials were harvested at 30% flowering, except for elephantgrass (60 days). The experiment was conducted according to a complete randomized block design, with five treatments and four replications. There were significant differences among hay productions with sorghum cultivars IPA-467-4-2 and SF-25 reaching the highest yields (10.85 and 10.65 t/ha/cut). Production of elephantgrass, sudangrass and pearl millet hays were respectively of 6.94, 6.69, and 4.93 t/ha/cut. Percentage of hay losses were not different among all treatments and varied from 17.33 to 20.17%. Pearl millet and sudangrass hays had the highest CP concentrations (10.56 and 8.80%), which were superior to elephantgrass (6.76%) and sorghum cultivars (5.62 and 5.50%). Most of the NDF values were superior to 70.0%. Sorghum cultivars exhibited the lowest NDIN concentration (0.42 and 0.40% of DM). The ADIN concentration ranged from 0.06 to 0.30% of DM. The highest lignin (%DM) concentration was observed for pearl millet (6.52%) and sorghum IPA-467-4-2 (6.17%) hays. Estimated TDN of the hays showed significant differences and sudangrass reached the highest value (53.35%). Production of chopped tropical grass hays showed high yields and chemical composition according to the minimum standards for ruminant nutrition.