Responses of high-sugar ryegrass productive performance to stimulated grazing on the Loess Plateau

In the present study, the productive performance of 3 different introduced highsugar ryegrass cultivars were quantitatively analyzed in both simulated grazing conditions and making hay conditions in Loess Plateau. The results showed that the contents of crude proteins, crude fats and crude Ash of 3 cultivars in simulated grazing conditions were significantly higher than those in making hay conditions, while the content of crude fibers and water soluble carbohydrates in simulated grazing conditions were significantly lower than those in making hay areas (P0.05) which suggested that simulated grazing can significantly improved (P0.05) the contents of crude proteins, crude fats, crude Ash and water use efficiency. The simulated grazing significantly increased (P0.05) the yield of gross energy of ryegrass cultivar Star and Premium . The hay yield, water use efficiency and nutrient contents of cultivar Star in simulated grazing conditions were significantly higher (P0.01) than those of the other 2 highsugar cultivars Abermagic and Aberavon which had no significant difference between each other. In conclusion, simulated grazing improved the productive performance of highsugar ryegrass cultivars and the performance of Star had higher and stable performance．