The relationship between seasonal forage digestibility and forage nutritive value in different grazing pastures
The digestibility of dry matter in forages collected from Maqu alpine meadow,swampy meadow, Pingshan lake desert steppe of Zhangye in Gansu and temperate steppe in Xinjiang was analyzed using the nylon bag method in 5 rumen-fistulated sheep.The digestibility of forage dry matter in alpine meadow and swampy meadow in high altitude areas was significantly higher than that of herbage from desert steppe of low altitude areas.In addition,the digestibility of forage dry matter in alpine meadow and swampy meadow tended to rise in spring to a peak in June and then decline in late season,while the opposite trend was observed in Pingshanlake desert steppe of Zhangye.In contrast,the digestibility of forage dry matter in Xinjiang temperate steppe exhibited a declining trend as herbage progressed through flowering,seed set,and hay stages of growth.As expected,forage dry matter digestibility was significantly positively correlated (P <0.01 )with forage crude protein (CP)content,and significantly negatively correlated (P <0.01)with ADF and NDF in alpine meadow. That is,forage growth stage was negatively correlated with CP content and DMD,but was highly positively correlated with DM,ADF,and NDF (P <0.01 ).The study indicated that the forage from alpine meadow in June,July and August had very high nutritional content,and is ideal to meet the energy needs of maintenance and growth,for grazing livestock.
国家科技期刊平台
NSTL
万方数据
维普
