In this study,the content of polyphenol and nutrient content and its the dynamic law, gas production in vitro, dry matter disappearance and ruminal ferment parameters of the main desert shrubs and alfalfa in different growthing stages were compared. The relationship of nutritional components, gas production in vitro, dry matter disappearance and rumen fermentation parameters compared with the polyphenol of shrubs were researched respectively. It was provided the basic data for developing and utiliza...