(Object) This experiment was conducted to study the effect of different dietary types on nutrients digestibility,energy conversion and nitrogen metabolic efficiency in dairy cows.(Method) A single factor random block was used in this study.Sixteen Holstein cows were fed with four diets:A diet(forage was composed of corn silage,corn straw),B diet(forage was composed of corn silage,chinensis wildry), C diet(forage was composed of corn silage,corn stock,chinensis wildry),and D diet(forage was composed of corn ...