The effect of CCA and CCB addition on the gas production, VFA concentration for different diet mixtures in vitro was studied.

• 2）日粮类型也影响酶的作用效果，秸秆日粮中添加少量酶A显著提高VFA浓度、产气量，而精粗比为3：7日粮添加酶A仅提高产气量，对VFA浓度没有影响。