| Abstract: | Two parts were involved in this experiment. In experiment 1, 32 Chinese Holstein cows with relatively similar body condition, lactation number and days in milk were selected. The cows were assigned in a randomized complete block design trial to determine the effect of supplemental Bacillus cultures to diet on production performance in dairy cattle. Four treatments, i.e., Bacillus licheniformis (strain number 1.813) group, Bacillus subtilis (strain number 1.1086) group, Bacillus cereus var. mycoides (strain number 1.260) group and control group. Each treatment had eight replicates, each replicate had one cow, 50 g per head per day. Results showed that Bacillus licheniformis group increased the milk yield (P<0.05). The other two groups didn't have significant effect on milk yield than the control group (P>0.05). In experiment 2, 3 Chinese Holstein cows with permanent fistulas were used. 3×3 Latin squares were assigned to three diets: Bacillus lincheniformis culture, Bacillus subtilis culture and control. Bacillus licheniformis culture increased total rumen microorganism (P<0.05), decreased the ammonia N concentration at 2, 4 h (P<0.05). Bacillus licheniformis culture increased the total volatile fatty (P>0.05), increased the rate of acetic acid to propionic acid (P>0.05). Bacillus licheniformis culture decreased the methane production (P>0.05). |
