Abstract: The experiment was aimed to research on fermentation level of Bacillus coagulans strain applied for animals by adopting segmented fed-batch fermentation technology.The fed-batch in exponential and stationary phases were respectively increase the number of bacterium and promoted spore formation. The results showed in exponential phase that the quantity of starch additives was 10% of the total,the quantity of soya bean flour and fish meal additives was 5% of the total,the best fed-batch mode was fed twice equally (interval time for 10 to 12 h),on this conditions the living bacteria amount could reach 8.30×10⁹ CFU/mL from 6.80×10⁹ CFU/mL. The results showed in stationary phase that the best fed-batch concentration was calcium carbonate 0.10 g/L,sodium dihydrogen phosphate 0.156 g/L and methionine 0.30 g/L,the best fed-batch mode was one-off feeding,on this conditions the ratio of spore-forming could reach 85.63% from 75.78%. Therefore, the research through the experiment on Bacillus coagulans suggested that both the living bacteria and the ratio of spore-forming of fermentation broth were further increased by adopting segmented fed-batch fermentation technology.

Key words: Bacillus coagulans; the ratio of spore-forming; fermentation optimization; segmented fed-batch fermentation technology