Abstract: The fermentation cultivation process of Avibacterium paragallinarum C-Apg-8(serovar A) had been improved in terms of inoculation method, culture time, the initial inoculation quantity of microorganism and so on.The results showed that the single-batch production capacity of Avibacterium paragallinarum fermentation could increase almost five times by changing the present two-step inoculation method(the primary seed→the secondary seed(7500 mL) →300 L) to the four-step inoculation method(4 mL→160 mL→1600 mL→30000 mL→300 L), and adjusting the inoculation proportion from 2.5% to 2.5%-10%.The improved cultivation way had been changed from spinner cultivation to fermenter cultivation without changing the volume of fermentation, and without adding the staff and the cost of raw material.

Key words: Avibacterium paragallinarum; fermentation cultivation; inoculation proportion