Development of A Production Procedure for Bulk of Inactivated Mandarinfish Pathogenic Aeromonas hydrophila Vaccine

Objective To develop a production procedure for the bulk of inactivated mandarinfish pathogenic Aeromonas hydrophila vaccine.Methods Aeromonas hydrophila GYK1 strain was cultured in shake-flask and 5 L fermenter for various hours and determined for A650.The bacterial culture was inactivated with formaldehyde solution at various concentrations for various hours,and the inactivation effect was evaluated.The strain was cultured in shake-flask,seed tank and fermenter in turn,then inactivated with formaldehyde to prepare the bulk of inactivated vaccine which was tested for safety and potency.Results The growth of strain reached a stable stage 18 h and a peak value 24 h after culture in shake-flask.However,in 5 L fermenter,the growth of strain reached a stable stage 8 h and a peak value about 10 h after culture.The bacterial liquid was completely inactivated with 0.30% formaldehyde at 37℃ for 24 h,and the residual formaldehyde was low.The prepared bulk of inactivated vaccine showed high safety and was qualified in potency test.Conclusion A production procedure for the bulk of inactivated mandarinfish pathogenic Aeromonas hydrophila vaccine was preliminarily developed.