Abstract: The growth curve of Aeromonas hydrophila L1 were studied in this paper. Orthogonal design was employed to test the best broth components for the strain growing, and the results showed that the best condition was peptone 10 g/L, yeast extract 15 g/L, sucrose 7 g/L, and K2HPO4 4.56 g/L, respectively. The antigenicity was strongest when the conditions of making vaccines was 0.2% formaldehyde at 28℃ for 36 h, and it is qualified by sterility test and safety inspection. The injected relative percent survival of vaccines reached 90% by animal protection test. These data provide the technical basis for vaccine mass production in the future.

Key words: grass carp; Aeromonas hydrophila, inactivated vaccine, optimization