Development of freeze-dried bivalent fish vaccine product with skimmed milk as stabiliser

Bacterial vaccines have been tested for their effectiveness in protecting fish from potential virulent diseases. The current vaccine preparations are mostly in liquid form, which affects prices due to an increase in the cost of shipment, the stability of liquid products also has limitations in long-term storage. This study aims to develop a method of preparation of bivalent vaccine through freeze dry method with skimmed milk as a filler for optimization of the vaccine products. The preparation of bivalent vaccine by freeze dry method can reduce 96.67% of total weight compared to vaccines in liquid form. The quality test showed that bivalent vaccine products by freeze dry method with skimmed milk filler containing bacteria Aeromonas hydrophila and Streptococcus agalactiae are passed the sterility and viability test. The application of the vaccine can provide a positive response to increase the antibody titer and other hematological parameter responses and increase the survival rate of fish. The development of freeze-dried vaccine products can optimize fish vaccines as a recommended product in fish disease management.