Biodegradable Microspheres as a Oral Vaccine Delivery System against Aeromonas hydrophila of Soft-shelled Turtles:The Optimization of the Inactivating Method

The inactivation of the virulent strain Z-1 of Aeromonas sobria with the different concentration of formalin(0.05%,0.1%,0.2% and 0.4%) at 4℃,28℃ and 37℃,were studied by testing the bacteria survival,hemolytic activity of extracellular products and antigenicities of bacterin at regular intervals.The concentration of formalin,temperature and inactivating time revealed the effects on inactivation of Aeromonas sobria.The time for inactivate bacteria and ECP of strain Z-1 was inversely propotional to studied temperature and concentration of formalin and differed greatly at the same concentration of formalin and temperature.The antigenicity of bacterin inactivated with 0.2% formalin at 28℃ for 48 hours could be the best among the various inactivating methods.