Preparation Of Inactivated Vaccine With Haemophilus Parasuis

Haemophilus parasuis is a member of the family Pasteurellaceae and commensal organism of the upper respiratory tract of conventional pigs.Under appropriate conditions it can invade and cause severe systemic disease,characterized by fibrinous polyserositis,arthritis and meningitis.Haemophilus parasuis is a non-motile, nicotinamide adenine dinucleotide(NAD)-dependent,Gram-negative bacterium. Currently,H.parasuis infections is one of the important diseases,which produces significant mortality and morbidity in piglets,causing an important economic losses in pig industry in China.However,there isn't an effective way to prevent and control the outbreaks of this disease.The present study,biological characterization and the virulence of Haemophilus parasuis isolate ZJ0402 was identified.And an indirect ELISA for detection of antibodies against Haemophilus parasuis was developed.Finally,the safety and efficiency of a inactivated vaccine of Haemophilus parasuis against Glasser's disease were evaluated.(1) Study on the biological characterication of Haemophilus parasuis isolate ZJ0402: In order to prepare inactivated Haemophilus parasuis vaccine,the growth properties, biochemical characters, the sensitiveness to some disinfectant, storing condition and the optional inactivating method of Haemophilus parasuis isolate ZJ0402 were studied.The results showed as following:Adding 0.002% NAD to growth medium could provide the greatest density after inoculation for 10h at 37℃ .After 50 passage of Haemophilus parasuis in culture medium the biochemical characters of the isolate did not change greatly.The Haemophilus parasuis was sensitive to the benzalkonium bromide solution by 1:10000 dilution and peroxyacetic acid by 1:3000 dilution.Meanwhile, the isolate could be inactivated by 0.2% Formalin at 37℃ for 14h.In addition,the isolate could keep its activity at -20℃ for 2 months or -50℃ for 4 months in 20% glycerol solution.But freeze drying could make the isolate...