鸭疫里氏杆菌二价灭活疫苗制备及免疫效力研究

【目的】根据鸭疫里氏杆菌(Riemerella anatipestifer,RA)血清1型、2型贵州流行株制备二价灭活疫苗，为鸭疫里氏杆菌病的防控及疫苗研制提供研究资料。【方法】以血清1型RA(RA-G06株)、血清2型RA(RA-HS01株)地方流行株为菌种，通过涂板法测定菌株生长曲线，利用改良寇氏法计算菌株对鸭的半数致死量(median lethal dose, LD₅₀),将2株菌培养至终浓度为1×10¹⁰ CFU/mL后等比例混合，以卡波姆为佐剂制备二价灭活疫苗，经疫苗质量检验后进行雏鸭免疫试验；通过检测免疫鸭血清中特异性抗体水平和攻毒保护试验评价疫苗的保护率，对攻毒试验鸭心脏、肝脏、脾脏和脑组织进行组织病理学观察。【结果】RA-G06株和RA-HS01株均在培养12 h时到达峰值，活菌数分别为2.1×10¹¹和3.3×10¹¹ CFU/mL,LD₅₀分别为1.44×10¹⁰和2.63×10⁸ CFU/mL;制备的疫苗安全性良...

Preparation and Immune Efficacy of Riemerella anatipestifer Bivalent Inactivated Vaccine

【Objective】 The purpose of the test was to prepare bivalent inactivated vaccine according to Guizhou epidemic strains of Riemerella anatipestifer (RA) serotype 1 and 2, and provide research data for the prevention and control of RA infection and vaccine development.【Method】 The local epidemic strains of serotype 1 Riemerella anatipestifer (RA-G06) and serotype 2 RA (RA-HS01) were used as strains, and the growth curves of the strains were determined by the smear method and the modified Coulomb method was used to calculate the median lethal dose(LD₅₀) of the strains to ducks.After culturing to a final concentration of 1×10¹⁰ CFU/mL, the two strains were mixed in equal proportions, and then the bivalent inactivated vaccine was prepared with carbomer as an adjuvant, which was used to immunize ducks after the vaccine quality inspection.The protection rate of the vaccine was evaluated by detecting the level of specific antibodies in the sera of the immunized ducks and the challenge protection test, and the histopathology of the heart, liver, spleen and brain tissues of the ducks in the challenge test were observed.【Result】 RA-G06 strain and RA-HS01 strain both reached the peak value after 12 h of culture, the numbers of viable bacteria were 2.1×10¹¹ and 3.3×10¹¹ CFU/mL, LD₅₀ were 1.44×10¹⁰and 2.63×10⁸ CFU/mL, respectively.The prepared vaccine was safe and the humoral immunity could be induced in ducks.The results of RA-G06 strain challenge protection test showed that the protection rates of the self-developed vaccine and commercial vaccine were both 90%.The results of the challenge test of RA-HS01 showed that the protection rate of the self-developed vaccine was 90%, and the protection rate of the commercial vaccine was 80%.Histopathological results showed that after immunization, each vaccine group could provide better protection to duck heart, liver, spleen and brain tissues, and the self-developed vaccine group had obvious advantages.【Conclusion】 It showed that the carbomer adjuvant inactivated vaccine prepared by using RA serotype 1 and 2 strains circulating in Guizhou had obvious immune effect, and could play an important role in the prevention and control of RA infection in Guizhou.