龟源迟缓爱德华氏菌分离鉴定及灭活疫苗研制

Isolation and Identification of Turtle-Sourced Edwardsella laguna and Development of Inactivated Vaccine

【目的】利用从发病死亡的中华草龟(Chinemys reevesii)分离到的病原菌株制备灭活疫苗。【方法】对该菌进行培养特性、生理生化特征、16S rRNA同源性分析、药敏等试验。人工感染中华花龟(Ocadia sinensis),确定半数致死剂量(LD50)。经0.03%甲醛灭活后与铝胶3∶1制成灭活疫苗,对中华花龟进行腹腔注射免疫,测定血清抗体效价,以5LD50活菌浓度进行攻毒试验测定免疫保护率。【结果】分离鉴定该菌为迟缓爱德华氏菌。两次免疫14 d后抗体效价分别为1∶64和1∶256,在5LD50剂量攻毒后相对免疫保护率分别为60%和73%。【结论】本灭活疫苗二免的相对保护率达73%,有保护效果,可用于龟的迟缓爱德华氏菌病的预防。

【Objective】Inactivated vaccines were prepared using pathogenic strains isolated from Chinemys reevesii.【Method】Experiments were carried out on the culture characteristics,physiological and biochemical characteristics,16 S rRNA homology analysis and drug sensitivity of the bacteria.Artificially infected with Chinese Striped-neck Turtle(Ocadia sinensis)to determine the half lethal dose(LD50).After being inactivated with 0.03%formaldehyde,an inactivated vaccine was made with aluminum glue3:1.The Chinese Striped-neck Turtle was immunized intraperitoneally to determine the serum antibody titer.The challenge test was conducted with 5 LD50 live bacteria concentration to determine the immune protection rate.【Result】Isolated and identified the bacterium as Edwardsiella tarda.After 14 days of two immunizations,the antibody titers were 1∶64 and 1∶256.and the relative immune protection rates after5 LD50 dose challenge were 60%and 73%.【Conclusion】The relative protection rate of the second inactivated vaccine is 73%,which has a protective effect and can be used for the prevention of delayed Edwardsiosis of turtles.