Influence of liquid nitrogen cryopreservation to survive capability of Babesia microti standard strain / 中国人兽共患病学报

ABSTRACT

We discussed the influence of liquid nitrogen cryopreservation to survive capability of Babesia microti standard strain.The whole blood of mice infected with Babesia microti was put in liquid nitrogen to cryopreservation for 1 month,3 months,6 months,9 months,the whole blood was get out respectively and recovery at room temperature,and infected 3 mice respectively,100 μL/ mouse (the first generation after redissolution,the experiment group).In the same time,3 mice were also infected with Babesia microti as the animal conservation control group.When the infection rate was at a high level,the whole blood of the experiment group mice were injected into 3 normal BALB/c mice (the second generation after redissolution),to observe the changes of the Babesia microti form and proliferation situation,and also to observe the infection rate of the first and the second generation after redissolution in different conserving time.Compared with Babesia microti of animal subcultivation,the form of Babesia microti of liquid nitrogen cryopreservation changed a little.Small trophozoites,annular trophozoites,schizont and immature and mature merozoite and other form can also be seen.Compared with Babesia microti of animal subcultivation,the first time to see the worms and the time attaining to the high infection level were 1 to 2 days later,but for the second generation after redissolution,it is the same.There was no significant difference in different conserving time of 1,3,6,9 months.The influence of liquid nitrogen cryopreservation to survive capability and worm form of Babesia microti is a little,so liquid nitrogen cryopreservation can be a better way to conserving Babesia microti.