Research on the Efficacy Test of Inactivated Vaccines against Sheep Septicemic Streptococcal Disease Using Mouse Immunochallenge
In order to solve the difficulties in animal screening,unstable animal quality,high economic costs and other problems in the efficacy test of inactivated vaccines against sheep septicemic streptococcal disease using target animal immunochallenge,a research on the alternative methods of immunochallenge in experimental animals was conducted.Based on target animal immunochallenge,the minimum protective dose and non-protective critical dose of the vaccine were determined,and a parallel research was conducted after confirming the variety of mice to select the optimal dose that could reflect the difference of the vaccine in the mouse model.The results showed that,for qualified vaccines,1/2 dilution was the minimum immune dose,and 1/4 was the critical dose in noncompliance of regulations;KM mice were the most suitable alternatives;2MLD mixture of bacterial solution was used as the optimal dose to challenge the immune group and control group,all the mice in the control group died,and at least 70%of those in the immune group were protected.An alternative method of efficacy test of inactivated vaccines against sheep septicemic streptococcal disease using mouse immunochallenge was established by the study,which will improve the stability and reliability of the efficacy test of such vaccines,and support the prevention and control of sheep septicemic streptococcal disease.