M.M. Namavari
M. Sayari
M. Kargar
M. Lotfi
M. Kamalzadeh

Neospora caninum (N. caninum) is an apicomplexan parasite and causes abortion and congenital neosporosis in cattle worldwide. In this study, we evaluate the virulence of a N. caninum isolate on mouse strain C۵۷BL/۶. Six groups of five mice C۵۷BL/۶ were intraperitoneally inoculated with ۱ × l۰۷, ۱.۵ × l۰۷, ۲ × l۰۷, ۳ × l۰۷ and ۴ × l۰۷ tachyzoites and a control inoculum of DMEM, respectively. Clinical signs and mortality rate were recorded and confirmed by histopathological findings and molecular method. The results of this study indicated that LD۵۰ was ۲.۵ × l۰۷ tachyzoites of N. caninum per C۵۷BL/۶ mouse. This can be used as a lethal challenge model in vaccine development studies.

Neospora caninum, C۵۷BL/۶ mouse model, LD۵۰