Evaluating of Wistar rat and BALB/c mouse as animal models for congenital, cerebral and ocular toxoplasmosis.

Abstract

This study was conducted to evaluate the potential of cyst production by Toxoplasma (T.) gondii, RH strain, in Wistar rat and BALB/c mouse and the purpose of this study was to introduce an animal model suitable for congenital, cerebral, and ocular toxoplasmosis. The mice and rats, considered as cerebral and ocular toxoplasmosis models, were intraperitoneally infected by different number of the parasite and their eyes and brain were evaluated for the presence of T. gondii cyst using the microscopic examination and the bioassay method. Moreover, the pregnant mice and rats, considered as congenital toxoplasmosis models, were intraperitoneally infected by different number of the parasite and their infants were examined by the method mentioned above. The best result for the cerebral toxoplasmosis model was observed in the rats infected with the 107 parasites, so that all infants (100%) were infected with the parasite when examined using the bioassay method. Furthermore, the best result was observed for the congenital cerebral toxoplasmosis model with 100% infection rate in the infants born to mothers infected with the 107 parasites. Overall, just few the ocular samples were positive using bioassay method. The best result in the current study was for the congenital cerebral toxoplasmosis model where the pregnant rats were infected with the 107 parasites and all infants were infected (100%). Therefore, these infants can be used as a congenital cerebral toxoplasmosis model when they are in the fetal stage, and can be used as a cerebral toxoplasmosis model one month after birth.