Abstract
Virulent strains of the coccidian parasiteToxoplasma gondii become attenuated so as to survive and complete their life cycle; however, it is not known whether the attenuation process is attributable to an innate cystogenic capacity of the parasite or to host-induced mechanisms. This report presents direct evidence of RH cystogenesis in non-immunised Fischer rats and subsequent attenuation of RH pathogenicity in non-immunised mice following a single passage through rats. Taken together, these preliminary observations tend to suggest that at least one mechanism ofT. gondii involves intermediate host attenuation.
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Lecomte, V., Chumpitazi, B.F.F., Pasquier, B. et al. Brain-tissue cysts in rats infected with the RH strain ofToxoplasma gondii . Parasitol Res 78, 267–269 (1992). https://doi.org/10.1007/BF00931740
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DOI: https://doi.org/10.1007/BF00931740