- Volume 19 Issue 2
1. In the present experiment, necrotic myocarditis were produced only in suckling mice but also in weanlings or young adult mice by intraperitoneal inoculation with the Tyzzer's organism KK of cat origin, whereas the organism MSK from the mouse was not capable of producing such lesions. 2. Significant difference in pathogenicity for 1-to 6-week-old mice was demonstrable between the two organisms after intraperitoneal inoculation without cortisone.