Abstract
In the present experiment, various dilution of ectromelia virus were inoculated into the allantoic and amnionic cavities of embryonating eggs and the changes produced in biological and pathological findings were observed by serial passage in the former case and by the difference in viral concentration used in the latter case.
1. Biological findings of the embryonating eggs and mice as well as pathological findings of the liver of embryos were significantly strong even in the case of inoculation made into the allantoic cavity.
2. As biological findings of the inoculation made into the amnionic cavity of embryonating eggs and those of mice as well as histopathological findings of the embryonic liver, it was found, in contrast to the inoculation made into the allantoic cavity, that the onset rate of mice was much higher and the circulatory disturbance was much stronger though tissue disturbance was somewhat weaker.
3. Biological findings of the embryonating eggs and mice received the inoculation of ectromelia virus in a dilution of 10-5 and histopathological findings of the embryonic liver were weakened following the advance in the generation of passage.
4. Findings stated above were weakened by the inoculum of lower virus concentration.
5. Circulatory disturbance, however, was fairly strong through out all the experimental groups in spite of the advance in the generation of passage and lowering in the virus concentration.
6. Argentaffin fiber staining revealed the picture of fragmentation in the first experiment and frangmentation and proliferation in the second experiment.
