[Streptococcus pneumoniae multiplication in the allantoic cavity of developing chick embryos]

The possibility of the active multiplication of S. pneumoniae (serotypes 1, 3, 6 and 19) in the allantoic cavity of chick embryos has been demonstrated. This multiplication is accompanied by the development of characteristic changes whose intensity and time of manifestation have been found to depend on the infective dose and the age of the embryo. The accumulation of S. pneumoniae in the allantoic cavity of chick embryos in the absence of visible changes in the biological properties of the infective agent after 5 successive subcultures makes it possible to recommend chick embryos as a model for the study of experimental pneumococcal infection.