The Reaction of the Chick Embryo to Virulent and Nonvirulent Strains of Bact. Tularense

Abstract

Strains of Bact. tularense virulent for other animals when inoculated on 14-day-old chick embryos produced rather constant reaction and death occurred within 72 to 120 hrs. Nonvirulent strains produced no visible change or only occasional focal papules on the chorioallantoic membrane. With adequate controls. standardized inocula, recognition of accidental deaths, and sufficient numbers, the 14-day-old chick embryo would appear to be suitable for virulence and therapeutic tests when compared with the results obtained with white mice.