Studies on the Bacteria Associated with European Foulbrood

Abstract

The studies give evidence that a pleomorphic organism may be the etiological factor. The bacteria in sick and dead brood consisted of coccoid cells, and of short, medium long, and long slender rods. Cultures from sick or dead larvae usually yielded either Bacillus alvei or Streptococcus apis in apparently pure culture, or both of these forms. Inoculation of healthy brood with bacteria from cultures isolated from infected larvae usually caused infection of only occasional larvae. In 1 exp. typical European foulbrood appeared to be produced by inoculation with a recently isolated culture of Strep. apis. B. alvei was found capable of morphological, cultural, and biological transformation. The characteristics of Strep. apis were also found to change in culture.