Colony Morphology

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Colony Morphology

  • The growth observed on the anaerobic blood agar plate after 48 hours incubation (see upper image), revealed a spreading colony.
  • The spreading nature of the colony is better observed in the lower image.
  • No growth was observed on subcultures incubated aerobically indicating that this isolate is truly an anaerobe (although aerotolerance studies would be needed for confirmation).
  • The spreading nature of the colony and the lack of hemolysis are highly suggestive of Clostridium septicum. However, biochemical confirmation is necessary.