Special Operations Forces Medical Handbook

8-49

What Not To Do: Do not dig too deeply in obtaining superficial cells for examination. Do not overheat
slide.

Lab Procedure: Culture Interpretation

18D Skills and Training Manual

When: To microscopically differentiate between species of microorganisms.

What You Need: Glass slides, coverslips, a microscope, a lab request form and a logbook.

What To Do:

1. Identify colonies by shape
   a. Circular
   b. Undulate
   c. Lobate
   d. Radiated lobated
   e. Crenated
   f. Dentated
   g. Concentric
   h. Regular myceloid
   i. Irregular (curled undulated edges)
   j. Irregular (filamentous)
   k. Irregular (rhizoid)


2. Identify colonies by size
   a. Dwarf = smaller than 0.5 mm
   b. Pinpoint = 0.5 mm
   c. Small = 1 mm
   d. Medium = 2 mm
   e. Large = 3 mm
   f. Spreading = 6 mm


3. Identify colonies by texture
   a. Smooth
   b. Rough
   c. Mucoid


4. Identify colonies by color. Colonies vary in color from clear white to violet.


5. Identify colonies by elevation
   a. Flat
   b. Raised
   c. Convex
   d. Umbilicated
   e. Umbonate
   f. Papillary
   g. Convex Rugose


6. Identify colonies by biochemical reaction
   a. Hemolytic
   b. Non-Hemolytic


7. Identify specific colony types based on their morphology
   a. Staph. aureus colonies are usually opaque, circular, smooth, raised and 1-3 mm in diameter. They
   may or may not be pigmented. They vary in color from white to golden. On blood agar, Beta hemolysis
   (clear halos) is seen around growing colonies (see Color Plates Picture 24).