Growth of P. intermedia strains 17 and 17-2 in enriched-trypticase soy broth and scanning electron micrographs showing morphological changes associated with growth. Strains 17 and 17-2 entered into the exponential phase at a different time point. Strain 17-2 shows a faster growth rate (A). Meshwork-like structures around strain 17 cells were observed at 12 h and became denser with time. Arrowheads indicate cells with meshwork-like structures (B). No such morphological changes were observed in strain 17-2 (C).