Erysipellothrix

Erysipelothrix rhusiopathiae on blood agar

Small, clear, circular colonies, which increase in size and tending towards a pale blue opacity with further incubation or age. It produces a narrow zone of alpha-haemolysis.

Erysipelothrix rhusiopathiae Gram stain

slender Gram positive non-sporulating rods occurring in short chains, in pairs, in a "V" configuration or even grouped randomly. This organism can appear Gram variable because of their tendency to decolourise rapidly.

Erysipelothrix rhusiopathiae Gram stain