VetBact

Phylum	Class	Order	Family	Genus	Species/Subspecies

Species/Subspecies:

Rhodococcus equi

Etymology:

Genus name: red coccus (grain or berry)
Species epithet: from horse

Significance:

[Very important]

Old Species Name(s):

Corynebacterium equi

Taxonomy:

Phylum	Class	Order	Family	Genus
Actinobacteria	Actinobacteria	Actinomycetales	Nocardiaceae	Rhodococcus

Type Strain:

ATCC 25729 och 6939 = CCUG 892 = NCTC 1621

Macromorphology (smell):

Large glistening colonies, which often flow together on the agar plate due to strong mucus production (capsule). On purple lactose agar and Sabouraud agar, the colonies turn salmon-pink due to production of a γ-carotene like pigment. Typical odor (underground cellars, old stumps or rotten pear).

Micromorphology:

Can undergo different morphological stages during culture from rods (exponential phase) to cocci (stationary phase).

G+

Aerobic

+/-

Esculinase -, hippuricase (-), tryptophanase -, urease (+)

Biochemical Tests:

Hydrogensulphide (H₂S) v.

Fermentation of carbohydrates:

R. equi does not ferment carbohydrates.

Microbiological tests:

R. equi does not produce hemolysis on blood agar, but it gives synergistic hemolysis with Staphylococcus aureus subsp. aureus or Corynebacterium pseudotuberculosis. Synergistic hemolysis can be demonstrated by the so-called CAMP-test.

Spec. Char.:

Hosts:

Horse (pig, cattle, cat)

Reservoir:

Soil

Disease (Swedish):

Luftvägsinfektioner (bronkopneumoni) och lungabscesser hos föl mm.

Disease (English):

Pyogranulomatous bronchopneumonia (granulomatous pneumonia) and cranioventral abscesses in foals etc.

Clinical Picture:

Genome Sequence: