Streptococcus canis
Streptococcus canis, strong beta-hemolytic colonies
on Sheep Blood Agar
Streptococcus canis  chains in BHI broth,
Gram stained
Cultural characteristics
Biochemical characters
Phylum Firmicutes, Class Bacilli, Order Lactobacillales, Family Streptococcaceae, Genus Streptococcus, Streptococcus canis  Devriese
et al. 1986. Lancefield group G.
Gram-positive cocci, nonmotile, grouped in pairs or chains.
Round, beta-hemolytic, nonpigmented colonies.Grows at 37 ºC. Aerobic, facultatively
anaerobic. Grows on complex media: Trypticase soy agar with 5% sheep blood,
Mueller-Hinton medium enriched with 5% sheep blood, Brain heart infusion medium.
A precipitate and clear supernatant are formed in broth cultures. CAMP-negative. No
growth in the presence of 6.5% NaCl or 40% bile. No growth at 45 ºC (admin note).
Isolated from animals (skin, upper respiratory tract & uro-genital tract, also from
bovine milk). Human isolates are rare.
In dogs can produce dermatitis, otitis, metritis, vaginitis or pharyngitis. In cats can
produce pharyngitis, sinusitis, septicemia or vaginitis. Isolated from liver, bone, heart
and lungs of a 4-days-old Terra Nova dog - admin note). In bovines can produce
mammitis. In humans may produce septicemia (rarely).
  1. Robert A. Whiley and Jeremy M. Hardie, 2009. Genus I. Streptococcus Rosenbach 1884, 22AL. In: (Eds.) P.D. Vos, G. Garrity, D.
    Jones, N.R. Krieg, W. Ludwig, F.A. Rainey, K.-H. Schleifer, W.B. Whitman. Bergey’s Manual of Systematic Bacteriology, Volume 3:
    The Firmicutes, Springer, 655-711.
  2. Holt J.G., Krieg N.R., Sneath P.H.A., Staley J.T. and Williams S.T., 1994. Bergey's Manual of Determinative Bacteriology, Ninth
    Edition, Williams & Wilkins, A Waverly Company, Baltimore, pp 527-558.
  3. Devriese L.A., Hommez J., Kilpper-Balz R. & Schleifer K.H.: Streptococcus canis sp. nov.: a species of group G streptococci from
    animals. Int. J. Syst. Bacteriol., 1986, 36, 422-425.
  4. P. A. Pesavento, M. J. Bannasch, R. Bachmann, B. A. Byrne and K. F. Hurley: Fatal Streptococcus canis Infections in Intensively
    Housed Shelter Cats. Vet Pathol 44:218-221 (2007).
  5. F Bert and N Lambert-Zechovsky: Septicemia caused by Streptococcus canis in a human. Journal of Clinical Microbiology, 03
    1997, 777-779, Vol 35, No. 3
  6. L. L. Tikofsky1 and R. N. Zadoks: Cross-Infection Between Cats and Cows: Origin and Control of Streptococcus canis Mastitis in a
    Dairy Herd. J. Dairy Sci. 88:2707-2713.
  7. BacDive - the Bacterial Diversity Metadatabase. Sohngen C., Bunk B., Podstawka A., Gleim D., Vetcininova A., Reimer L.C.,
    Overmann J. Nucleic Acids Res. 2015. doi: 10.1093/nar/gkv983. Epub 2015 Sep 30. PMID:  26424852.
Positive results for L-aminopeptidase, alkaline phosphatase, leucine arylamidase,
arginine hydrolysis, esculin hydrolysis (the DSMZ type strain is negative in API 20
Strep, and a wild strain isolated from dog was negative in API 20 Strep, but positive
after 48h incubation in API 20 A - admin note), beta-galactosidase, acid production
from: D-fructose, galactose, D-glucose, N-acetylglucosamine, lactose, maltose,
D-mannose, ribose, salicin, starch & sucrose.

Negative for hippurate hydrolysis (the DSMZ type strain is positive in API 20 Strep),
fibrinolysin, beta-glucuronidase, tyrosine, starch hydrolysis, Voges-Proskauer,
pyrrolidonyl arylamidase, acid production from: adonitol, amygdalin, L- or
D-arabinose, D-arabitol, dulcitol, erythritol, D- or L-fucose, beta-gentiobiose,
gluconate, 2-ketogluconate, inositol, inulin, D-lyxose, mannitol, methyl
alpha-D-mannoside, melezitose, melibiose, D-raffinose, rhamnose, sorbitol,
L-sorbose, D-tagatose, trehalose (few strains may be positive), D-turanose, xylitol, D-
or L-xylose & methyl beta-xyloside.

Alpha-galactosidase is variable. Some strain may give weak acid production from
(c) Costin Stoica
Culture media
Biochemical tests
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