Streptococcus canis sp. nov.: A Species of Group G Streptococci from Animals

Abstract

f3-Hemolytic group G streptococci from cows with mastitis and from dogs with different pathological conditions were characterized and named Streptococcus canis sp. nov. These animal group G strains were differentiated from Streptococcus dysgalactiae (group G strains of human origin, as well as group L strains and certain animal and human group C strains) by simple physiological and biochemical tests. Deoxyribonucleic acid-deoxyribonucleic acid hybridization showed that the S . canis strains differed from S . dysgalactiae, Streptococcus pyogenes, Streptococcus equi, and Streptococcus salivarius. These organisms contain a rare cell wall peptidoglycan type, namely, Lys-Thr-Gly. The specific epithet of S . canis, which has been in use for many years in veterinary textbooks to designate group G strains isolated from dogs, was chosen for this proposed new species because it comprises animal but not human group G streptococci. The type strain is strain STR-T1 (= DSM 20715).Streptococci belonging to Lancefield group G (15) form a heterogeneous collection of organisms. At least the following three distinct groups can be found: (i) the large-colony form of P-hemolytic group G streptococci isolated from humans; (ii) large-colony P-hemolytic strains from animals which were first shown to differ from human group G strains in their fibrinolytic activity (3) and later also in several other characteristics (6); and (iii) the "minute P-hemolytic colony" group G strains from humans.Animal group G strains have been associated mainly with genital, skin, and wound infections (2, 10) in dogs and with bovine mastitis (6, 16). The naming of these strains has always been confusing and contradictory. Stafseth et al. (20) first used the name "Streptococcus canis" to designate dog strains belonging to group C. However, these strains had a characteristic carbohydrate fermentation pattern which was found later only in animal group G strains (2). Widely used veterinary textbooks (4,5) refer to group G strains from dogs as "Streptococcus canis," but this name has never been accepted officially.Recent nucleic acid hybridization and cell wall composition studies (13) have shown that human large-colony group G strains are closely related to group L strains, the Phemolytic group C organism "Streptococcus equisimilis," and a-hemolytic group C strains isolated from cases of bovine mastitis and polyarthritis in lambs. Similar observations led to an emended description of Streptococcus dysgalactiae (9) which fits these animal group C P-hemolytic " S . equisimilis," group C a-hemolytic S . dysgalactiae, and group L strains, as well as human group C "S. equisimilis," group L, and group G strains. The older description of S . dysgalactiae given in Bergey 's Manual of Determinative Bacteriology, 8th ed. (7), applied only to the animal ahemolytic group C strains.However, it has been found that several characteristics of animal group G strains in our collection did not correspond to the characteristics given in the new description of S . dysgalactiae. The...

Prevalence and Characteristics of Streptococcus canis Strains Isolated from Dogs and Cats

“…Our results are lower than the observations of Lammler et al (1987), Vieira and Castro (1994) and Facklam (2002), who reported CAMP-like reaction in 74.1%, 100% and 95% of strains, respectively. On the contrary, other studies have reported the absence of CAMP-like reactions (Clark et al 1984;Devriese et al 1986). …”

“…There was one prevalent biotype among the isolated strains which produced phosphatase, leucine amidopeptidase, arginine dihydrolase, alpha-D-and beta-D-galactosidase and fermented lactose and ribose. Results from the biochemical tests that are typically variable (including pyrrolidonylarylamidase, alpha-D-and beta-D-galactosidase, beta-D-glucuronidase, and acidification of lactose and trehalose) were generally within the range of proportions reported for S. canis by other researchers (Clark et al 1984;Devriese et al 1986;Efstratiou et al 1994;Vieira and Castro 1994;Soedarmanto and Lammler 1996). Only 16.3% of S. canis strains were positive for esculin hydrolysis, which is in contrast to the results of Devriese et al (1986) and Vieira and Castro (1994), who found 100% and 90% of strains positive, respectively.…”

“…Results from the biochemical tests that are typically variable (including pyrrolidonylarylamidase, alpha-D-and beta-D-galactosidase, beta-D-glucuronidase, and acidification of lactose and trehalose) were generally within the range of proportions reported for S. canis by other researchers (Clark et al 1984;Devriese et al 1986;Efstratiou et al 1994;Vieira and Castro 1994;Soedarmanto and Lammler 1996). Only 16.3% of S. canis strains were positive for esculin hydrolysis, which is in contrast to the results of Devriese et al (1986) and Vieira and Castro (1994), who found 100% and 90% of strains positive, respectively. On the other hand, Efstratiou et al (1994) described only 40% of strains as esculin positive and all positive reactions were reported as delayed, which might be responsible for some of the discrepancy.…”

“…This is in contrast to the findings of Knotek et al (2001), who found 7.5% of samples positive for S. canis. All beta-haemolytic streptococci of the Lancefield serological group G isolated in this study belong to the species S. canis, as defined by Devriese et al (1986). No significant differences in biochemical properties between S. canis strains isolated from healthy animals and from animals with proceeding infection were observed.…”

Antibiotic Resistance in the Environment, with Particular Reference to MRSA

“…Although methicillin is not generally used in treatment of cows, MRSA is increasing in its significance as a cause of bovine mastitis (Bernabé et al, 2005;Turutoglu et al, 2006). Acquisition of MRSA may occur through direct contact with humans: one outbreak of mastitis has been attributed to contact with a farm worker (Devriese et al, 1986), and more recent empirical evidence concurs with this (Fox et al, 1991;Roberson et al, 1994). However, this is slightly contentious as evidence to the contrary suggests that transmission between humans and cows is rare (Kapur et al, 1995;Lopes et al, 1990) due to the host-specificity of S. aureus clones (Smith et al, 2005).…”