Table 1.
Identification of 296 isolates of environmental streptococci recovered from bovine milk samples using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
| Number | % of total | |
|---|---|---|
| Species levela | ||
| Streptococcus uberis | 80 | 27.0 |
| Aerococcus viridans | 62 | 21.0 |
| Streptococcus dysgalactiae | 34 | 11.5 |
| Enterococcus faecalis | 20 | 6.8 |
| Lactococcus garvieae | 18 | 6.1 |
| Lactococcus lactis | 14 | 4.7 |
| Enterococcus saccharolyticus | 8 | 2.7 |
| Streptococcus parauberis | 6 | 2.0 |
| Streptococcus gallolyticus | 4 | 1.4 |
| Enterococcus faecium | 3 | 1.0 |
| Enterococcus pseudoavium | 3 | 1.0 |
| Streptococcus cristatus | 1 | 0.3 |
| Streptococcus parasanguinis | 1 | 0.3 |
| Enterococcus avium | 1 | 0.3 |
| Enterococcus casseliflavus | 1 | 0.3 |
| Enterococcus hirae | 1 | 0.3 |
| Enterococcus villorum | 1 | 0.3 |
| Arcanobacterium pluranimalium | 1 | 0.3 |
| Staphylococcus chromogenes | 1 | 0.3 |
| Genus levelb | ||
| Aerococcus spp. | 11 | 3.7 |
| Streptococcus spp. | 5 | 1.7 |
| Lactococcus spp. | 1 | 0.3 |
| Low discriminationc | ||
| Streptococcus lutetiensis/equinis | 7 | 2.4 |
| Streptococcus dysgalactiae/canis | 4 | 1.4 |
| Streptococcus gallolyticus/alactolyticus | 1 | 0.3 |
| Streptococcus gallolyticus/lutetiensis | 1 | 0.3 |
| Streptococcus pneumonia/mitis | 1 | 0.3 |
| No identificationd | 5 | 1.7 |
| Total | 296 | 100 |
aIdentification score ≥2.0; considered secure species identification.
bIdentification score ≥1.7 and <2.0; considered secure genus identification.
cIdentification score ≥2.0 for two different Streptococci species; therefore, only genus level classification was possible.
dIdentification score <1.7; considered no reliable identification.