Table 4.
Prevalence of the different microorganisms isolated from the milk of mammary quarters of dairy cows with clinical mastitis and identified using MALDI-TOF estimated using random meta-analyses conducted on the raw data from 43,924 samples using 8 datasets (Canada, USA and Brazil). Only microorganisms with prevalence ≥0.1% are reported.
| Microorganism | Prevalence (95% CI) | 95% Prediction Interval a |
|---|---|---|
| Escherichia coli | 11.0 (8.1–14.3) | 4.5–19.9 |
| Streptococcus uberis | 8.5 (5.3–12.2) | 1.4–20.4 |
| Streptococcus dysgalactiae | 7.8 (4.9–11.5) | 1.1–19.8 |
| Staphylococcus aureus | 7.8 (4.4–11.9) | 0.4–22.6 |
| Klebsiella pneumoniae | 5.6 (3.4–8.2) | 1.0–13.2 |
| Staphylococcus chromogenes | 2.3 (0.5–5.3) | 0.0–14.0 |
| Serratia marcescens | 1.0 (0.5–1.7) | 0.0–3.4 |
| Trueperella pyogenes | 0.9 (0.1–2.2) | 0.0–6.0 |
| Corynebacterium bovis | 0.9 (0.1–2.1) | 0.0–5.9 |
| Staphylococcus haemolyticus | 0.7 (0.1–1.8) | 0.0–4.2 |
| Unspeciated b Staphylococcus | 0.7 (0.0–2.8) | 0.0–10.3 |
| Staphylococcus simulans | 0.6 (0.4–0.8) * | 0.1–1.2 |
| Staphylococcus sciuri c | 0.6 (0.1–1.6) | 0.0–4.4 |
| Unspeciated b Corynebacterium | 0.6 (0.1–1.4) | 0.0–3.8 |
| Lactococcus garvieae | 0.6 (0.1–1.3) | 0.0–2.9 |
| Unspeciated b Bacillus | 0.6 (0.0–2.5) | 0.0–9.4 |
| Staphylococcus xylosus | 0.5 (0.0–1.6) | 0.0–5.4 |
| Lactococcus lactis | 0.5 (0.0–1.4) | 0.0–4.1 |
| Streptococcus agalactiae | 0.4 (0.0–2.0) | 0.0–7.6 |
| Unspeciated b Streptococcus | 0.4 (0.0–1.1) | 0.0–3.5 |
| Enterobacter cloacae | 0.3 (0.2–0.4) | 0.2–0.4 |
| Streptococcus equinus | 0.3 (0.1–0.6) | 0.0–1.2 |
| Staphylococcus epidermidis | 0.3 (0.0–1.2) | 0.0–3.8 |
| Aerococcus viridans | 0.3 (0.0–1.2) | 0.0–4.1 |
| Enterococcus saccharolyticus | 0.3 (0.0–1.0) | 0.0–2.4 |
| Candida rugosa d | 0.3 (0.0–0.9) | 0.0–2.6 |
| Klebsiella oxytoca | 0.3 (0.0–0.8) | 0.0–1.8 |
| Enterococcus faecium | 0.3 (0.0–0.8) | 0.0–2.0 |
| Pasteurella multocida | 0.3 (0.0–0.7) * | 0.0–1.5 |
| Candida krusei d | 0.2 (0.0–0.7) * | 0.0–2.1 |
| Streptococcus gallolyticus | 0.2 (0.0–0.7) | 0.0–1.8 |
| Staphylococcus saprophyticus | 0.2 (0.0–0.6) | 0.0–1.7 |
| Streptococcus lutetiensis | 0.2 (0.0–0.5) * | 0.0–1.1 |
| Bacillus pumilus | 0.2 (0.0–0.5) | 0.0–1.3 |
| Unspeciated b Prototheca | 0.2 (0.0–0.5) | 0.0–1.3 |
| Staphylococcus hominis | 0.1 (0.0–0.4) | 0.0–1.1 |
| Enterococcus faecalis | 0.1 (0.0–0.3) * | 0.0–0.8 |
| Pseudomonas aeruginosa | 0.1 (0.0–0.3) * | 0.0–0.7 |
| Citrobacter koseri | 0.1 (0.0–0.3) | 0.0–1.0 |
| Corynebacterium amycolatum | 0.1 (0.0–0.3) | 0.0–0.9 |
| Staphylococcus equorum | 0.1 (0.0–0.3) | 0.0–1.1 |
| Unspeciated b Lactococcus | 0.1 (0.0–0.3) | 0.0–1.0 |
| Unspeciated b Candida | 0.1 (0.0–0.3) | 0.0–0.8 |
a Prediction interval represents the range of values that is likely to contain the value of a single new observation, in this case, the microorganism’s prevalence in a new dataset. b Microorganisms from a given genus that could not be identified to species-level by the MALDI-TOF analysis. c This microorganism was reported as Staphylococcus sciuri. However, Staphylococcus sciuri was recently reassigned to the novel genus Mammaliicoccus with Mammaliicoccus sciuri as the type species [36]. d These microorganisms were reported as Candida rugosa and Candida krusei. However, Candida rugosa was recently reassigned to the novel type species Diutina rugosa [37], and Candida krusei was reassigned to Pichia kudriavzevii [38]. * Statistically significant difference of the species-specific prevalence between countries (Canada vs. US vs. Brazil), p ≤ 0.05. See supplementary materials for details.