Table 2.
Recovery and detection limits for bacterial pathogens in a dairy wastewater determined by qPCR after spiking
| Target organism | Wastewater titer range after spiking (log10 CFU ml−1 wastewater) | Range of recovery values (%) | Mean recovery (%)a | qPCR detection limit (no. of cells ml−1) |
|---|---|---|---|---|
| C. jejuni | 3.4–8.4 | 41–836 | 326 | 768 |
| E. coli | ||||
| stx1 | 3.2–8.2 | 38–120 | 72 | 1,229 |
| stx2 | 3.2–8.2 | 54–238 | 121 | 232 |
| eaeA | 2.2–8.2 | 41–117 | 75 | 140 |
| L. monocytogenes | 3.5–8.5 | 45–127 | 81 | 410 |
| M. avium subsp. paratuberculosis | 1.5–6.5 | 25–52 | 37 | 16 |
| S. enterica | 3.3–8.3 | 13–133 | 56 | 325 |
| Y. pseudotuberculosis | 3.2–8.2 | 126–179 | 160 | 234 |
a
Data represent mean values as determined by spiking triplicate wastewater samples with pathogens at several titer levels.