TABLE 1

Enumeration of and qPCR CT values for M. avium subsp. paratuberculosis bacteria in milk samples before and after a DSI process at 105°C for 3 s and calculated minimum log10 reduction

MatrixStrain/fecesEnumeration before DSI (CFU/ml)aqPCR before DSI CT valueEnumeration after DSI (CFU/ml)bqPCR after DSI CT valueMinimum log10 reductionLog10 SDc
IS900f57IS900f57
UHT skimmed milkDSM 441331.4 × 1067.7915.39<0.110.4118.027.140.06
DSM 441357.2 × 1059.0716.12<0.111.4118.176.860.05
Cow feces1.9 × 10219.14d26.61d<0.0618.51d26.12d3.300.55
UHT whole milkDSM 441333.5 × 1069.4416.12<0.111.5218.007.530.13
DSM 441351.2 × 10511.0917.37<0.114.4320.826.060.03
Cow feces1.7 × 10225.12d26.97<0.0617.72d25.27d3.440.09
Raw milkDSM 441331.2 × 1058.8415.76<0.0611.0217.566.280.11
DSM 441352.5 × 1049.9716.44<0.0613.3219.535.560.28
Cow feces5.7 × 10217.36d24.82d<0.0618.42d25.12d3.960.16
  • a Average of the enumerations before DSI of 3 trials per matrix-strain combination.

  • b Average of the enumerations after DSI of 3 trials per matrix-strain combination.

  • c Standard deviation calculated on 3 trials per matrix-strain combination.

  • d Samples diluted 10-fold before qPCR.