TABLE 3

IgG antibody levels above the cutoff in serum samples from the index herd in relation to skin test status

Blood sample datea and skin test statusRelative light units × 10−3 (mean ± SD)b
MPB70 peptidePPD-BMPB70MPB83CFP10ESAT6
18 March 2014
    SICTT positive 48.1 ± 7.6 46.4 ± 6.1 49.4 ± 5.4 43.3 ± 8.2 40.5 ± 12.6 44.2 ± 11.8
    SICTT negative 30.4 ± 13.4 c 24.0 ± 13.6 c 32.7 ± 13.0 c 26.8 ± 11.0 c 24.4 ± 11.7 c 26.1 ± 14.6 c
22 May 2014
    SIT positive25.8 ± 14.016.4 +/12.7 26.4 ±12.3 26.8 ± 11.925.2 ± 13.829.3 ± 13.1
    SIT negative20.8 ± 12.812.3 ± 7.3 21.0 ± 9.5 d 22.4 ± 11.319.8 ± 8.124.6 ± 10.9
  • a SICTT was performed in March and 447 blood samples were taken 8 days after PPD-B injection, while SIT was performed in May and 207 blood samples were taken 3 days after PPD-B injection. Only RLU values above the cutoff for each antigen were analyzed.

  • b Values showing statistically significant differences between skin test-positive and -negative animals are in bold.

  • c P < 0.0001.

  • d P < 0.05.