Table 2.

Univariate linear regression analysis of OD values for bulk milk and serological status of lactating animals in serovar Dublin-infected herds (n = 61)

ELISA and parameterLPS ELISA with bulk milk (OD)GP ELISA with bulk milk (OD)
βSD (β)R2βSD (β)R2
 Seropositive cows (%)0.0300.0040.51a 0.0420.0040.61
 Cows with positive milk (%)b 0.0310.0040.530.0420.0040.62
 Mean log10 serum antibody titerc 1.4470.1730.541.9900.1950.63
GP ELISA serum
 Seropositive cows (%)0.0380.0040.600.0530.0040.72
 Cows with positive milk (%)0.0390.0040.610.0530.0040.71
 Mean log10 serum antibody titer1.7940.1810.622.4710.1920.73
  • a All univariate linear regression models were significant at P < 0001 .

  • b Milk production of all seropositive cows in the herd (in kilograms) divided by total milk volume of the herd (in kilograms).

  • c Sum of log10 serum antibody titer for all seropositive lactating cows in the herd divided by number of lactating cows in the herd.