Parameter | Change in daily production after challenge (kg of milk)^{b} | t | Probable association^{c} | |
---|---|---|---|---|

Estimate | SE | |||

Intercept | −0.9 | 2.11 | −0.41 | 0.702 |

Variables | ||||

J5 vaccination | 6.7 | 3.33 | 2.00 | 0.102 |

J5-specific antibody titer^{d} | 2.8 | 1.43 | 1.93 | 0.111 |

↵

*a*For the overall linear regression model,*R*^{2}= 0.50 and*P*= 0.18.↵

*b*The change in daily milk production was calculated by taking the difference between the mean of the 8 days before intramammary*E. coli*challenge and the mean of the 7 days following challenge.↵

*c*Values indicate the probability that the parameter is significantly related to the change in milk production; lower values indicate greater probability. Values were calculated by comparison of the calculated*t*value to the critical*t*value. The SAS program indicates this comparison by the shorthand notation “Pr >*t*,” where Pr is probability.↵

*d*Ratio of J5-specific IgG1 antibody to IgG2 antibody. Serum antibody titers were measured just after calving.