Table 6.
Factors associated with dairy herd status for BVD and BoHV1 using logistic regression analysis. Dependent variables included BVD herd status, BoHV-1 herd status, and evidence of recent viral circulation
| Dependent variable | Independent variable | Odds ratio | Confidence interval (95 %) | P value | |
|---|---|---|---|---|---|
| BVD herd status | Purchased bulls in the herd vs. all homebred | 3.45 | 1.2 | 9.9 | 0.02 |
| POSITIVE vs. NEGATIVE | Region 2 vs. Region 1 | 4.61 | 1.74 | 12.17 | 0.002 |
| 66–99 cows vs. 31–65 cows | 4.06 | 1.15 | 14.34 | 0.029 | |
| Vaccinated vs. no vaccinated | 8.78 | 3.13 | 24.62 | 0 | |
| Recent circulation viral vs. no recent circulation | 16.55 | 3.31 | 82.68 | 0.001 | |
| Vasectomized bulls in the herd vs. no vasectomized bullsa | 3.77 | 0.93 | 15.31 | 0.064 | |
| IBR herd status | >1 bull vs. 1 bull | 2.13 | 1.08 | 4.19 | 0.027 |
| POSITIVE vs. NEGATIVE | Region 1 vs. Region 2b | 1.86 | 0.96 | 3.62 | 0.064 |
| IBR recent circulation viral | Region 1 vs. Region 2 | 2.8 | 1.11 | 7.01 | 0.028 |
| Yes vs. No | >99 cows vs. 31–65 cows | 6.71 | 1.44 | 31.03 | 0.015 |
| Purchased bulls in the herd vs. all homebred | 3.9 | 1.07 | 14.22 | 0.039 | |
| IBR overall Bull status | >1 bull vs. 1 bullc | 1.83 | 0.95 | 3.54 | 0.068 |
| Positive vs. negative | Purchased bulls in the herd vs. all homebred | 2.73 | 1.28 | 5.82 | 0.009 |
| >99 cows vs. 31–65 cows | 1.80 | 1.19 | 2.75 | 0.005 | |
a,b,cIncluded for the purposes of highlighting a trend