From: Seroprevalence and risk factors of Brucella ovis in domestic sheep in Wyoming, USA
Risk Factor | N | Seroprevalencea | Odds Ratio (95% CI) | P value |
---|---|---|---|---|
Regionb | ||||
 Southeast | 17 | 5.9% (1/17) | Reference | – |
 Northwest | 25 | 12.0% (3/25) | 1.99 (0.21 to 60.81) | 0.575 |
 Northeast | 20 | 25.0% (5/20) | 4.67 (0.62 to 134.15) | 0.294 |
 West | 6 | 16.7% (1/6) | 3.01 (0.069 to 131.62) | 0.575 |
 South-central | 14 | 57.1% (8/14) | 17.34 (2.39 to 502.01) | 0.012 |
Flock Sizeb | ||||
 Small | 24 | 4.2% (1/24) | Reference | – |
 Very Small | 20 | 10.0% (2/20) | 2.36 (0.18 to 78.42) | 0.516 |
 Medium | 32 | 31.3% (10/32) | 9.06 (1.51 to 237.89) | 0.018 |
 Large | 6 | 83.3% (5/6) | 69.00 (5.81 to > 999.99) | < 0.001 |
Ewe-to-ram Ratio | ||||
 Medium | 9 | 44.4% (4/9) | Reference | – |
 Low | 4 | 25.0% (1/4) | 0.47 (0.01 to 6.07) | 0.587 |
 High | 4 | 75.0% (3/4) | 3.21 (0.254 to 116.89) | 0.587 |
Purchase of Outside Sheep | ||||
 No | 7 | 28.6% (2/7) | Reference | – |
 Yes | 9 | 55.6% (5/9) | 2.83 (0.35 to 32.03) | 0.340 |