Factor | Category | IRR (95% CI) | P-value |
---|---|---|---|
Farmers age | >45 | 0.81 (0.71-0.93) | 0.003 |
≤45 | 1.0 | - | |
Production zone | Mountain | 0.73 (0.62-0.85) | <0.001 |
Hill | 0.91 (0.75-1.09) | 0.32 | |
Valley | 1.0 | - | |
Dairy herd replacement system | Buying cows | 1.27 (1.08-1.50) | 0.004 |
Other†| 1.0 | - | |
Prophylactic measures taken when purchasing a dairy cow | Never purchase | 0.83 (0.71-0.98) | 0.02 |
Other‡ | 1.0 | - | |
Milking system | Bucket | 1.21 (1.04-1.41) | 0.01 |
Pipeline | 1.0 | - | |
Teat cleaning material | Paper towel | 1.19 (1.04-1.37) | 0.01 |
Other§ | 1.0 | - | |
Feeding system | Cow specific | 0.81 (0.66-0.99) | 0.04 |
Other¶ | 1.0 | - | |
Intervention at each calving | No | 0.87 (0.75-0.99) | 0.04 |
Yes | 1.0 | - |