Table 4.
Significant risk factors for shedding of STEC by dairy cattle
| variables class | no. of sampled cows |
no. of stx-pos. cows |
% of stx-pos. cows |
Odds- Ratio |
95%-CI | against (Odds = 1) |
sign. |
|---|---|---|---|---|---|---|---|
| days in milk | |||||||
| 51.-100.d | 175 | 44 | 25.1% | 1.73 | 0.98-3.04 | 1.-50.d | t |
| 101.-150.d | 192 | 52 | 27.1% | 1.93 | 1.11-3.35 | 1.-50.d | * |
| >350.d | 114 | 36 | 31.6% | 2.06 | 1.12-3.79 | 1.-50.d | * |
| dry cows | 182 | 50 | 27.5% | 1.67 | 0.95-2.91 | 1.-50.d | t |
| number of lactation | |||||||
| first calvers | 293 | 93 | 31.7% | 1.74 | 1.22-2.47 | >3 completed lactations | ** |
| first calvers | 293 | 93 | 31.7% | 1.51 | 1.07-2.11 | 2-3 completed lactations | * |
| somatic cell count (/ml milk) | |||||||
| <100,000 | 1028 | 279 | 27.1% | 1.57 | 1.18-2.10 | >100,000 | ** |
| protein content in milk (%) | |||||||
| 3.00-3.80 | 906 | 220 | 24.3% | 1.80 | 1.06-3.08 | <3.00 | * |
| >3.80 | 198 | 54 | 27.3% | 2.30 | 1.18-4.48 | <3.00 | * |
| content in urea in milk (in mg/l) | |||||||
| <150 | 580 | 144 | 24.8% | 0.69 | 0.45-1.06 | 150-300 | t |
| BCS | |||||||
| 3.50-5.00 | 318 | 81 | 25.5% | 1.92 | 1.22-3.04 | 1.00-3.25 | * |
| presence of a Super-Shedder | |||||||
| yes | 1071 | 323 | 30.2% | 2.63 | 1.90-6.64 | no | *** |
*** p-value < 0.001
**: p-value < 0.01
*: p-value < 0.05
t: tendency, p-value < 0.1
<: smaller than
>: bigger than
d: day, %: percentage
CI: confidence interval
sign.: significance, p-value
BCS: body condition score according to Edmonson et al. [51]