TABLE 2.
Percentages of samples from cattle farms positive for EHEC virulence markers
| Production type and farm | % of samples with virulence marker
|
% EHECa | ||||
|---|---|---|---|---|---|---|
| stx1 | stx2 | stx1 and 2 | eae | ehx | ||
| Dairy | ||||||
| Calves | ||||||
| D1 | 0.8 | 1.7 | 3.3 | |||
| D2 | 9.7 | 6.5 | 12.9 | 9.7 | 19.4 | 9.7 |
| Mean | 3.8 | 3.3 | 6.6 | 3.3 | 6.6 | 3.3 |
| No calves | ||||||
| D3 | 5.0 | 0.8 | ||||
| D4 | 1.7 | |||||
| D5 | 2.4 | 5.7 | 5.7 | 5.7 | 0.8 | 0.8 |
| Mean | 3.0 | 2.3 | 3.0 | 2.3 | 0.3 | 0.3 |
| Mean | 3.3 | 2.7 | 4.3 | 2.7 | 2.7 | 1.4 |
| Feedlot | ||||||
| Weanling | ||||||
| F1 | 1.7 | 1.7 | ||||
| F2 | 2.5 | 3.3 | ||||
| Mean | 2.1 | 2.5 | ||||
| Yearling | ||||||
| F3 | 2.5 | 0.8 | ||||
| F4 | 0.8 | 2.5 | 1.7 | 1.7 | 1.7 | |
| Mean | 1.7 | 1.3 | 1.3 | 0.8 | 0.8 | |
| Mean | 1.9 | 1.9 | 0.6 | 0.4 | 0.4 | |
| Range | ||||||
| Extensive | ||||||
| R1 | 0.8 | 1.7 | 1.7 | |||
| R2 | 3.3 | 2.5 | ||||
| Mean | 0.4 | 2.5 | 2.1 | |||
| Intensive | ||||||
| R3 | 4.0 | 9.5 | 4.8 | 0.8 | 6.3 | 2.4 |
| R4 | 2.4 | 6.5 | 13.8 | 7.3 | 16.3 | 7.3 |
| Mean | 3.2 | 8.0 | 9.2 | 4.0 | 11.2 | 4.8 |
| Mean | 1.6 | 4.3 | 5.9 | 2.0 | 6.7 | 2.4 |
| Total | 1.6 | 2.9 | 4.0 | 1.8 | 3.3 | 1.4 |
a
Percentage of samples from which a putative EHEC strain was isolated.