Table 2 Association of different risk factors with E. coli O157:H7 occurrence at animal level
Variable | Total animals examined | Total animals positive (%) | Fisher’s exact test | p-value |
|---|---|---|---|---|
Sex | ||||
 Male | 138 | 7 (4.7) | 0.63 | 1.0 |
 Female | 12 | 0 | ||
Age | ||||
 3 years | 25 | 2 (1.3) | 4.7 | 0.04 |
 4–6 years | 81 | 1 (0.7) | ||
  ≥ 7 years | 44 | 4 (2.7) | ||
Origin | ||||
 Tula | 40 | 2 (1.3) | 5.5 | 0.36 |
 Arsi Negelle | 24 | 3 (2) | ||
 Wondogenet | 7 | 0 | ||
 Hawassa | 30 | 0 | ||
 Yirgalem | 34 | 1 (0.7) | ||
 Tikurwoha | 13 | 1 (0.7) | ||
Breed | ||||
 Crossbred | 13 | 0 (0) | 0.69 | 1.0 |
 Local (zebu) | 137 | 7 (4.7) | ||