Table 4.
Occurrence of diarrheagenic Escherichia coli virulence genes in fecal samples of diarrheic calves from five farms in Lingwu county.
| Factor | No. samples | No. positive samples (%) | Virulence genes (no. samples) | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| stx1 | stx2 | st | lt | eaeA | aggR | ipaH | ||||
| Farm | ||||||||||
| Farm 1 | 60 | 41 (68.3) | 21 | 20 | 20 | 0 | 26 | 0 | 0 | |
| Farm 2 | 64 | 36 (56.3) | 18 | 16 | 2 | 0 | 25 | 0 | 0 | |
| Farm 3 | 59 | 36 (61.0) | 23 | 15 | 5 | 0 | 25 | 0 | 0 | |
| Farm 4 | 141 | 47 (33.3) | 35 | 20 | 4 | 0 | 30 | 0 | 0 | |
| Farm 5 | 19 | 18 (94.7) | 12 | 12 | 4 | 0 | 13 | 0 | 0 | |
| Age (days) | ||||||||||
| 1–7 | 43 | 15 (34.9) | 5 | 5 | 4 | 0 | 9 | 0 | 0 | |
| 8–21 | 122 | 32 (26.2) | 19 | 5 | 11 | 0 | 13 | 0 | 0 | |
| 22–63 | 69 | 44 (63.8) | 23 | 11 | 20 | 0 | 30 | 0 | 0 | |
| 64–180 | 109 | 87 (79.8) | 62 | 62 | 0 | 0 | 67 | 0 | 0 | |
| Season | ||||||||||
| Spring | 223 | 92 (41.3) | 59 | 39 | 11 | 0 | 61 | 0 | 0 | |
| Summer | 120 | 86 (71.7) | 50 | 44 | 24 | 0 | 58 | 0 | 0 | |
| Total | 343 | 178 (51.9) | 109 | 83 | 35 | 0 | 119 | 0 | 0 | |