Table 2.
The final statistical model based on data from 545 turkey grow-outs started during 2010–2016
| Variable | Variable level | Number of grow-outs | Odds ratio | p-value | 95 % Confidence interval |
|---|---|---|---|---|---|
| Farm | Random effect | 545 | - | < 0.001 | - |
| Season | January-March (reference) | 137 | 1.00 | - | - |
| April-June | 127 | 0.60 | 0.124 | 0.31–1.15 | |
| July-September | 140 | 0.41 | 0.007 | 0.21–0.79 | |
| October-December | 141 | 0.61 | 0.117 | 0.33–1.13 | |
| Grow-out sizea | < 6000 (reference) | 83 | 1.00 | - | - |
| 6000 or more | 462 | 2.78 | 0.052 | 0.94–7.47 | |
| Feed mill | 1 (reference) | 291 | 1.00 | - | - |
| 2 | 163 | 1.32 | 0.456 | 0.63–2.77 | |
| 3 | 43 | 3.03 | 0.049 | 1.00-9.17 | |
| 4 | 27 | 0.78 | 0.734 | 0.19–3.23 | |
| 5b | 21 | 1.43 | 0.600 | 0.37–5.51 |
Only variables associated with incidence of necrotic enteritis are displayed in the table
aNumber of day-old turkeys housed on the same day on the same farm
bGrow-outs offered feeds from five different feed mills