Table 2.
Descriptive statistics of variables in survey questionnaires found to be unconditionally associated with ear necrosis status of the farm (P < 0.2)
| Variables | Case mean (SD) | Control mean (SD) | P-value |
|---|---|---|---|
| Minimum weaning age (days) | 16.9 (1.15) | 27 (1.72) | 0.05 |
| Average weaning age (days) | 20.7 (0.99) | 28.6 (3.31) | 0.06 |
| Number of sows on farm | 871.1 (287.07) | 357.4 (121.15) | 0.2 |
| Zinc level in feed (ppm) | 191.3 (41.7) | 1009.8 (465.7) | 0.2 |
| Downtime after washing (days) | 1.9 (0.32) | 1.1 (0.4) | 0.2 |
SD — standard deviation.