Factor | Level | Crude disease prevalence per 100 animal years at risk | Cumulative disease incidence rate (%) |
Production environment | Low-stress (n = 386) | 21.87 ± 5.95 | 5.59 ± 1.46 |
High-stress (n = 408) | 33.43 ± 6.62 | 8.46 ± 1.63 | |
Mean difference | 11.56 | 2.88 | |
p-value | 0.1945 | 0.1899 | |
Farm (environment) | Low-stress |
|
|
Positive deviants (n = 15) | 10.13 ± 11.67 | 2.74 ± 2.87 | |
Typical (n = 371) | 33.61 ± 2.35 | 8.44 ± 0.58 | |
Mean difference | 23.48 | 5.70 | |
p-value | 0.0489 | 0.0522 | |
High-stress |
|
| |
Positive deviants (n = 12) | 9.56 ± 13.05 | 2.58 ± 3.21 | |
Typical (n = 396) | 57.30 ± 2.27 | 14.34 ± 0.56 | |
Mean difference | 47.74 | 11.76 | |
p-value | 0.0003 | 0.0003 | |
Farm | Positive deviants (n = 27) | 9.85 ± 8.75 | 2.66 ± 2.15 |
Typical (n = 767) | 45.46 ± 1.63 | 11.39 ± 0.40 | |
Mean difference | 35.61 | 8.73 | |
p-value | <0.0001 | <0.0001 |