From: Impact of foot-and-mouth disease on mastitis and culling on a large-scale dairy farm in Kenya
Variable | Clinical mastitis | Culling | ||||
---|---|---|---|---|---|---|
HR (95%CI) | P -value | HR (95% CI) | P -value | |||
FMD | ||||||
Case | 2.9 (0.97, 8.9) | 0.057 | 1.7 (0.88, 3.1) | 0.12 | ||
Non-case | Baseline | - | Reference | - | ||
Age aAge category Age category | ||||||
1.5- < 2.0 y | Baseline | - | −28- <227d | Baseline | - | |
2.0- < 2.8 y | 0.61 (0.12, 3.0) | 0.54 | 227- < 577d | 0.29 (0.07, 1.2) | 0.090 | |
2.8- < 3.5 y | 0.77 (0.16, 3.7) | 0.75 | 577- < 974d | 0.93 (0.32, 2.7) | 0.89 | |
3.5- < 4.3 y | 0.64 (0.12, 3.3) | 0.60 | 974- < 1363d | 0.76 (0.21, 2.7) | 0.76 | |
4.3-9.7 y | 2.6 (0.45, 15.1) | 0.29 | 1364-3543d | 1.5 (0.34, 6.3) | 0.60 | |
Lactation stage | 0.45 (0.24, 0.83) | 0.010 | ||||
Non-lactating | - | - | ||||
Early lactation (<0-100d) | - | - | ||||
Mid lactation (101-250d) | - | - | ||||
Late lactation (>250d) | - | - | ||||
Dry | - | - | ||||
Breed b | 1.4 | 0.031 | - | - | ||
Tick borne disease (last 12 months) | ||||||
Yes | - | - | 3.2 (1.8, 5.9) | <0.0001 | ||
No | - | - | Baseline | |||
Parity | ||||||
0 | Baseline | - | Baseline | |||
1 | 11.3 (2.5, 51.2) | 0.002 | 2.8 (0.91, 8.4) | 0.074 | ||
2 | 9.8 (1.7, 55.9) | 0.010 | 0.66 (0.16, 2.6) | 0.55 | ||
3 | 4.6 (0.65, 32.6) | 0.13 | 2.4(0.60, 9.8) | 0.21 | ||
≥4 | 8.1 (1.2, 55.8) | 0.033 | 0.88 (0.16, 5.0) | 0.89 | ||
Time varying interactions | ||||||
FMD | 0.43 | 0.016 | - | - | ||
Lactation stage | - | - | 2.0 (1.4, 2.6) | <0.0001 |