Table 6 Comparisons of culling risks (%) for served sows between either herd groups or weaning-to-first-service interval (WSI) groups, and the relative risk ratios for culling at different parities estimated by the models
From: Culling in served females and farrowed sows at consecutive parities in Spanish pig herds
Parity 1 | Parity 2 | Parity 3 | Parity 4 | Parity 5 | Parity 6 | |
|---|---|---|---|---|---|---|
Final model No. | Model 2 | Model 3 | Model 4 | Model 4 | Model 4 | Model 4 |
Groups | Culling risks (± SE), % | |||||
Herd groups | ||||||
High-performing herds | – | 4.1 (0.39)b | 5.3 (0.42) | 5.3 (0.45)b | 6.8 (0.53)b | 7.7 (0.64)b |
Ordinary herds | – | 5.2 (0.29)a | 6.1 (0.30) | 6.8 (0.36)a | 8.2 (0.41)a | 10.0 (0.53)a |
WSI groups | ||||||
0–6 days | 3.6 (0.19)b | 3.5 (0.19)b | 4.3 (0.20)b | 4.5 (0.22)b | 5.9 (0.26)b | 7.0 (0.33)b |
7 days or more | 5.8 (0.32)a | 6.1 (0.40)a | 7.5 (0.44)a | 8.1 (0.51)a | 9.5 (0.59)a | 10.9 (0.76)a |
Groups | Relative risk ratio for culling (95% CI) | |||||
Herd groups | ||||||
High-performing herds | – | NA | 0.88 (0.73–1.05) | 0.79 (0.65–0.95) | 0.82 (0.69–0.98) | 0.77 (0.64–0.93) |
Ordinary herds | – | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
WSI groups | ||||||
0–6 days | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
7 days or more | 1.60 (1.50–1.72) | NA | 1.75 (1.61–1.91) | 1.81 (1.65–1.99) | 1.63 (1.47–1.80) | 1.56 (1.39–1.75) |