Table 2.
Explanatory variables (P ≤ 0.25) associated with feather damage (FD) at the univariable analysis level
| Explanatory Variable | Na (%) | Coefficient | P-value |
| Farmer experience | |||
| ≤ 10 years | 19 (48.7) | Referent | |
| More than 10 years | 20 (51.3) | −14.57 | 0.1540 |
| Flock age (weeks) | 39 (100) | 0.91 | 0.0118 |
| Feather colour | |||
| White | 12 (31.6) | Referent | |
| Brown | 26 (68.4) | 14.56 | 0.1834 |
| Housing system | |||
| Single-tier/floor | 17 (43.6) | Referent | |
| Multi-tier | 22 (56.4) | −22.50 | 0.0259 |
| No. of system levels/tiers | |||
| 1 tier | 16 (42.1) | Referent | |
| 2 tiers | 8 (21.1) | −29.50 | 0.0306 |
| ≥ 3 tiers | 14 (36.8) | −21.50 | 0.0601 |
| Enrichment | |||
| Yes | 14 (36.8) | Referent | |
| No | 24 (63.2) | −25.43 | 0.0159 |
| Floor type | |||
| All litter | 8 (21.6) | Referent | |
|
Combination All wire/slatted |
21(56.8) 8 (21.6) |
8.62 42.25 |
0.4797 0.0063 |
| Proportion of litter | |||
| No litter | 8 (22.2) | Referent | |
| ≤ 1/3 litter | 9 (25.0) | −37.03 | 0.0117 |
| > 1/3 litter | 19 (52.8) | − 37.47 | 0.0041 |
| Litter type | |||
| No litter | 8 (22.2) | Referent | |
| Sawdust or sand | 7 (19.4) | −36.39 | 0.0260 |
| Wood shavings or straw | 14 (38.9) | −35.11 | 0.0130 |
| Manure | 7 (19.4) | − 36.39 | 0.0260 |
| Litter replacement | |||
| Yes | 9 (24.3) | Referent | |
| No | 20 (54.1) | −17.53 | 0.1316 |
| No litter | 8 (21.6) | 23.92 | 0.0907 |
| Raking of litter | |||
| No | 18 (51.4) | Referent | |
| Yes | 9 (25.7) | −5.78 | 0.6370 |
| No litter | 8 (22.9) | 34.14 | 0.0109 |
| Farmer visit during rear | |||
| Yes | 24 (64.9) | Referent | |
| No | 13 (35.1) | 13.91 | 0.2129 |
| Housing type in rear | |||
| Single-tier | 20 (54.0) | Referent | |
| Multi-tier | 17 (46.0) | −22.05 | 0.0326 |
| Matched perches in rear & lay | |||
| Yes | 23 (60.5) | −17.33 | 0.1016 |
| No | 15 (39.5) | Referent | |
| Matched litter in rear & lay | |||
| Yes | 20 (52.6) | Referent | |
| No | 18 (47.4) | 22.97 | 0.0242 |
| Manure belt frequency | |||
| > 3x per week | 8 (21.6) | Referent | |
| 1-2x per week | 17 (46.0) | 12.35 | 0.3376 |
| End of flock | 12 (32.4) | 35.83 | 0.0121 |
| Flock health plan in place | |||
| Yes | 11 (33.3) | Referent | |
| No | 22 (66.7) | 13.73 | 0.2174 |
| No. of diet changes | |||
| ≤ 1 change | 13 (34.2) | Referent | |
| 2–3 changes | 14 (36.8) | 18.31 | 0.1390 |
| ≥4 changes | 11 (29.0) | 20.85 | 0.1140 |
| Insoluble grit in diet | |||
| Yes | 7 (18.9) | Referent | |
| No | 30 (81.1) | 14.29 | 0.2933 |
| Insoluble fibre in diet | |||
| Yes | 13 (35.1) | Referent | |
| No | 24 (64.9) | −15.31 | 0.1672 |
| Animal by-product in diet | |||
| Yes | 6 (17.6) | Referent | |
| No | 28 (82.4) | 29.33 | 0.0463 |
| Dawn/dusk phases | |||
| Yes | 30 (76.9) | Referent | |
| No | 9 (23.1) | 18.62 | 0.1236 |
| Dawn/dusk phase method | |||
| All automatic dimmed | 15 (38.5) | Referent | |
| Gradual dim by area | 15 (38.5) | −12.80 | 0.2653 |
| No dawn/dusk | 9 (23.1) | 12.22 | 0.3557 |
| Light intensity | |||
| ≤ 10 lx | 13 (44.8) | Referent | |
| > 10 lx | 16 (55.2) | −26.78 | 0.0162 |
aNumber of flocks in which a response was provided