Table 4.
Distribution of biosecurity characteristics in 559 Norwegian dairy herds by DD category (DD+/DD−) stratified on housing system
| Biosecurity—contact with other herds | Free stalls | Tie stalls | ||
|---|---|---|---|---|
| DD+ (n = 108) | DD− (n = 281) | DD+ (n = 5) | DD− (n = 165) | |
| n (%)b | n (%)b | n (%)b | n (%)b | |
| Staff working in other cattle herds | ||||
| No | 59 (55.1) | 150 (53.4) | 3 (60.0) | 72 (44.2) |
| Yes | 46 (43.0) | 130 (46.3) | 2 (40.0) | 91 (55.8) |
| Uncertain | 2 (1.9) | 1 (0.3) | 0 | 0 |
| Missing | 1 | 0 | 0 | 2 |
| Purchased cattle the last 5 yearsa | ||||
| 0 animals | 23 (21.3) | 101 (35.9) | 0 | 54 (32.7) |
| 1–2 animals | 12 (11.1) | 31 (11.0) | 2 (40.0) | 32 (19.4) |
| 3–4 animals | 6 (5.6) | 21 (7.5) | 0 | 19 (11.5) |
| 5–11 animals | 19 (17.6) | 49 (17.4) | 2 (40.0) | 34 (20.6) |
| 12–27 animals | 20 (18.5) | 43 (15.3) | 1 (20.0) | 17 (10.3) |
| 28–52 animals | 15 (13.9) | 23 (8.2) | 0 | 7 (4.2) |
| ≥53 animals | 13 (12.0) | 13 (4.6) | 0 | 2 (1.2) |
| Missing | 0 | 0 | 0 | 0 |
| Require claw health documentation before purchase | ||||
| No | 44 (55.7) | 81 (48.8) | 0 | 57 (56.4) |
| Yes | 28 (35.4) | 79 (47.6) | 4 (100) | 39 (38.6) |
| Uncertain | 7 (8.9) | 6 (3.6) | 0 ( | 5 (5.0) |
| Missing | 29 | 115 | 1 | 64 |
| Claw health documentation required on | ||||
| Individual level | 7 (25.0) | 13 (16.9) | 0 | 9 (23.1) |
| Herd level | 11 (39.3) | 27 (35.1) | 1 (25.0) | 10 (25.6) |
| Both individual cow and herd level | 9 (32.1) | 33 (42.8) | 3 (75.0) | 17 (43.6) |
| Uncertain | 1 (3.6) | 4 (5.2) | 0 | 3 (7.7) |
| Missing | 80 | 204 | 1 | 126 |
| Purchased animals are in quarantine | ||||
| No | 73 (91.2) | 152 (92.7) | 4 (100) | 97 (96.0) |
| Yes | 6 (7.5) | 11 (6.7) | 0 | 4 (4.0) |
| Uncertain | 1 (1.3) | 1 (0.6) | 0 | 0 |
| Missing | 28 | 117 | 1 | 64 |
| House animals from other herds | ||||
| No | 103 (98.1) | 276 (98.6) | 5 (100) | 159 (97.0) |
| Yes | 2 (1.9) | 4 (1.4) | 0 | 5 (3.0) |
| Missing | 3 | 1 | 0 | 1 |
| Use shared pasture | ||||
| No | 80 (79.2) | 189 (71.3) | 3 (60.0) | 104 (65.8) |
| Yes | 21 (20.8) | 76 (28.7) | 2 (40.0) | 54 (34.2) |
| Missing | 7 | 16 | 0 | 7 |
| Shared transportation to pasture | ||||
| No | 96 (96.0) | 250 (94.3) | 3 (60.0) | 152 (96.2) |
| Yes | 4 (4.0) | 15 (5.7) | 2 (40.0) | 6 (3.8) |
| Missing | 8 | 16 | 0 | 7 |
| Biosecurity barrier in entrance of barn | ||||
| No | 6 (5.6) | 11 (3.9) | 1 (20.0) | 29 (17.6) |
| Yes | 102 (94.4) | 269 (95.7) | 4 (80.0) | 136 (82.4) |
| Uncertain | 0 | 1 (0.4) | 0 | 0 |
| Missing | 0 | 0 | 0 | 0 |
| Facilities in biosecurity barrier: | ||||
| Hand wash in clean area | ||||
| No | 31 (31.6) | 66 (25.1) | 1 (25.0) | 45 (34.6) |
| Yes | 67 (68.4) | 197 (74.9) | 3 (75.0) | 85 (65.4) |
| Missing | 10 | 18 | 1 | 35 |
| Hand wash in unclean area | ||||
| No | 26 (26.8) | 92(35.7) | 1 (33.3) | 48 (37.5) |
| Yes | 71 (73.2) | 166 (64.3) | 2 (67.7) | 80 (62.5) |
| Missing | 11 | 23 | 2 | 37 |
| Clearly visible border between clean and unclean area | ||||
| No | 29 (29.3) | 71 (26.9) | 2 (50.0) | 30 (22.9) |
| Yes | 70 (70.7) | 193 (73.1) | 2 (50.0) | 101 (77.1) |
| Missing | 9 | 17 | 1 | 34 |
| Grid on each side of border between clean and unclean area | ||||
| No | 70 (73.7) | 186 (71.5) | 3 (75.0) | 99 (77.3) |
| Yes | 25 (26.3) | 74 (28.5) | 1 (25.0) | 29 (22.7) |
| Missing | 13 | 21 | 1 | 37 |
| Boots for visitors | ||||
| No | 1 (1.0) | 3 (1.1) | 0 | 1 (0.7) |
| Yes | 101 (99.0) | 264 (98.9) | 4 (100) | 135 (99.3) |
| Missing | 6 | 14 | 1 | 29 |
| Coveralls for visitors | ||||
| No | 1 (1.0) | 2 (0.8) | 0 | 2 (1.5) |
| Yes | 101 (99.0) | 263 (99.2) | 4 (100) | 133 (98.5) |
| Missing | 6 | 16 | 1 | 30 |
| Transport to slaughterhouse: | ||||
| The driver is never inside the barn | 35 (32.4) | 101 (35.9) | 2 (40.0) | 70 (42.4) |
| The driver is fetching the animals in restricted area inside the barn | 23 (21.3) | 55 (19.6) | 2 (40.0) | 9 (5.5) |
| Animals are fetched by the driver from the barn | 24 (22.2) | 43 (15.3) | 0 | 62 (37.6) |
| The transport is parked partially inside the barn | 6 (5.6) | 20 (7.1) | 1 (20.0) | 4 (2.4) |
| Combination of the alternatives | 8 (7.4) | 21 (7.5) | 0 | 6 (3.6) |
| None of the alternatives | 12 (11.1) | 41 (14.6) | 0 | 14 (8.5) |
| Missing | 0 | 0 | 0 | 0 |
aData from NDHRS
bMissing not included in %