Table 2 Cross classification of biosecurity or management variables and serological Leptospira results using the microscopic agglutination test at herd level using a cut-off level of 1:100 among 69 dairy herds in southern Chile, 2011
Variables | Category | MAT results | |
|---|---|---|---|
| Â | Â | No. seropos (%) | No. seroneg (%) |
Abortions | yes | 18 (26) | 5 (7.2) |
| Â | no | 34 (49) | 12 (17) |
Adult cows in contact with calves | yes | 27 (39) | 10 (14) |
| Â | no | 25 (36) | 7 (10) |
Adult cows in contact with heifers | yes | 34 (49) | 9 (13) |
| Â | no | 18 (26) | 8 (12) |
Calve rearing system | natural | 25 (36) | 11(16) |
| Â | artificial | 27 (40) | 6 (8.7) |
Cleaning the designated calving area | yes | 5(7.2) | 4 (5.8) |
| Â | no | 47 (68) | 13 (8.7) |
Horses on the farm | yes | 12 (17) | 1 (1.5) |
| Â | no | 40 (58) | 16 (23) |
Leptospira vaccination | yes | 3 (2.1) | 0 (0) |
| Â | no | 49 (33) | 17 (25) |
Pigs on the farm | yes | 15 (22) | 4 (5.8) |
| Â | no | 37 (54) | 13 (19) |
Presence of dogs | yes | 43 (62) | 11 (16) |
| Â | no | 9 (13) | 6 (8.7) |
Purchase and/or introduction of new cattle | yes | 31 (45) | 9 (13) |
| Â | no | 21 (30) | 8 (12) |
Rodent control | yes | 39 (57) | 12 (17) |
| Â | no | 13 (19) | 5 (7.2) |
Rodents on the farm | yes | 39 (57) | 7 (10) |
| Â | no | 13 (18) | 10 (15) |
Sheep or goats on the farm | yes | 11 (16) | 5 (7.3) |
| Â | no | 41 (59) | 12 (17) |
Use of designated calving area | yes | 33 (48) | 4 (5.6) |
| Â | no | 19 (28) | 13 (19) |
Wild boars | yes | 8 (12) | 1 (1.4) |
| Â | no | 44 (64) | 16 (23) |