Fig. 1
Characteristics of 19 studied herds and ELISA results during implementation of MAP control measures
| Herd | Number of lactating cows in the herd | Control period in years | Initial percentage of EPAY | Final percentage of EPAY | Average percentage of retested EPAY |
|---|---|---|---|---|---|
| 1 | 470 | 4 | 12.86 | 3.88 | 16.84 |
| 2 | 284 | 6 | 0.82 | 0 | 0 |
| 3 | 330 | 6 | 9.42 | 1.11 | 0 |
| 4 | 432 | 3 | 2.20 | 2.96 | 0 |
| 5 | 535 | 4 | 3.36 | 2.00 | 8.33 |
| 6 | 920 | 6 | 7.65 | 2.32 | 3.20 |
| 7 | 423 | 6 | 2.53 | 1.53 | 4.79 |
| 8 | 390 | 5 | 7.04 | 1.90 | 8.23 |
| 9 | 435 | 6 | 10.04 | 0.90 | 8.16 |
| 10 | 570 | 4 | 2.90 | 1.24 | 23.67 |
| 11 | 590 | 4 | 7.34 | 2.76 | 41.31 |
| 12 | 600 | 7 | 10.66 | 0.20 | 22.28 |
| 13 | 730 | 3 | 3.80 | 1.73 | 0 |
| 14 | 613 | 3 | 11.42 | 4.65 | 21.17 |
| 15 | 550 | 5 | 8.11 | 2.20 | 27.33 |
| 16 | 760 | 6 | 2.05 | 1.95 | 13.13 |
| 17 | 188 | 4 | 9.22 | 1.49 | 9.40 |
| 18 | 110 | 7 | 17.20 | 3.45 | 29.21 |
| 19 | 220 | 7 | 23.05 | 7.57 | 36.39 |
Data and results of χ2 test for a trend of decreasing number of ELISA-positive animals tested per year during the control period
| Herd | Total number of tested animals | Total number of ELISA-positive animals | Percentage of ELISA-positive animals | Trend |
|---|---|---|---|---|
| 1 | 1,425 | 117 | 8.21 | P < 0.01 |
| 2 | 1,341 | 12 | 0.89 | P > 0.05 |
| 3 | 2,271 | 88 | 3.87 | P < 0.01 |
| 4 | 871 | 20 | 2.30 | P > 0.05 |
| 5 | 1,922 | 47 | 2.45 | P > 0.05 |
| 6 | 4,852 | 195 | 4.02 | P < 0.01 |
| 7 | 2,764 | 59 | 2.13 | P > 0.05 |
| 8 | 2,164 | 84 | 3.88 | P < 0.01 |
| 9 | 2,463 | 113 | 4.59 | P < 0.01 |
| 10 | 2,462 | 58 | 2.36 | P < 0.05 |
| 11 | 3,032 | 130 | 4.29 | P < 0.01 |
| 12 | 3,231 | 105 | 3.25 | P < 0.01 |
| 13 | 2,168 | 54 | 2.49 | P < 0.05 |
| 14 | 1,492 | 125 | 8.38 | P < 0.01 |
| 15 | 2,357 | 100 | 4.24 | P < 0.01 |
| 16 | 3,700 | 93 | 2.51 | P > 0.05 |
| 17 | 736 | 30 | 4.08 | P < 0.01 |
| 18 | 922 | 68 | 7.38 | P < 0.01 |
| 19 | 1,960 | 189 | 9.64 | P < 0.01 |
| Total | 42,133 | 1,687 | ||