Table 1 Herd characteristics for study farms and farms participating in the Alberta Johne’s Disease Initiative (AJDI, n (%))
From: Calves shedding Mycobacterium avium subspecies paratuberculosis are common on infected dairy farms
Study participants ( n = 18) | Other AJDI farms ( n = 342) | |
|---|---|---|
Herd size | 0.691 | |
<50 | 0 (−) | 9 (3) |
50 – 99 | 2 (11) | 102 (30) |
100 - 149 | 8 (44) | 130 (38) |
150 – 199 | 3 (17) | 48 (14) |
>199 | 4 (22) | 53 (15) |
History of clinical Johne’s disease | 0.031 | |
JD has been observed | 10 (56) | 98 (29) |
Don’t know | 4 (22) | 74 (22) |
JD has never been observed | 4 (22) | 170 (49) |
Positive environmental samples | < 0.011 | |
0 positives | 2 (11)2 | 188 (55) |
1-3 positives | 9 (50) | 84 (25) |
4-6 positives | 7 (39) | 70 (20) |