Table 4.
Bovine viral diarrhoea (BVD) herd status for 111 herds in Ireland during 2009 (based on a comparison of bulk milk and pooled serum BVDV antibody results) in non-vaccinated herds
|
BVD herd status based on bulk milk analysis (PP ≥ 2.5) |
BVD herd status |
|||
|---|---|---|---|---|
| |
(PP 2.12) |
(PP 7.58) |
||
| Negative | Positive | Negative | Positive | |
| Negative |
1 |
4 |
2 |
3 |
| Positive |
0 |
60 |
0 |
60 |
| % agreement in classification |
93.8% |
95.4% |
||
| (κ-value) | (0.32) | (0.55) | ||
The pooled serum results are separately presented at two different cut-off percentage positivity (PP) values (2.12 and 7.58). The level of agreement in BVD herd status, for non-vaccinated herds at each of the two cut-offs is presented, using kappa statistics.