Table III.
Description of scores of histological lesions during the first 10 days of vaccine trial after challenge with different IBV field isolates and frequency of birds that were classified as diseased on the basis of any histological lesions, or lesions that were medium or severe
| Isolate | Challenged (N) | Mean | Standard deviation | Diseaseda (Any; N) | Diseased (medium and severe; N) |
|---|---|---|---|---|---|
| IBV-ON1 | 15 | 2.47 | 1.06 | 11 | 9 |
| IBV-ON1-Vb | 15 | 1.67 | 0.82 | 7 | 3 |
| IBV-ON4 | 15 | 1.33 | 0.62 | 4 | 1 |
| IBV-ON4-V | 15 | 1.60 | 0.91 | 6 | 2 |
| IBV-ONM | 15 | 1.87 | 0.92 | 8 | 5 |
| IBV-ONM-V | 15 | 1.20 | 0.41 | 3 | 0 |
| NCc | 10 | 1.00 | 0.00 | 0 | 0 |
| NC-V | 10 | 1.00 | 0.00 | 0 | 0 |
a
The frequencies were used to calculate vaccine efficacy.
b
V = vaccinated.
c
Negative control.