Table 3.
Gross lesions in SPF chickens infected with QX-like IBV strain SD at different ages.
| Group | Lesions | Days post inoculation (dpi) | ||||
|---|---|---|---|---|---|---|
| 5 | 7 | 9 | 14 | Xa | ||
| 1 | Tracheal exudate/hemorrhage | 0/2b | 2/2 | 2/2 | 0/2 | – |
| Laryngeal exudate/hemorrhage | 2/2 | 2/2 | 0/2 | 0/2 | – | |
| Renal enlargement/urate | 1/2 | 2/2 | 1/2 | 2/2 | – | |
| Abnormal follicular development | – | – | – | – | 6/18 | |
| Abnormal development of oviduct | – | – | – | – | 9/18 | |
| 2 | Tracheal exudate/hemorrhage | 0/2 | 1/2 | 1/2 | 2/2 | – |
| Laryngeal exudate/hemorrhage | 0/2 | 0/2 | 0/2 | 2/2 | – | |
| Renal enlargement/urate | 2/2 | 1/2 | 1/2 | 2/2 | – | |
| Abnormal follicular development | – | – | – | – | 8/20 | |
| Abnormal development of oviduct | – | – | – | – | 3/20 | |
| 3 | Tracheal exudate/hemorrhage | 2/2 | 2/2 | 1/2 | 2/2 | – |
| Laryngeal exudate/hemorrhage | 1/2 | 0/2 | 2/2 | 2/2 | – | |
| Renal enlargement/urate | 0/2 | 2/2 | 2/2 | 2/2 | – | |
| Abnormal follicular development | – | – | – | – | 1/11 | |
| Abnormal development of oviduct | – | – | – | – | 1/11 | |
| 4 | Tracheal exudate/hemorrhage | 2/2 | 1/2 | 2/2 | 2/2 | – |
| Laryngeal exudate/hemorrhage | 1/2 | 1/2 | 0/2 | 0/2 | – | |
| Renal enlargement/urate | 1/2 | 0/2 | 1/2 | 2/2 | – | |
| Abnormal follicular development | – | – | – | – | 2/7 | |
| Abnormal development of oviduct | – | – | – | – | 1/7 | |
| 5 | Tracheal exudate/hemorrhage | 2/2 | 2/2 | 0/2 | – | – |
| Laryngeal exudate/hemorrhage | 0/2 | 0/2 | 0/2 | – | – | |
| Renal enlargement/urate | 1/2 | 2/2 | 2/2 | – | – | |
| Abnormal follicular development | – | – | – | – | 3/9 | |
| Abnormal development of oviduct | – | – | – | – | 1/9 | |
| 6 | Tracheal exudate/hemorrhage | 0/10 | 0/10 | 0/10 | 0/8 | – |
| Laryngeal exudate/hemorrhage | 0/10 | 0/10 | 0/10 | 0/8 | – | |
| Renal enlargement/urate | 0/10 | 0/10 | 0/10 | 0/8 | – | |
| Abnormal follicular development | – | – | – | – | 0/12 | |
| Abnormal development of oviduct | – | – | – | – | 0/12 | |
Group 1, 2-weeks-old chickens infected with IBV strain SD. Group 2, 3-weeks-old chickens infected with IBV strain SD. Group 3, 8-weeks-old chickens infected with IBV strain SD. Group 4, 18-weeks-old chickens infected with IBV strain SD. Group 5, 22-weeks-old chickens infected with IBV strain SD. Group 6, control group.
aEnd of observation period at 168 d.
bNumber of chickens exhibiting gross lesions out of the examined number of birds.