Table 1.
Histopathological findings in the lungs from control animals and cases of CBP
| Control |
CBP∗ |
|||||||
|---|---|---|---|---|---|---|---|---|
| (n = 60) |
Acute (n = 10) |
Subacute (n = 24) |
Chronic (n = 114) |
|||||
| n | % | n | % | n | % | n | % | |
| Bronchitis | 1 | 2 | 3 | 30 | 3 | 12 | 14 | 12 |
| Bronchiolitis | 1 | 2 | 6 | 60 | 8 | 33 | 30 | 26 |
| Bronchiolar polyps | 0 | – | 0 | – | 2 | 8 | 21 | 18 |
| BALT hyperplasia† | ||||||||
| 0 | 41 | 68 | 4 | 40 | 2 | 8 | 14 | 12 |
| + | 15 | 25 | 6 | 60 | 4 | 17 | 26 | 23 |
| ++ | 4 | 7 | 0 | – | 16 | 67 | 52 | 46 |
| +++ | 0 | – | 0 | – | 0 | – | 12 | 11 |
| ++++ | 0 | – | 0 | – | 2 | 8 | 10 | 9 |
| Alveolar oedema | 1 | 2 | 8 | 80 | 18 | 75 | 67 | 59 |
| Fibrin exudation into alveoli | 0 | – | 5 | 50 | 7 | 29 | 10 | 9 |
| Type II pneumocyte hyperplasia | 3 | 5 | 3 | 30 | 7 | 29 | 40 | 35 |
| Thickening of alveolar septa | 16 | 27 | 1 | 10 | 8 | 33 | 28 | 25 |
| Alveolar polyp-like structures | 0 | – | 2 | 20 | 9 | 38 | 30 | 26 |
| Smooth-muscle hyperplasia | 2 | 3 | 1 | 10 | 3 | 13 | 31 | 27 |
| Interstitial oedema | 2 | 3 | 7 | 70 | 10 | 42 | 34 | 30 |
| Interstitial fibroplasia | 2 | 3 | 1 | 10 | 5 | 21 | 34 | 30 |
| Necrotic foci | 0 | – | 0 | – | 1 | 4 | 8 | 7 |
∗
Cases of CBP were grouped as acute, subacute or chronic based on histological evaluation.
†
Hyperplasia of the BALT was scored as absent (0), mild (+), moderate (++), marked (+++) or extensive (++++).