Table 2 The histopathological scoring of trachea of chicken examined in all four groups

Epithelial injuery

8 birds^a

3^b

4 birds^a

2^b

3 birds^a

1^b

2 birds^a

2^b

Submucosal inflammation

13 birds^a

2^b

10 birds^a

1^b

8 birds^a

2^b

11 birds^a

3^b

Submucosal oedema

8 birds^a

2^b

7 birds^s

1^b

8 birds^z

1^b

13 birds^s

++^b

Submucosal haemorrhage

6 birds^a

1^b

2 birds^a

1^b

0 bird^a

0^b

5 birds^a

2^b