TABLE 6.
Group and protein | No. of chickens | No. of chickens with the following lesion scores:
|
Mean no. of chickens | |||||
---|---|---|---|---|---|---|---|---|
0 | 1+ | 2+ | 3+ | 4+ | 5+ | |||
Chickens infected with mild-moderate challenge | ||||||||
Vehicle-only controls | 10 | 0 | 5 | 2 | 0 | 1 | 2 | 2.3 |
FBAa | 13 | 4 | 6 | 1 | 1 | 0 | 1 | 1.23 |
Chickens infected with severe challenge | ||||||||
Vehicle-only controls | 11 | 0 | 3 | 2 | 3 | 1 | 2 | 2.72 |
Alpha-toxinb | 10 | 0 | 2 | 4 | 4 | 0 | 0 | 2.2 |
FBA | 14 | 1 | 4 | 9 | 0 | 0 | 0 | 1.57 |
The immunized group had significantly fewer chickens with lesions than the unimmunized vehicle-only control group (Fisher's exact test, P ≤ 0.05).
The birds in this group received three injections of alpha-toxin, in which the first and the third injections were with 20 μg and the second was reduced to 10 μg.