Table 2.
The mortality and protection rate of different groups challenged by virulent IBV SAIBk strain.
| Groups | No. of death | No. of affecteda | Mortalityb (%) | Protection ratec (%) |
|---|---|---|---|---|
| pVAX-F | 1 | 3 | 6.67 | 80.00 |
| Inactivated vaccine | 2 | 4 | 13.33 | 73.33 |
| pVAX1 | 6 | 15 | 40.00 | 0 |
| PBS | 7 | 15 | 46.67 | 0 |
a
Affected was determined by RT-PCR positive birds from dead and euthanized chickens′ kidneys.
b
Mortality was recorded for each day after challenge and is presented as total number of dead chickens in each group.
c
Percent of protection was determined by the number of unaffected chickens/total number of chickens in each group. It was showed that 12 out 15 chickens in the multi-epitope DNA vaccine immunized group didn′t affect IBV, and 11 out of 15 chickens in was protected in inactive vaccine group, while all the chickens in pVAX1 group and PBS group were affected IBV.