Table 4.
Correlation between levels of neutralizing antibody and protective efficacies conferred by TMUV PS180.
| Group† | ND50 titer | Mortality (%) | Mean body weight (g)§ |
|---|---|---|---|
| PS180-104/Y4 | 1,584–3,162 | 0 (0/10)‡ | 572 ± 20 |
| PS180-103/Y4 | 1,258–2,511 | 0 (0/10) | 560 ± 30 |
| PS180-102/Y4 | 631–1,548 | 10 (1/10) | 450 ± 26* |
| PS180-10/Y4 | 251–398 | 40 (4/10) | 414 ± 50* |
| Mock/Y4 | 25–158 | 50 (5/10) | 400 ± 39* |
| Control | 32–126 | 0 (0/10) | 580 ± 18 |
†
Pekin ducks were inoculated with 104 to 10 PFU of PS180 and DMEM at 1 day of age. Ducks in five groups were challenged with 105 PFU of TMUV Y4 at 7 days of age. Serum was sampled from 7-days-old ducks before challenge.
‡
No. of death/no. of ducks challenged.
§
The ducks were weighed at 7 days after challenge.
*
Significant difference compared with control (P < 0.05).