Table 2.
Survival, body temperatures, body weights and HI titers of ducks inoculated with vNDV, LPAIV and HPAIV, given single or combined.
| Groups | Day of inoculationa
|
# dead/ total (MDT)b | Body temperaturec 2 dpi | Body weightsc 2 dpi | HI titersd
|
||
|---|---|---|---|---|---|---|---|
| Day 0 | Day 2 | NDV | AIV | ||||
| 1 | - | - | 0/9 | 107.0±0.6A | 694±55AB | ND | ND |
| 2 | vNDV | - | 0/9 | 107.5±0.5A | 638±81AB | 7/7 (5.7+.9) | ND |
| 3 | LPAIV | - | 0/9 | 107.7±0.8A | 705±12A | ND | 7/7 (3.8+.3) |
| 4 | HPAIV | - | 9/9 (2.3)AB | 103.6±4.3B | 576±27B | ND | ND |
| 5 | vNDV +LPAIV | - | 0/9 | 107.6±0.5A | 682±49AB | 7/7 (5.8+.6) | 6/7 (3) |
| 6 | vNDV +HPAIV | - | 9/9 (2.1)A | 107.9±2.6A | 672±73AB | ND | ND |
| 7 | vNDV | LPAIV | 0/9 | 108.0±0.8A | 838±79A | 7/7 (5.2+.7) | 0/7 |
| 8 | vNDV | HPAIV | 9/9 (3.2)B | 109.5±0.8B | 748±113A | ND | ND |
| 9 | LPAIV | vNDV | 0/9 | 107.6±0.8A | 867±130A | 7/7 (5.5+.5) | 4/7 (3.2+.5) |
| 10 | HPAIV | vNDV | 9/9 (2.3)AB | ND | - | ND | ND |
Two-week-old Pekin ducks were inoculated with 107 EID50 of vNDV, 107.5 EID50 of LPAIV, and 106 EID50 of HPAIV administered in 0.1 ml split between the right eye and the choana. The viruses were given alone, simultaneously, or sequentially (the second virus 2 days after the first).
Mean death time calculated after exposure to the HPAIV. Survival in groups with different uppercase letters is significantly different (P<0.05).
Body temperature (F) and weights in groups with different uppercase letters are significantly different (P<0.05).
Mean HI titers (log2) in ducks. Serum samples were taken at 8 or 10 days after infection with LPAIV, vNDV, or both. The number of birds with positive HI titers is shown. ≥ threshold of positivity/total number of sera tested (mean ± SEM).
ND = no data