Virus | Passage history* | Titer (pfu/mL) | Plaque size # (mm) | MLD50‡ | Survival time (i.n.) †| survival time (i.v.) †|
|---|
VN1194-W | Egg × 2 | 4.2×108 | 0.096±0.038 | 0.66 | 8.1±0.43 | 5.6±0.40 |
VN1194-P | Egg × 4; MDCK ×3 | 4.88×106 | Mixed ND§ | 1.54×103 | 14 | 13.4±0.57 |
1194-SP | MDCK ×1 | 1.67×106 | 0.080±0.026 | 52.87 | 7.6±0.71 | ND§ |
1194-LP | MDCK ×1 | 6.50×106 | 0.746±0.225 | 6.50×104 | 14 | 14 |
1194-ML | MDCK ×1 | 1.85×106 | Mixed, ND§ | 3.95×102 | 13.3±0.66 | ND§ |
1194-MB | MDCK ×1 | 4.40×107 | 0.079±0.034 | 87.6 | 10.8±1.00 | ND§ |
- * Prepared in chicken embryos or MDCK cells for 48-60 hours.
- # Average plaque size(mm, means ± SEs)
- ‡ Expressed as the pfu to give 1 LD50.
- †Average survival time (days) (means ± SEs of 10 mice per group) after intranasal or intravenous infection.
- Mean survival time was estimated by the Kaplan-Meier method. Fisher's exact test was used to analyze the differences in survival rates between groups when no censored observations presented. Significant differences were observed in mean survival time between VN1194-W group and VN1194-P group and between 1194-LP group and 1194-SP group (P < 0.01), No significant differences were observed between VN1194-W group and 1194-SP group (P > 0.05). Significant differences were observed between VN1194-W group and 1194-MB group (P < 0.05), but no significant differences between 1194-ML group and VN1194-P group (P > 0.05)
- § ND: not determined.
