Table 1.
Range of F gene nucleotide sequence similarity (%) of NDV strains within one genotype and between different genotypes
| Genotype (No. of sequences) |
I | II | III | IV | V | VI | VII | VIII | IX |
|---|---|---|---|---|---|---|---|---|---|
| I(23) | >91.8 | 87.0-91.8 | 88.6-93.3 | 86.2-92.5 | 81.9-86.3 | 83.4-87.9 | 82.6-92.2 | 85.8-89.7 | 89.3-91.7 |
| II(32) | - | >89.1 | 87.1-91.2 | 85.1-90.0 | 81.2-85.3 | 82.3-86.4 | 80.9-90.1 | 84.8-88.0 | 88.5-89.9 |
| III(6) | - | - | >92.4 | 87.8-94.6 | 83.5-88.3 | 83.7-90.1 | 83.2-89.1 | 87.1-91.6 | 91.2-94.3 |
| IV(5) | - | - | - | >92.2 | 83.6-89.5 | 84.8-91.3 | 84.1-89.6 | 86.7-92.2 | 88.6-92.9 |
| V(11) | - | - | - | - | >89.2 | 84.4-90.9 | 82.7-88.5 | 86.7-90.8 | 84.4-87.4 |
| VI(16) | - | - | - | - | - | >91.4 | 84.8-92.4 | 88.4-92.4 | 84.8-88.7 |
| VII(45) | - | - | - | - | - | - | >84.6 | 86.3-91.2 | 84.8-87.7 |
| VIII(2) | - | - | - | - | - | - | - | >93.1 | 87.6-90.1 |
| IX(7) | - | - | - | - | - | - | - | - | >99.3 |
The nucleotide sequence similarity of NDV strains were calculated by the MegAlign program in the Lasergene package (DNASTAR Inc. Madison, WI 53715, USA). 30 sequences of full-length genome together with more than one hundred sequences of complete F gene were involved.