Abstract: shan University, Foshan 528231, China）〖WT〗〖JZ)〗〖HJ1*2〗〖HJ〗
〖WT5”HZ〗Abstract: 〖WTBZ〗 Using the genome RNA of NDV-SS strain of Newcastle disease virus (NDV) isolated from duck as a template, the F gene of NDV-SS strain was amplified by reverse transcription polymerase chain reaction (RT-PCR). Then its gene cloning was completed, and its nucleotide sequence was determined. Nucleotide sequence homology and evolutionary processes analyses on amino acids sequence of F gene between SS strain and other NDV reference strains published in GenBank was executed using the sequence analysis soft. The F gene sequence of SS strain showed that NDV-SS strain was determined with its full-length of 1662 bp coding 553 amino acids. Amino acids sequence of F protein proteolytic cleavage position was 112R-R-Q-K-R-F117, indicated it is the virulent NDV strain．And the results of nucleotide sequence homology and evolutionary processes analyses showed that this strain belonged to the gene type Ⅵ, and had a close relationship with IT-227 and Italy-2736 strain. The presumable result was that this strain evolved from the NDV of pigeon origin.

Key words: Newcastle disease virus; ducks; F gene; cloning; sequence analysis