Abstract: A strain of canine distemper virus (CDV) was isolated from the domestic dog in Shandong province, the virus was identified by cell pathological effect observation and RT-PCR. The results showed that typical pathological changes appeared on Vero cells inoculated with the treated pathological material. A 287 bp fragment of nucleoprotein(N) gene was amplified from RNA extraction of Vero cell culture inoculated with the virus. The N gene of isolate shared 95.5% to 96.9% nucleotide homology with that of vaccine stains(Onderstepoort and Snyder Hill),and 97.2% to 99.0% nucleotide homology identity with that of virulent strains (A75/17 and 2544/Han95) and field strains (XJ-4, ZJ7, 98-2646 and so on), the phylogenetic tree also suggested that the isolate had close relationship with field strains, it indicated that the isolate was a CDV field strain, which was named QD10.

Key words: canine distemper virus; isolation; nucleoprotein gene; sequence analysis