中文摘要：

从被感染猫体内分离出流感病毒，利用RT—PCR扩增NP基因，分析其遗传变异性。与NCBI上的14株流感病毒的NP全基因序列进行比对分析，发现其与参考毒株的NP基因序列的相似性为79．3％-99．7％，其中与感染株A／canine／Guangdong／1／2007（H3N2）的NP基因序列的相似性最高，为99．7％。基因序列比对发现，编码区存在5处突变：A33G、A81G、C235T、G345A、A567G：氨基酸仅存在1处变异：1189M。研究结果表明，犬流感病毒在犬和猫之间存在跨中间传播，虽然变异系数不高，但是567位碱基突变所造成的氨基酸突变为NP基因的遗传性和种间特异性的研究提供了参考。

英文摘要：

The study mainly discussed the genetic variation of NP gene of H3N2 subtype feline influenza virus after infection of canine-origin influenza virus. The feline was artificially infected with H3N2 subtypes canine influenza virus. The full length of NP gene was compared with the other 14 different types of influenza viruses in the Genbank datebase. The results revealed that similarity between each other was ranging from 79.3% to 99.7%. The nueleotide identity between infection and inoculation A/canine/Guangdong/1/2007 （H3N2） was the highest （99.7%）. After the comparison of gene sequence, five mutations were found in the coding region （A33G, A81G, C235T, G345A, A567G）. However, only one amino acid mutations was found （I189M）. The results showed that canine influenza virus can spread across species, although the variation of NP gene was not significant, but the amino acids mutations caused by the 567 base provide reference statistics for the study of heredity and Species-specific of NP gene.