Isolation and identification of avian paramyxovirus serotype I from equine.

【Objective】This study was aimed to understand the biological characteristics of horse origin avian paramyxovirus serotype I and provide references for preventing and controlling the paramyxovirus interspecies transmission.【Method】 In Baise of Guangxi,causative agents were isolated from suspicious samples of horse using chicken embryos inoculation and cultured.After serological experiment and pathogenicity identification,F gene of isolates was amplified using RT-PCR and sequenced.【Result】The isolated strain could agglutinate chicken erythrocytes and was inhibited by Newcastle disease virus antiserum.Its titer of HA and HI was 27and 210,respectively.The MDT and ICPI of chicken embryos was 72 h and 1.48,respectively.The isolated strains,which was moderate susceptible,belonged to genotype Ⅶ,sharing 95.9% and 95.1% nucleotide sequence homologies with NDV04-21 and TW-96p,respectively.According to the phylogenetic tree of F gene,the isolates,NDV04-21 and TW-96p belonged to the same branch,which were APMV-I genotype Ⅶ.Amino acid sequence of the isolate fusion(F) protein cleavage site 112-117 was 3'-R-R-Q-K-R-F-5',which was in accordance with standard virulent strain HER33 and F48E9.【Conclusion】The results indicated that APMV-I infected horses.It was reconfirmed that hosts of APMW-1 were developing in Guangxi area.