不同基因型禽Ⅰ型副粘病毒致病性及全基因组序列分析

Pathogenicity and Genome Sequence Analysis of Different Genotype of Avian Paramyxovirus Type 1

为了解当前流行于鸭群的禽I型副粘病毒的致病性和分子特征,测定分析了两株病毒对不同动物的致病性、病毒的遗传进化地位及其全基因组序列。结果表明,所分离的两株病毒中,M4毒株与疫苗Ulster株同源性最高,为基因I型,基因组全长15 186nt,PX2/03毒株则与近来分离自水禽的FP1/02等高致病分离株的同源性最高,为基因VIII型,基因组全长15 192nt。尽管两株病毒间的基因组核苷酸同源性很高,为92.3%,但二者致病性差异明显,毒株M4感染SPF鸡和鸭均未引起明显发病症状,而PX2/03毒株对1日龄雏鸡、6周龄SPF鸡及不同品种的雏鸭都表现出高致病性。另外,动物感染试验表明,尽管PX2/03毒株对3种鸭的致死性差异不明显,番鸭较半番鸭及樱桃谷鸭对PX2/03毒株更易感。

To keep track of the pathogenicity and genomic features of avian paramyxovirus type 1 prevailing in ducks,virulence to different animals and genome sequences of two isolates as well as its genetic diversity and evolution were determined.Phylogenetic analysis showed that M4 shared a high identity with vaccine strain Ulster and belonged to genotype I,while PX2/03 isolate clustered with those virulent waterfowl isolates,such as FP1/02,which were belong to genotype VIII.Genome sequencing results showed that the genome size of M4 is 15186 bp,which is six bp shorter than that of PX2/03,and despite the fact that the two isolates shared a high identity of 92.3% with each other,they distinct significantly in pathogenicity.M4 strain was almost nonpathogenic while PX2/03 was highly pathogenic to chicken and different species of ducks.Additional,animal experiment results indicated that Muscovy duck was more susceptible to PX2/03 isolate than Mule duck or cherry valley duck does despite the similar fatality of these animals after infected with strain PX2/03.