Abstract：
Avibacterium paragallinarum (A. paragallinarum) is the aetiological agent of infectious coryza (IC) in chickens and characterized by acute respiratory distress and severe drop in egg production. Vaccination is important in the control of IC outbreaks and the efficacy of vaccination is dependent on A. paragallinarum serovars included in the vaccine. Classical serotyping of A. paragallinarum is laborious and hampered by poor availability of antigens and antisera. The haemagglutinin, important in classical serotyping, is encoded by the HMTp210 gene. HMTp210 gene analysis has been shown to have potential as alternative to classical serotyping. The aim of the present study was to further investigate the potential of sequence analyses of partial region 1 of the HMTp210 gene, the HMTp210 hypervariable region and the concatenated sequences of both fragments. For this analysis, 123 HMTp210 gene sequences (field isolates, A. paragallinarum serovar reference strains and vaccine strains) were included. Evaluation of serovar references and vaccine strains revealed a need for critical evaluation, especially within Page serovar B and C. Phylogenetic analysis of HMTp210 region 1 resulted in a separation of Page serovar A, B and C strains. Analysis of the HMTp210 HVR alone was not sufficient to discriminate all nine different Kume serovar references. The concatenated sequences of HMTp210 region 1 and HMTp210 HVR resulted in 14 clusters with a high correlation with Page serovar and with the nine currently known Kume serovars and is therefore proposed as a novel genotyping method that could be used as an alternative for classical serotyping of A. paragallinarum.
摘要：
副杆菌（A.paragallinarum）是鸡中传染性鼻炎（IC）的病原体，其特征是急性呼吸窘迫和产蛋量严重下降。疫苗接种在IC爆发的控制中是重要的,并且疫苗接种的效力取决于包括在疫苗中的副鸡副乳杆菌血清变型。对副鸡根霉的经典血清分型是费力的,并且由于抗原和抗血清的低可用性而受到阻碍。血凝素（HA），在经典血清分型中重要的是由HMTp210基因编码。HMTp210基因分析已显示具有替代经典血清分型的潜力。本研究的目的是进一步研究HMTp210基因之一的1~1200核苷酸序列分析的潜力，HMTp210高变区和两个基因片段的串联序列。对于此分析123HMTp210基因序列(田间分离株，包括副鸡曲霉血清变型参考菌株和疫苗菌株)。血清变型参考文献和疫苗株的评估表明需要进行严格的评估，特别是在Page血清型B和C中。HMTp210区域1的系统发育分析导致Page血清型A分离，B和C菌株。仅对HMTp210HVR的分析不足以区分所有9种不同的Kume血清变型参考。HMTp210区域1和HMTp210HVR的串联序列导致14个簇，与Page血清型和目前已知的9个Kume血清型高度相关，因此被提议作为一种新的基因分型方法，可用作经典血清分型的替代方法。
