Bergfeld Jemma, Meers Joanne, Bingham John, Harper Jennifer, Payne Jean, Lowther Sue, Marsh Glenn, Tachedjian Mary, Middleton Deborah
1 CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia.
2 School of Veterinary Science, The University of Queensland, Brisbane, Australia.
Vet Pathol. 2017 Jul;54(4):649-660. doi: 10.1177/0300985817705173. Epub 2017 May 11.
Newcastle disease is an important disease of poultry caused by virulent strains of Newcastle disease virus (NDV). During the 1998 to 2002 outbreaks of Newcastle disease in Australia, it was observed that the mild clinical signs seen in some chickens infected with NDV did not correlate with the viruses' virulent fusion protein cleavage site motifs or standard pathogenicity indices. The pathogenicity of 2 Australian NDV isolates was evaluated in experimentally challenged chickens based on clinical evaluation, histopathology, immunohistochemistry, and molecular techniques. One of these virus isolates, Meredith/02, was shown to induce only very mild clinical signs with no mortalities in an experimental setting, in contrast to the velogenic Herts 33/56 and Texas GB isolates. This minimal pathogenicity was associated with decreased virus replication and antigen distribution in tissues. This demonstrates that the Australian Meredith/02 NDV, despite possessing a virulent fusion protein cleavage site, did not display a velogenic phenotype.
新城疫是由新城疫病毒（NDV）强毒株引起的一种重要的家禽疾病。在1998年至2002年澳大利亚新城疫疫情期间，观察到一些感染NDV的鸡所表现出的轻微临床症状与病毒的强毒融合蛋白裂解位点基序或标准致病性指数不相关。基于临床评估、组织病理学、免疫组织化学和分子技术，对2株澳大利亚NDV分离株在实验感染鸡中的致病性进行了评估。与速发型的赫茨33/56和得克萨斯GB分离株相比，其中一株病毒分离株，即梅雷迪思/02，在实验环境中仅引起非常轻微的临床症状，无死亡情况。这种最小致病性与组织中病毒复制和抗原分布减少有关。这表明澳大利亚的梅雷迪思/02 NDV尽管具有强毒融合蛋白裂解位点，但并未表现出速发型表型。
