Asia-Pacific Centre for Animal Health, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, 3010, Australia.
Asia-Pacific Centre for Animal Health, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Victoria, 3030, Australia.
Vet Microbiol. 2020 Apr;243:108635. doi: 10.1016/j.vetmic.2020.108635. Epub 2020 Mar 4.
Infectious laryngotracheitis virus (ILTV) is an economically significant respiratory pathogen of poultry. Novel recombinant strains of ILTV have emerged in Australia during the last decade and currently class 9 (CL9) and class 10 (CL10) ILTV are the most prevalent circulating strains. This study conducted a comprehensive investigation of the pathogenesis of these two viral strains. Commercial broiler and specific pathogen free (SPF) chickens were inoculated with varying doses of CL9 or CL10 ILTV and subsequently evaluated for clinical and pathological signs of infection. While no difference in the levels of acute viral replication were observed across the different challenge doses, the severity of clinical signs, tracheal pathology and mortality were dose dependent. Both strains of virus persisted in the respiratory tract for up to 14 days post inoculation (dpi) and could be detected in the lung and feathers with sporadic detection in the liver, spleen or bursa. Given the prevalence of CL9 and CL10 in Australian poultry flocks, this study provides an important foundation for the development of diagnostic and therapeutic approaches for the detection and prevention of ILTV.
传染性喉气管炎病毒（ILTV）是一种对禽类具有重要经济意义的呼吸道病原体。在过去十年中，澳大利亚出现了新型重组 ILTV 株，目前，9 类（CL9）和 10 类（CL10）ILTV 是最流行的循环株。本研究对这两种病毒株的发病机制进行了全面调查。商用肉鸡和无特定病原体（SPF）鸡用不同剂量的 CL9 或 CL10 ILTV 接种，并随后评估感染的临床和病理迹象。虽然在不同的挑战剂量下，急性病毒复制水平没有差异，但临床症状、气管病理和死亡率的严重程度与剂量有关。两种病毒株在接种后长达 14 天（dpi）仍存在于呼吸道中，并可在肺部和羽毛中检测到，偶尔也可在肝脏、脾脏或法氏囊中检测到。鉴于 CL9 和 CL10 在澳大利亚家禽群中的流行，本研究为开发用于检测和预防 ILTV 的诊断和治疗方法提供了重要基础。
