College of Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai'an City, Shandong Province, 271018, China; Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, 61 Daizong Street, Tai'an City, Shandong Province, 271018, China; Shandong Provincial Engineering Technology Research Center of Animal Disease Control and Prevention, 61 Daizong Street, Tai'an City, Shandong Province, 271018, China.
China Animal Health and Epidemiology Center, 369 Nanjing Street, Qingdao, Shandong, 266000, China.
Vet Microbiol. 2018 May;218:52-59. doi: 10.1016/j.vetmic.2018.03.019. Epub 2018 Mar 17.
Inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) induced by fowl adenovirus type 4 (FAdV-4) has caused huge economic losses to the poultry industry of China, but the source of infection for different flocks, especially flocks with high biological safety conditions, has remained unclear. This study tested the pathogenicity of Newcastle disease virus (NDV)-attenuated vaccine from a large-scale poultry farm in China where IBH-HPS had appeared with high mortality. Analysis revealed that the NDV-attenuated vaccine in use from the abovementioned poultry farm was simultaneously contaminated with FAdV-4 and chicken infectious anemia virus (CIAV). The FAdV and CIAV isolated from the vaccine were purified for the artificial preparation of an NDV-attenuated vaccine singly contaminated with FAdV or CIAV, or simultaneously contaminated with both of them. Seven-day-old specific pathogen-free chicks were inoculated with the artificially prepared contaminated vaccines and tested for corresponding indices. The experiments showed that no hydropericardium syndrome (HPS) and corresponding death occurred after administering the NDV-attenuated vaccine singly contaminated with FAdV or CIAV, but a mortality of 75% with IBH-HPS was commonly found in birds after administering the NDV-attenuated vaccine co-contaminated with FAdV and CIAV. In conclusion, this study found the co-contamination of FAdV-4 and CIAV in the same attenuated vaccine and confirmed that such a contaminated attenuated vaccine was a significant source of infection for outbreaks of IBH-HPS in some flocks.
包涵体肝炎-心包积水综合征（IBH-HPS）由禽腺病毒 4 型（FAdV-4）引起，给中国家禽业造成了巨大的经济损失，但不同鸡群，尤其是生物安全条件较高的鸡群的感染源仍不清楚。本研究检测了在中国发生包涵体肝炎-心包积水综合征（IBH-HPS）高死亡率的大型家禽养殖场使用的新城疫病毒（NDV）减毒疫苗的致病性。分析表明，来自上述家禽养殖场的使用中的 NDV 减毒疫苗同时污染了禽腺病毒 4 型（FAdV-4）和鸡传染性贫血病毒（CIAV）。从疫苗中分离出的 FAdV 和 CIAV 经纯化后，人工制备了单独污染 FAdV 或 CIAV 的 NDV 减毒疫苗，或同时污染两者的 NDV 减毒疫苗。7 日龄 SPF 鸡接种人工制备的污染疫苗，并检测相应的指标。实验表明，单独污染 FAdV 或 CIAV 的 NDV 减毒疫苗接种后不会引起心包积水综合征（HPS）和相应的死亡，但同时污染 FAdV 和 CIAV 的 NDV 减毒疫苗接种后，鸡群普遍出现 75%的包涵体肝炎（IBH）-心包积水综合征（HPS）死亡率。综上所述，本研究发现 FAdV-4 和 CIAV 同时存在于同一减毒疫苗中，并证实这种污染的减毒疫苗是某些鸡群暴发包涵体肝炎-心包积水综合征（IBH-HPS）的重要感染源。
