State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin 150001, China.
Department of Pathology, University of Agriculture, Faisalabad 38040, Pakistan.
Vet Microbiol. 2020 May;244:108670. doi: 10.1016/j.vetmic.2020.108670. Epub 2020 Apr 14.
Inclusion body hepatitis (IBH), hydropericardium syndrome, and gizzard erosion associated with fowl adenovirus (FAdV) infections are reported globally and resulted in significant poultry industry economic losses. In 2018, severe IBH appeared in Pakistan in a 17-week-old layer flock. Subsequently, a FAdV-11 strain (designated as PKFAd18) was isolated from liver samples and identified based on phylogenetic analyses of the serotype-specific L1 region of the capsid hexon gene. There is no complete genome sequence of the Pakistani FAdV-11. This study successfully sequenced the complete genome of PKFAd18. The full genome of PKFAd18 contains 43 840 base pairs (bp) with a G + C content of 53.9 %, which is comparable to other FAdV serotypes. Similar to other FAdV-11 strains, PKFAd18 has only one fiber, while FAdV-1 and FAdV-4 have two fibers. Notably, PKFAd18 showed unique characteristics compared to other FAdV-11 strains. A natural large genomic deletion (1215 bp) appeared in tandem repeat region two, relative to the ON-NP2 strain. Phylogenetic analyses of the PKFAd18 penton gene showed higher homology with FAdV-9, highlighting potential natural recombination between FAdV-11 and FAdV-9. Moreover, the pathogenicity of PKFAd18 studied in specific-pathogen-free chickens showed that PKFAd18 is capable of inducing severe IBH and could be responsible for IBH in Pakistan. Thus, the first complete genome of FAdV-11 in Pakistan was sequenced in this study, which enriches the diversity of knowledge about FAdV-11 and is useful for developing diagnostics and vaccines for IBH induced by FAdV-11 in Pakistan.
包涵体肝炎（IBH）、心包积水综合征和肌胃糜烂与禽腺病毒（FAdV）感染有关，在全球范围内都有报道，并导致家禽业遭受重大经济损失。2018 年，巴基斯坦一个 17 周龄的蛋鸡群中出现了严重的 IBH。随后，从肝脏样本中分离到一株 FAdV-11 毒株（命名为 PKFAd18），并根据衣壳六邻体基因的血清型特异性 L1 区的系统进化分析进行了鉴定。目前还没有巴基斯坦 FAdV-11 的完整基因组序列。本研究成功测序了 PKFAd18 的完整基因组。PKFAd18 的全基因组包含 43840 个碱基对（bp），G+C 含量为 53.9%，与其他 FAdV 血清型相当。与其他 FAdV-11 株一样，PKFAd18 只有一个纤维蛋白，而 FAdV-1 和 FAdV-4 有两个纤维蛋白。值得注意的是，PKFAd18 与其他 FAdV-11 株相比具有独特的特征。与 ON-NP2 株相比，在串联重复区 2 中出现了一个天然的大基因组缺失（1215bp）。PKFAd18 五邻体基因的系统进化分析显示与 FAdV-9 具有更高的同源性，这表明 FAdV-11 和 FAdV-9 之间可能存在自然重组。此外，在无特定病原体鸡中研究 PKFAd18 的致病性表明，PKFAd18 能够诱导严重的 IBH，可能是巴基斯坦 IBH 的罪魁祸首。因此，本研究首次对巴基斯坦的 FAdV-11 进行了全基因组测序，丰富了对 FAdV-11 的多样性认识，有助于开发针对巴基斯坦由 FAdV-11 引起的 IBH 的诊断和疫苗。
