Identification, pathogenicity and molecular characterization of a novel fowl adenovirus 8b strain

Yapeng Song; Lin Liu; Wenjie Sun; Wenming Gao; Xiaonan Song; Yang Wang; Qiang Wei; Zongmei Huang; Xinsheng Li

doi:10.1016/j.psj.2024.103725

Identification, pathogenicity and molecular characterization of a novel fowl adenovirus 8b strain

Poult Sci. 2024 Apr 3;103(6):103725. doi: 10.1016/j.psj.2024.103725. Online ahead of print.

Authors

Yapeng Song¹, Lin Liu¹, Wenjie Sun¹, Wenming Gao¹, Xiaonan Song¹, Yang Wang¹, Qiang Wei², Zongmei Huang¹, Xinsheng Li³

Affiliations

¹ College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China.
² Henan Provincial Key Laboratory of Animal Immunology, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, China.
³ College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, China. Electronic address: lxsh@henau.edu.cn.

Abstract

Since 2012, there has been a noticeable upward trend in the global incidence of inclusion body hepatitis (IBH) cases, leading to substantial economic losses in the poultry industry. In response to this trend, the current study aimed to investigate the phylogenetic information, genetic mutations, and pathogenicity of the highly pathogenic fowl adenovirus (FAdV) strain HN1472, which was isolated from liver samples obtained from a laying flock affected by IBH. This investigation was carried out using 1-day-old specific pathogen-free (SPF) chickens. Recombination and phylogenetic analyses confirmed that HN1472 is a recombinant strain derived from FAdV-8a and FAdV-8b, and exhibited significant genetic divergence in the hexon, fiber, and ORF19 genes. Notably, the phylogenetic analysis identified recombination events in these regions. Furthermore, animal experiments revealed that HN1472 is a highly pathogenic isolate, causing 80% mortality and manifesting clinical signs of IBH in SPF chickens. Furthermore, the recombinant FAdV serotype 8b (FAdV-8b) was found to be widely distributed in various tissues, with a higher concentration in the livers and gizzard tissue at 3 d postchallenge (dpc). Collectively, these findings contribute to our current understanding of the factors influencing the pathogenicity and genetic diversity of FAdV serotype 8b (FAdV-8b) in China.

Keywords: fowl adenovirus; identification; isolation; pathogenicity; recombination.