Pathological effects of avian influenza virus antigens (H9N2 subgroup) using a chicken embryo model

Document Type : Original Article

Authors
Shirin Mohammadipour 1
Hadi Tavakoli
Aram Sharifi 2
Sepideh Asadi 3
Mojtaba Khosravi 4
1 Department of Pathobiology, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman- Iran.
2 Department of Animal Science, Faculty of Agriculture, University of Kurdistan, Sanandaj, Kurdistan- Iran.
3 Department of Pathobiology, Faculty of Veterinary Medicine, Amol University of Special Modern Technologies, Amol- Iran
4 Department of Pathobiology, Faculty of Veterinary Medicine, Amol University of Special Modern Technologies, Amol- Iran.
10.22034/ijvcs.2025.15134.1131
Abstract
The H9N2 subtype of influenza virus is prevalent not only across various regions in Iran but also poses a zoonotic risk, capable of transmission from birds to humans. This makes it a potential candidate for future pandemic outbreaks. The present study was aimed to investigated the pathological effects of avian influenza virus antigens (H9N2 subgroup) on the chicken embryo. Accordingly, the antigenic extracts of the H9N2 virus at a dose of 106 EID50/ml were injected into commercial fertilized eggs to assess the pathological effects on developing embryos. The findings indicated significant adverse impacts on embryonic weight and growth throughout development, notably reducing parameters associated with embryonic mass and growth rates (P<0.05). Severe pathological effects were observed in the brain and liver tissues of the embryos. This study suggests that the indigenous H9N2 subtype in Iran can cause extensive pathological impacts on developing embryos. Further studies are needed to investigate the molecular and cellular mechanisms through which the H9N2 influenza antigen affects embryonic development.
Keywords
Influenza
Commercial poultry
Zoonosis
H9N2
Subjects
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Iranian Journal of Veterinary Clinical Sciences
Volume 19, Issue 1 - Serial Number 32
Spring & Summer 2025
August 2025
Pages 59-65