Isolation and Molecular Identification of Duck Hepatitis A Virus in Sharkia Governorate

Thirty two flocks were examined to investigate the incrimination of DHAV in the nervous signs and massive mortalities recorded among ducklings during 2014-2016 in Sharkia Governorate. The examined birds aged (2-11 days) were suffering from nervous signs; ataxia followed by opisthotonos, kicking spasmodically then rapid death. Enlarged liver with marked petechial haemorrhages, enlarged spleen, nephritis and swelling of the kidneys were seen. Viral isolation in ECE revealed stunting, subcutaneous hemorrhages covering the body, necrotic areas and greenish discoloration of embryonic liver in 22 samples (68.75%). DHAV identification was succeeded by RT-PCR using RNA extracted from the livers of collected samples and specific primers based on 3D gene in all above positive samples. It could be concluded that RT-PCR could be carried out on hepatic tissues for rapid diagnosis of common DHAV. The subtyping of DHAV is useful for accurate diagnosis to avoid vaccination failure.