Pathogenicity of Fowl Aviadenovirus serotype 11 in Specific Pathogen Free Chicken Embryos

Abstract

Inclusion body hepatitis (IBH) associated with fowl aviadenovirus (FAdV) infection has a world-wide distribution, especially for broilers aged 3 to 5 weeks, causing significant economic losses to poultry industry. In present study, we evaluated the pathogenicity of Moroccan FAdV serotype 11 (MOR111115 strain) in specific pathogen free (SPF) white leghorn chicken embryos. FAdV (titre 10?/ml) was inoculated to SPF embryonated chicken eggs through the chorioallontoic membrane (CAM). The mortality, gross and microscopical lesions of the embryos were evaluated and the presence of the virus was checked by PCR. 100% cumulative embryonic mortality was observed at 7 days post-infection (dpi). The inoculated embryos were hemorragic and the liver was friable and swollen, with yellow to greenish discoloration. Microscopically, we highlighted a multifocal necrosis of hepatocytes groups with the presence of basophilic and eosinophilic intra-nuclear inclusion bodies within hepatocytes. The presence of the virus was confirmed by conventional polymerase chain reaction based on hexon gene from liver.that is a major target organ of FAdV infections. This is the first study of pathogenicity of fowl aviadenovirus in SPF chicken embryos in Morocco. Keywords: Fowl aviadenovirus-11, Inclusion body hepatitis, Pathogenicity, Chicken embryos