Complete genome sequence of a non-pathogenic strain of Fowl Adenovirus serotype 11: Minimal genomic differences between pathogenic and non-pathogenic viruses

•Pathological characterization of FAdV-11 MX95 showed a low pathogenicity strain.•FAdV-11 MX95 is persistent in several organs of inoculated chickens.•Genome sequence of FAdV95 showed minimal genomic differences with high a pathogenicity strain.

In this study, we conducted the clinicopathological characterization of a non-pathogenic FAdV-D serotype 11 strain MX95, isolated from healthy chickens, and its entire genome was sequenced. Experiments in SPF chickens revealed that the strain is a non-pathogenic virus that did not cause death at challenge doses of 1×106 TCID50. Additionally, the infection in SPF chickens caused no apparent damage in most of the organs analyzed by necropsy and histopathology, but it did cause inclusion body hepatitis; nevertheless it did not generate severe infectious clinical symptoms. The virus was detected in several chicken organs, including the lymphoid organs, by real-time polymerase chain reaction (PCR) until 42 days. The genome of FAdV-11 MX95 has a size of 44,326 bp, and it encodes 36 open reading frames (ORFs). Comparative analysis of the genome indicated only 0.8% dissimilarity with a highly virulent serotype 11 that was previously reported.

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