Molecular Characterization of Hydropericardium Hepatitis Syndrome in Broiler Chickens

Abstract

Infection with fowl adenoviruses (FAdVs) can lead to a number of syndromes inchickens. These syndromes, which include inclusion body hepatitis (IBH) and hepatitishydropericardium syndrome (HHS), as well as others, are responsible for tremendouseconomic losses all over the world. FAdVs can be broken down into a total of 12 differentserotypes and 5 different species (A–E; 1–8a and 8b–11). As a result of the extensivedistribution of FAdV strains, the vast majority of bird species are susceptible to infection.IBH and HHS are both caused by viruses belonging to the genus aviadenovirus, which is afamily within the adenoviridae viral family. In our study samples from IBH and HHSsuspected outbreaks were collected from Alexandria, Mars Matroh and Beheragovernorates. The affected broilers showed enlarged liver and kidney, straw-colored fluidaccumulates in the pericardial sac around the heart. The FAdVs infection confirmed byconventional PCR infection using Hexon gene specific primers then sequencing of 3selected FAdv the isolates. Phylogentic analysis of the obtained sequences in comparingwith reference strains from gene bank; the three isolates were highly similar to thecirculating FAdV type D in Egypt with nucleotide identity ranged 99 -100% and amino acididentity ranged 97.2-100%. While they are of low similarity with the other FAdV serotypeslocated in group D FAdV. Interestingly we found that FAdV species D was predominant inEgypt now specially FAdVs- 2/11.