Hydropericardium hepatitis syndrome (HHS) caused by fowl adenovirus-4 have been frequently reported in commercial chickens from several countries causing significant economical losses. In Azerbaijan, fowl adenovirus infections in broiler and layer breeders flocks cause severe disease and mortality. Here we investigated the pathological lesions and the dissemination of fowl adenovirus-4 into the visceral organs of infected birds. Tissue samples containing liver, heart and spleen from 20 necropsied chickens were collected on the FTA cards and presence of fowl adenovirus was analysed by PCR and sequencing.
Postmortem findings of both broiler and layer breeder chickens were similar, and the most affected organs were the liver with hepatitis and the heart with hydropericardium lesions. Other postmortem signs include swollen kidneys with haemorrhages and small white foci on the surface of the spleens. In some birds intestinal congestion and ecchymotic hemorrhages were also apparent.
The PCR analysis revealed that all collected organs from 20 birds showed presence of fowl adenovirus-4 genome. The sequence analysis showed that fowl adenovirus-4 prevalent in Azerbaijan carry more closer phylogenetic relationship with the viruses prevalent in the Middle East, Far East and Indian subcontinent. However, a distinct diversity was seen from the strains prevalent in Europe, North and South America. This study will provide evidence the impact of fowl adenovirus-4 on the poultry production and improved preventive disease control strategies are required to reduce the HHS disease in chickens in Azerbaijan.