الفهرس | Only 14 pages are availabe for public view |
Abstract Fowl aviadenoviruses (FAdV) have gained increasing attention in Egypt and worldwide nowadays, as they are the primary etiology of many widespread diseases. Among these diseases, inclusion body hepatitis (IBH). Many outbreaks of IBH have been recorded in the last few years across the country, causing significant economic losses to the Egyptian poultry industry. The present study was undertaken to detect FAdVs from field outbreaks of IBH in broiler chickens in North Sinai province during the period from May 2016 till December 2017. Affected birds adopt a crouching position with ruffled feathers, depression, reduced feed intake, pale comb and facial skin. On necropsy, the most common postmortem lesions were hydropericardium, yellowish enlarged liver with II ecchymotic hemorrhages, pancreatitis, and enteritis. Histopathological examination of liver samples collected at different stages of infection showed multifocal necrosis, extensive congestion with inflammatory cellular infiltration. The presence of intranuclear inclusion bodies (INIB) was variable among samples. FAdV were detected in liver samples from eleven flocks out of the fourteen examined by real-time polymerase chain reaction (real-time PCR) using commercial kits with differences in viral load among samples. DNA samples from four flocks that exhibited the highest viral loads were further amplified in conventional PCR targeting hexon gene followed by sequencing of the specific PCR products. Phylogenetic analysis based on sequencing of the hexon loop-1 gene showed that the four isolates (Sin-1, Sin-2, Sin-3, and Sin-4) were clustered into serotype-2, FAdV-D species. The strains in this study are sharing 99.82%, 99.63%, 99.60, and 98.2% nucleotide identity with hexon loop-1 gene sequences of FADV-2 (species D) of Israel, Japan, Egypt, and Canada, respectively. This study provides epidemiological information that could be helpful in the formulation of an effective prevention strategy. |