Pathological and molecular diagnosis of duck enteritis virus in Khaki Campbell ducks in a field outbreak

The present study was undertaken for prompt diagnosis of outbreak by molecular detection of virus correlating with the pathological findings or lesions. An outbreak of duck virus enteritis (DVE) was occurred in a flock (n=40) of khaki Campbell ducks in September 2011 at BudBud, Burdwan, West Bengal. All 22 ducks of grower age group died but there was no mortality in 18 adult layer ducks except mild diarrhoea. On random necropsy of five dead birds, gross lesions in various organs were recorded and tissue samples collected aseptically for PCR assay and virus isolation as well as for histopathology. Prominent gross lesions observed were necrotic foci on enlarged liver, diphtheritic ulceration in esophagus, atrophy of bursa and petechiae in various organs. Microscopically, degeneration and necrosis of hepatic parenchyma, necrosis, desquamation and ulceration of esophageal epithelium, Zenker's degeneration of cardiac muscles and lymphoid depletion in bursa were observed. The pathognomic microscopic finding in all cases was presence of eosinophilic inclusion bodies in the hepatocytes. Virus was isolated on embryonated duck eggs from a PCR-positive liver sample. It was concluded that field outbreaks of DVE could be confirmed by PCR and viral isolation after correlating with clinical signs and pathological changes.