Development of nested polymerase chain reaction-based diagnosis of duck enteritis virus and detection of DNA polymerase gene from non-descriptive duck breeds of West Bengal, India

AIM: The study was undertaken to detect the clinical signs, postmortem lesions of embryonated duck plague (DP) infected eggs, and histopathological changes of chorioallantoic membrane (CAM) in non-descriptive ducks of West Bengal with special reference to standardize nested polymerase chain reaction (PCR). MATERIALS AND METHODS: After postmortem of suspected carcasses, samples were collected for virus isolation and identification through specific pathogen free (Khaki Campbell) embryonated duck eggs. PCR was also done as confirmatory test after doing postmortem of duck embryos. DP specific nested PCR was standardized for better confirmation of the disease. Sensitivity of nested primers was also tested for DP virus. RESULTS: Gross, postmortem and histopathological changes were prominent in dead embryos. First set of primer was able to detect 602 bp fragments of DNA polymerase gene of duck enteritis virus from infected CAM. Subsequently, a DP specific nested PCR which was very much sensitive for very small amount of viral genome was successfully standardized. After NCBI blast nucleotide sequence of nested PCR product (Accession No. HG425076) showed homology with the sequences data available in GenBank. CONCLUSION: The study concludes that PCR assay is very much helpful to diagnose DP disease and developed nested PCR is a double confirmatory diagnostic tool for DP.