An outbreak of duck hepatitis A virus infection in nomadic ducklings.

Abstract

During winter of the year 2020, a flock of 9 day‑old 5000 non‑descript ducklings was affected with huge daily mortality, dullness, depression and opisthotonus. Clinically, there was severe depression, spasmodic paddling and opisthotonus. On post‑mortem, liver was enlarged and pale with patchy ecchymoses. Presence of perihepatitis and pericardititis during post‑mortem examination of one duckling might be attributed to secondary bacterial infection. Upon completion of disease episode, there was 80 percent mortality in eight days and only less than 20 percent weak ducklings survived. Liver homogenate which was subjected for molecular confirmation through one‑step reverse transcriptase polymerase chain reaction (RT‑PCR) using primers for RNA dependent RNA polymerase (3D) gene yielded positivity for duck hepatitis A virus (DHAV‑1). Histological observation of liver revealed hepatocyte degeneration and necrosis. It is clear that DHAV‑1 which is epornitic in nature causes a major devastating disease endangering duck farming.