Localization of duck hepatitis B virus in the liver

Localization of DHBV was investigated in the liver of ducks utilizing immunoperoxidase and electron microscopic methods. Inoculation of DHBV-positive sera within 24 hours after hatching resulted in persistent infection as demonstrated by DHBV-DNA and DNA polymerase activity in the sera. The immunostaining showed staining of DHBV in the cytoplasm of hepatocytes andbiliary epithelial cells. Ultrathin sections of the pellet of DHBV-positive sera showed two kinds of virus particles. One was 34 to 63nm in diameter and the other (probably virions, 40nm in diameter) had a markedly electron-dense core with and envelope. The DHBV-positive livers had many envelope-like and a few virion-like particles within the cisternae of endoplasmic reticula and a few core-like particles in the hyaloplasm of hepatocytes. The localization in the hepatocytes seems to be somewhat similar between DHBV and HBV.