[Ultrastructural study and localization of duck hepatitis B virus in the livers of experimentally infected ducks].

An electron microscopic study was performed to investigate the occurrence and localization of duck hepatitis B virus (DHBV) in the livers of infected Beijing ducks. DHBV-DNA was found in trace amounts in liver extract on 9th hours after infection by Southern blot hybridization and was found in serum on the 4th day of infection. Virus particles were recognized in the hepatocytes as early as the 3rd day of infection. Many incomplete virus particles, (50 to 80 nm in diameter), and a few complete virus particles, (45-65 nm in diameter), were seen in cisternae of rough and smooth endoplasmic reticula of hepatocytes, clusters or scattered core particles, (35-38 nm in diameter), were seen in the cytoplasm, some core particles were found in nuclei of liver cells where core assembly might be occur. The similarities and differences of the localizations of DHBV and HBV in duck liver cells are discussed.