An immunocytochemical study on the sequential tissue distribution of duck plague virus.

Primary replication and tissue distribution of duck plague (duck virus enteritis) virus in domestic ducks following oral infection were studied by an avidin-biotin-peroxidase complex (ABC) method of immunoperoxidase staining. The virus replicated primarily in the mucosa of the digestive tract, especially in the oesophagus as early as 24 h after infection, then spread to the bursa of Fabricius, thymus, spleen and liver. The epithelial cells and macrophages of these organs were the principal site of virus replication, although virus antigen was also found in lymphocytes. The antigen was localized both in the nucleus and cytoplasm of these cells.