The use of immunofluorescence and immunoperoxidase staining in studying the pathogenesis of chicken anaemia agent in experimentally infected chickens.

Both the indirect immunofluorescence test and the avidin-biotin method of immunoperoxidase staining were reliable techniques for the demonstration of chicken anaemia agent antigen in frozen or Bouin's-fixed, paraffin-embedded tissue sections. The main target cells of infection were thymic lymphoblasts in the outer cortex of the thymus and haematopoietic stem cells in the bone marrow.