Formalin-fixed, paraffin-embedded tissue sections (bursa, spleen, Harderian glands etc.) obtained from broiler chicks infected with IBD virus under experimental conditions were examined for the presence of IBD virus antigen(s). We describe an immuno-peroxidase test for the detection of viral antigens. Precisely, the tissue sections were deparaffinised with xylene, endogenous activity quenched with 0.5% H2O2 in methanol. The non-specific binding sites of immunoglobulins were blocked with 10% BSA and normal rabbit serum (1:1) after treatment with anti-chicken unconjugated whole serum. IBD-specific serum and peroxidase conjugate were then added. Using DAB as chromogen, the tissue sections were counter-stained with haematoxylin. A positive reaction was demonstrable by development of intense brown colour. Lesions were scored based on intensity of colour and area showing positive reaction.
Immunoperoxidase, infectious bursal disease virus antigens, poultry
