Demonstration of Aujeszky's disease virus antigen in trypsin-digested paraffin-embedded tissue sections by immunofluorescence

After trypsin digestion of buffered formalin-fixed, paraffin-embedded brain section, immunofluorescent indication of Aujeszky's disease virus antigen was successful in experimentally infected cow and goat. This result was comparable to those obtained with light and electron microscopic examinations. This method will be diagnostically useful where fresh-frozen tissue is not available.