Implementation of immunohistochemical methods in diagnostics of bovine sarcocystosis

Bovine sarcocystosis was examined in three age categories of cattle using direct and immunohistochemical methods. The direct methods of compression, trypsin digestion and a histological method were applied, and the applied immunohistochemical methods included peroxidase antiperoxidase (PAP), the highly sensitive streptavidin biotin immunoperoxidase complex technique (LSAB+) and indirect immunofluorescence (IF). Primary rabbit antiserum obtained for the zoites Sarcocystis cruzi syn. S. bovicanis was used for all immunochemical and immunohistochemical examinations. Cross reactivity was determined using primary rabbit antiserum to antigens of S. ovifelis zoites. Both primary antiserums were produced in the laboratory, as no commercial preparations were available on the market. The evaluation of the sensitivity and efficacy of the immunohistochemical methods was performed on the grounds of comparisons with the direct methods: compression, trypsin digestion and a histological method. The applied immunohistochemical analyses are very specific in proving sarcocystosis in cattle, especially the LSAB+ technique, and, according to their sensitivity in detecting this infection, they are similar to the method of trypsin digestion. The obtained rabbit antiserum against antigens of S. bovicanis zoites yielded good results in the diagnosis of the homologous specie. Proven cross reactivity of the homologous and heterologous antiserums and antigens, as an immunochemical reaction of complete identity in one part to the antigen structure, was established in primary rabbit antiserum to S. ovifelis zoites, which indicates that heterologous antiserums can also be used in immunohistochemical reactions in the diagnostics of bovine sarcocystosis. .