An indirect fluorescent antibody test for the detection of Cytauxzoon-like organisms in experimentally infected cats.

Antiserum to feline Cytauxzoon-like parasites was used in conjunction with labeled rabbit antisera to feline globulins to detect the presence of Cytauxzoon-like parasites in spleens of experimentally infected cats. Frozen spleen sections from 21 infected cats showed positively fluorescing masses within splenic veins and a diffuse scattering of discretely fluorescing cells in the red and white pulp. The distribution of fluorescence corresponded with the appearance of parasitized reticuloendothelial cells in histological preparations of spleen tissue. This indirect fluorescent antibody test consistently detected the presence of Cytauxzoon-like parasites in frozen spleen sections from experimentally infected cats.