A rapid staining procedure for Anaplasma marginale in bovine erythrocytes.

A commercial product that stains cells in less than 1 minute was compared with the Giemsa and the Wright-Giemsa methods for detection of the intraerythrocytic parasite, Anaplasma marginale, in bovine blood smears. The total number of A marginale-infected erythrocytes detected in 5 microscope fields of 18 different samples was determined for each staining procedure. In samples where less than 2% to greater than 25% of the RBC were infected, statistical analysis of the data indicated that the rapid staining method was superior to the Giemsa and Wright-Giemsa methods with regard to determination of the percentage of bovine erythrocytes infected with A marginale.