Cytospin centrifuge in differential counts of milk somatic cells

A procedure was developed for a cytospin centrifuge to concentrate cells from milk onto microscope slides in a circle with 6 mm diameter. Differential somatic cell counts with cytospin were compared to the conventional hand smearing technique to ascertain variation in differential counts. Milk samples were from each of 30 cow quarters, 10 within each of three total milk somatic cell count ranges of less than .7, .7 to 1.5, and more than 1.5 x 10(6)/ml. Two prepared from each sample. All smears were air dried; and stained with modified Wright's stain, the first 200 cells were counted. Differential cell counts from smears prepared by the two procedures were not different. Variation between duplicate smears in differential cell counts was less for cytospin technique. Cytospin can be used to obtain rapid and accurate differential cell counts in milk over a wide range of total somatic cell counts.