Total and differential somatic cell counts in secretions from noninfected bovine mammary glands: the early nonlactating period.

Total somatic cells in secretions of nonlactating bovine mammary glands remained less than 5 x 10(5) cells/ml for the first 3 days after the last milking. Macrophages predominated the 1st day, and polymorphonuclear neutrophils were most common during the 2nd and 3rd day. The total somatic cell count was highest about 10 days after lactation ceased, and counts of 2 to 3 x 10(6) cells/ml were common. Equal numbers of macrophages and polymorphonuclear neutrophils were observed. Total cell populations gradually decreased during the period from 10 to 25 days of the nonlactating period.