Somatic cell count.

The somatic cell count (SCC) is the number of cells present in milk (body cells as distinguished from invading bacterial cells). It is used as one indicator of udder infection. Somatic cells are made up of a combination of white blood cells and epithelial cells. White blood cells enter milk in response to inflammation, which may occur due to disease, or occasionally to injury. Epithelial cells are shed from the lining of the udder tissue. White blood cells make up the majority of the somatic cells, especially when the cell count is raised. This chapter describes why cell counts are important, how they can be measured, the factors that result in raised counts and action on high cell count cows, along with an example of how individual cell count data can be used.