Somatic cell count (SCC) is an important measure of milk quality. A high SCC reduces the processing quality of the milk and it indicates a high level of infection in the herd, either clinical or sub-clinical mastitis.

February can often be a bad month for SCC, with some high levels recorded, particularly in the first few loads of milk delivered to the co-op. SCC levels above 400,000 cells/ml are not uncommon, even in herds which normally have relatively good SCC.