The objectives of this project are: 1. Generate adequate information to understand the relationship between Somatic Cell Count (SCC), Diffrential Cell Count (DCC) and mastitis (intramammary infections) in dairy herds. 2. Develop guidelines to cost effective monitoring and control of mastitis in dairy cattle herds that should be offered with the commercail DCC product 3. Develop a commercial DCC product that will be used to automate the counting of DCC