mastitis is an inflammation of the mammary glands and the most important cause of economic loss in the modern dairy industry. Losses associated with mastitis are notoriously difficult to estimate from treatment costs, culling, mortality, and reduction in milk yield. Because Disease recording systems that collate data from large numbers of farms are not yet widespread worldwide and the low heritability of mastitis, Therefore, selection for mastitis resistance is often based on genetically correlated indicator traits such as somatic cell count (SCC). The genetic correlation between clinical mastitis (CM) and SCC is high, suggesting that selection for low SCC reduces the incidence of mastitis. The high genetic correlation between SCS and clinical mastitis makes SCC a useful predictor of clinical mastitis.
