Interactions between Metabolic Disease and the Immune System: Why Cows Are Likely to Develop Mastitis at Freshening

The transition from pregnant, non-lactating to non-pregnant, lactating is too often a disastrous experience for the cow. Most of the metabolic diseases of dairy cows milk fever, ketosis, retained placenta (RP), and displacement of the abomasum occur within the first two wk of lactation. In addition to metabolic disease, the majority of infectious disease experienced by the dairy cow, especially mastitis, but also diseases such as Johne's disease and Salmonellosis, become clinically apparent during the first two wk of lactation.