Most cows experience a drop in blood calcium concentrations at the start of lactation. For many cows, this is an example of normal subclinical hypocalcemia. However, most cows overcome this calcium imbalance quickly by activating calcium regulation pathways in the body. The cows that do not are dyscalcemic and can experience negative outcomes.

While often undiagnosed due to the absence of clinical signs and the price tag associated with collecting blood samples required for diagnosis, subclinical hypocalcemia (SCH) affects nearly 45 percent of multiparous dairy cows.

Subclinical hypocalcemia (SCH) is an invisible threat to both the dairy cow and producer. As nearly 45 percent of multiparous cows experience SCH during the early lactation period, producers can implement dietary strategies such as feeding negative dietary cation anion difference (DCAD) rations in the late dry period or administering prophylactic calcium treatments to fresh cows to minimize the risk of SCH.