With the initiation of lactation and continued milk production, tremendous adaptations occur in the dairy cow because of the increased need for nutrients to support milk synthesis. Besides the increased need for energy and amino acids for colostrum and afterward for milk synthesis, the requirement for calcium increases two- to three-fold over that required by the dairy cow before calving. Shortly before calving, a dairy cow deposits 8 to 10 g/d of calcium into her fetus, but when she calves, 20 to 30 g/d are secreted into colostrum and milk.
Thus, metabolic adaptions must take place to support the increased need for calcium. If they do not take place soon enough or of sufficient magnitude, the concentration of calcium in the blood drops below a critical threshold and clinical and subclinical hypocalcemia, or milk fever, can result.
In a recent Dairy eXtension webinar, Dr. Gary Oetzel, UW-School of Veterinary Medicine Food Animal Production Medicine, covers various aspects of treating and preventing subclinical hypocalcemia. In addition to the efficacy of dietary means of prevention, he discusses oral calcium supplements and how the calcium source can affect response. To learn more about Treatment and Prevention of Subclinical Hypocalcemia
Source:uwex.edu