Milk Fever and Hypocalcaemia in Dairy Cows

Milk fever, caused by low blood calcium around calving, is one of the most common metabolic disorders in high-producing dairy cows. Prevention and prompt treatment are essential for cow welfare and farm productivity.

Key Facts

Milk fever affects approximately 5 to 10% of dairy cows in intensive systems, with rates higher in older cows
Blood calcium plummets at calving as the mammary gland suddenly demands large quantities for colostrum
Clinical signs include muscle weakness, sternal recumbency, cold extremities, and loss of consciousness
Untreated clinical milk fever is fatal within 12 to 24 hours without intervention
Subclinical hypocalcaemia, with no obvious symptoms, is even more common and impairs immune function
Intravenous calcium borogluconate is highly effective and rapid-acting as treatment
Dietary management in the dry period significantly reduces incidence

Welfare Considerations

Cows with milk fever experience profound muscle weakness, inability to stand, and distress. Even mild subclinical hypocalcaemia impairs immune function, increasing susceptibility to mastitis, retained foetal membranes, and other periparturient diseases. The welfare cost extends beyond the immediate episode — cows that go down and cannot rise quickly develop pressure sores and secondary muscle damage. Prevention through anionic salt supplementation or carefully managed calcium-restricted dry cow diets dramatically reduces incidence and associated suffering.

What You Can Do

If you manage dairy cattle, implement evidence-based dry cow transition programmes to prevent hypocalcaemia
Train farm staff to identify early signs of milk fever and administer calcium quickly
Ensure fresh-calved cows are checked regularly during the first 48 hours after calving
Support research into low-stress transition cow management that reduces metabolic disease
Choose dairy products from farms that publish data on metabolic disease incidence