WHY DOES MILK FEVER OCCUR?

99% of calcium in the cow’s body is stored in the bones and teeth. The rest circulates in the blood and needs to be maintained within a narrow range5.

WITH THE ONSET OF LACTATION THERE IS A SUDDEN AND MASSIVE DEMAND FOR CALCIUM: AN EXTRA 80g PER DAY2.

The cow can adapt to this change by drawing on her own calcium reserves (bone and tissues), improving absorption from the diet and by reducing losses in the urine5,8. This adaptation occurs with the help of the cow’s calcium homeostatic mechanisms.

There is a balance between lactational calcium demands and the ability of a cow to mobilise her own calcium reserves to meet this demand.

The cow’s ability to maintain this balance and meet demands influences whether
or not milk fever develops; in those cows unable to maintain this balance,
milk fever develops9.