Autumn-calving is fast approaching on farms and autumn-calving cows, are more susceptible to milk fever than their spring-calving counter parts.

It is important to get the management of autumn-calvers right in the lead up to calving. This will help to make the calving season easier, resulting in healthier calves and minimising the loss of body condition in early lactation.

What is milk fever?

Milk fever is characterized by reduced blood calcium (Ca) levels. It is most common in the first few days of lactation when the demand for Ca for milk production exceeds the body’s ability to mobilise calcium reserves.

Milk fever can also be seen in late-pregnancy, right up to the point of calving.

Dry cow nutrition

Your autumn-calving cows should of been body condition scored (BCS) at drying-off and fed accordingly.

It can be very easy for cows to become overfat during the summer months at grass. This leads to issues during calving and early lactation.

Minerals

Like their spring-calving counterparts, minerals are essential for autumn-calving cows. Correct mineral supplementation helps to prevent issues at calving and into early lactation.

Good quality minerals should be fed four to six weeks pre-calving, practically when cows are dry at grass in late summer. A bolus cannot replace minerals being fed daily to cows pre-calving.

Steps to preventing milk fever in autumn-calving cows:

  1. Have cows in the correct BCS at calving (3 to 3.25);
  2. Reduce calcium intake before calving and avoid any added oral calcium. This will allow the cow to mobilise her own calcium from bone or blood immediately after giving birth;
  3. Avoid lush pasture for autumn-calving cows, as this grass is low in magnesium;
  4. Feed a good quality, dry cow mineral that is high in magnesium and has either no added calcium or low added levels;
  5. Feed forages that are low in potassium and have not received potassium fertiliser or slurry.