Spontaneous Humeral Fractures in Heifers

Humeral fractures (upper front leg) in heifers are no laughing matter. Every year we have many farms affected in this practice, sometimes losing up to 10% of their heifer line. We see two peak periods of these fractures. The first, +/- one week of calving and the second coinciding with peak lactation (we have found heifers that break legs at peak lactation are in the top 10% producers at the first herd test).

We know that the bones of these heifers have osteoporosis (thinned), and this is likely due to excessive mineral loss in late gestation and peak lactation. Heifers that are in a surplus dietary calcium status will not need to mobilise bone calcium. If dietary limeflour is supplied in excess of requirements through the last month of pregnancy and also the early lactation period (up to mid-November) at about 100g/heifer day. Avoid providing heifers high dose anionic salts (mag sulphates and mag chlorides) as these may enhance the release of bone minerals.

These heifers also have a high copper consumption, so it is important to support this with good supplement levels going into the winter.