P2g: Heifers Early Calving

The age that dairy heifers calve into a milking herd for the first time can play a significant role in their health and welfare and the economics of a dairy farm business.

Australian dairy farmers with seasonal/split calving systems generally aim to calve their cows at about 2 years of age. In some Australian dairy herds, the actual age of first calving is closer to 3 years.

While it is possible to breed heifers to calve at less than two-years-of-age – and some dairy farmers do – there’s limited research regarding the best age of first calving and what this means for the heifer across her lifetime and how this contributes to her return on investment.

Benefits

The findings from this research will provide a clearer understanding of what age is best for a Holstein heifer to calve for the first time.

This will enable dairy farmers to focus on growing-out their heifers – with optimum nutrition – to ensure they meet target breeding weight at this ideal age.

The findings should also provide clearer direction for the management of heifers and breeding plans, including fixed time AI programs.

In addition, this research should determine the return on investment for heifers and quantify the cost of “unproductive” animals on the farm – those that aren’t producing milk.

Other benefits could also include understanding when to alter the age of first calving for improved economic returns. For example, when the farmgate milk price is low or if the cost of rearing calves is high.

Progress