Calving at two cuts feed and management costs

Did you know that growing heifers well to calve at two years will save on feed and management costs?


1. Feed. It’s cheaper to put weight on heifers earlier, that’s a proven fact simply due to feed conversion efficiency (FCE) being optimum in young animals.

Heifer replacement FCE is highest in the first eight weeks of life after which it rapidly tails off. In the first two weeks, 100g of feed will give approximately 50g – 60g of growth, thereafter it dramatically falls during the first 12 months of life at which point 100g feed will only give approximately 9g of growth. The following graph clearly shows these trends.

Heifer feed efficiency


Source: IRTA

*(Average daily gain) / (dry matter intake) x100

Feeding for growth has also proved to be cost effective according to study results from the Institute of Research and Technology in Agrifood (IRTA). To achieve average age at first calving at 23 months and a body weight of 650kg, feeding a total six litres of milk per day to weaning at two months resulted in the lowest total rearing feed costs. Heifers fed four litres during the same period had some catching up to do later on when FCE is lower. The following table logs the study results.

Milk volume fed and the impact on total heifer rearing costs
(calving 23 months, 650kg body weight)

Volume milk fed (l/day) during first two months Average weight gain during first two months (kg/day) Total rearing feed cost (£)
4 0.5 759
6 0.8 729
8 1.0 738

2. Management: if you are optimising your heifers’ early growth, then there is every chance this will lead to reduced time spent feeding and managing them in the service to calving period. Furthermore, calving them in to the herd sooner, helps to maintain a compact calving pattern, particularly in seasonal block calving herds.

Calving at two: Yields real financial benefits


Each of your heifer replacements is costing an average £1,800 to rear to first calving; that’s the second biggest expense on your unit according to a Royal Veterinary College (RVC) study. So the sooner they calve, the sooner you’ll get a return on that massive investment.

For every heifer which calves after the targeted 24 months, it’s going to cost another £50 per month, based on the RVC study rearing cost figures of £1.64 a day. If your average age at calving is 30 months, that’s taking rearing costs to well over £2,000 a head. Furthermore those heifers have been proven to be less fertile and less productive in later life.

Let’s take another look at one of the RVC studies featured in a previous blog. It concluded that heifers calving at 23 to 25 months of age produced the highest volume of milk over five years of life simply because they achieved more lactations in those five years, and had higher survival rates due to better fertility.

Heifers calving at under 23 months fitted a whole extra lactation into the same time period from birth. These animals calved for a third time at 50 months of age, whereas heifers calving for the first time at over 30 months only calved for a second time at 50 months.


Check out the study findings in the following table.

Age at first calving and yield

  Age at first calving (months)
<23 23-25 26-30 >30
Lactation 1
     305 day yield, kg 8494 8811 9103 8914
Lactation 2
     305 day yield, kg 9340 9908 10546 9633
Five years of life
     Total five year milk yield, kg 21072 22477 20605 15777
     % life in first five years spent in milk 46% 45% 40% 34%
Number of cows at third calving 62% 70% 59% 50%

Source: RVC

This RVC study consisted 445 heifer calves recruited from 17 dairy farms.

How to reduce rearing costs and time to age at first calving? Have a look at our new tool kit, which is designed to help all dairy producers grow better cows. The programme enables you to create your own heifer road map which sets individual farm objectives and helps you to track performance and continually review to ensure each animal is on target to reach puberty by nine months, first breeding by 13 to 14 months and in calf by 15 months.