Calving at two: essential for herd profitability

Dairy cows don’t become profitable until halfway through their second lactation. True or false?

True. It’s a fact that each of your heifer replacements is costing an average £1,800* to rear to first calving, a figure which represents around 20% of farm costs and the second biggest expense on your unit. So the sooner they calve, the sooner you’ll get a return on that massive investment, particularly since the return on that initial investment is not earned until at least the second lactation.


If you target 24 months age at first calving, then your heifers will achieve 10 months more profit producing production than one calving at 30 months which won’t break even until well in to their third lactation.

That’s not all, heifers calving at 24 months have better fertility, they have higher milk yields and have the highest survival rate over a five year period, and consequently fewer replacements will be required leaving surplus heifers which can potentially be sold as an additional income stream. Irish studies have concluded that calving at 23 to 25 months old resulted in, up to an extra £2,300 of milk income per cow over five years when compared to calving at 30 months.


The following table, Figure 1 offers some pointers to achieve the 24 month calving target.

Fig 1: Essential growth targets
Birth to weaning Double body weight
Puberty 45% mature weight
Breeding and pregnancy 55 – 60% mature weight
First lactation post calving body weight 82 – 85% mature weight

Your goal is to achieve 82 – 85% mature size at first calving and achieving a first lactation yield of 80% of the mature cow. For mature weight, that figure is determined at the middle of the third and fourth lactation, 80 to 200 days in milk on healthy cows, not culls.

  • If your heifers have yet to calve in the 23 to 25 month bracket, then take a look at our new tool kit, Feed For Growth 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.

*A.C. Boulton, J.Rushton & D.C Wathes