Cull or Keep Calculator
a simple 12-month comparison.
Compare the next 12 months of keeping a cow with selling her and bringing in a heifer, using your own milk price, feed cost, cull value and heifer price.
Keep or Replace?
Enter milk in litres (or kg, if you sell by kg) and the price for the same unit.
The cow
The replacement heifer
Next 12 months
How the Comparison Works
A deliberately simple, one-year look at the money.
If kept: the cow's milk over the next 12 months times the milk price, minus a year of feed. If replaced: the cull value you get now, minus the heifer's price, plus the heifer's milk in her first 12 months, minus a year of feed.
A heifer is still worth money after a year, and so is a cow you keep. If you leave the two "value after 12 months" boxes blank, the whole heifer price counts against one year, which makes keeping the cow look better than it is. Fill them in for a fairer comparison.
Money is only part of the decision. Also think about the cow's health (mastitis, lameness), her genetics, her pregnancy status and the risk a bought-in heifer brings into the herd.
How to use this calculator
- Choose your currency. Enter the milk price you are paid per litre (or per kg, if you sell by kg) and the average feed cost per animal per day. The same feed cost is used for the cow and the heifer.
- Under The cow, enter the milk you expect from her in the next 12 months, whether she is pregnant, and what she would sell for today.
- Under The replacement heifer, enter what a replacement would cost you and the milk she is likely to give in the same 12 months. A heifer gives no milk until she calves. If you would use one of your own heifers, enter what she would sell for.
- If you can, fill in both "value after 12 months" boxes with what each animal would be worth a year from now.
- Change one figure at a time, such as the milk price or the cow's milk, to see how firm the answer is.
Reading the result
Difference shows which choice leaves more money at the end of the year, and by how much. A small difference means money alone does not settle it, so let her health, fertility and genetics decide. A large difference in favour of replacing is a good reason to look closely at that cow, but only if you can really get a healthy heifer at the price you entered. Treatment costs are not included: if the cow keeps getting mastitis or lameness, keeping her will earn less than the figure shown.
Common questions
What milk figure should I use for an older cow?
Use her own records: her last lactation and what she gives now. Count only the milk she will give in the next 12 months. A cow that is late in lactation, or open and unlikely to calve soon, will give much less than a full lactation in that time.
Is the calf she is carrying counted?
No. A pregnant cow will also give a calf, and its value is not counted. If the calf matters to you, add a rough value for it to her "value after 12 months".
Is buying in a heifer risky?
It can be. Bought-in animals can bring new diseases into the herd. Ask the seller for health and vaccination records, keep new arrivals apart from the herd at first, and ask your vet which tests to do before mixing them in.
Decision support only. Not a substitute for your veterinarian.