Animal groups

Heifer nutrition

From four months to first calving: growth targets for each stage, how to feed them and what to avoid, so heifers calve at 22–24 months at the right size.

Growth targets by age

Overview

Heifer rearing is the second-largest cost on a dairy farm. Heifers that calve at 22–24 months at the right size are cheaper to raise and produce well without calving problems. Weigh or tape-measure them regularly; you cannot manage what you do not measure.

Key points

Breed at about 55% of mature body weight (often 13–15 months for Holsteins).
Calve at about 85% of mature body weight (measured after calving).
Aim for a steady daily gain of roughly 0.8–0.9 kg from weaning to calving.
Measure every 2–3 months and compare with the table; adjust the ration of groups that fall behind or get too fat.

Example targets for Holstein heifers (mature weight ~700 kg)

Age	Body weight	Wither height	BCS
Birth	40 kg	–	–
2 months (weaning)	80–85 kg	~85 cm	–
6 months	190–200 kg	~105 cm	2.5–2.75
12 months	340–360 kg	~122 cm	2.75–3.0
13–15 months (breeding)	~385 kg (55%)	~127 cm	3.0–3.25
22–24 months (after calving)	~595 kg (85%)	~137 cm	3.25–3.5

Target

Age at first calving 22–24 months.

Young growing heifer

4–6 months

The rumen is now functional but still small. Heifers need a nutrient-dense ration: good-quality forage plus concentrate, not straw-based diets.

Key points

Ration of about 16–17% crude protein in DM.
Good-quality hay or haylage plus about 2–2.5 kg concentrate per day; introduce silage gradually.
Provide a heifer mineral–vitamin premix and free access to clean water.
Keep groups even in size; small heifers lose out at the feed bunk.

Target

Daily gain of about 0.8–0.9 kg; about 190–200 kg at 6 months.

Before puberty

6–12 months

Between about 3 and 10 months the udder grows faster than the rest of the body. Too much energy in this period deposits fat in the developing udder and can reduce future milk yield. Puberty comes at about 40–45% of mature weight (usually 9–11 months).

Key points

Ration of about 14–15% crude protein in DM; balance energy and protein rather than pushing energy.
Forage-based ration with about 1.5–2.5 kg concentrate, depending on forage quality.
Avoid daily gains above about 0.9–1.0 kg on high-energy diets (for example, unrestricted corn silage).
Watch body condition: aim for about 2.75–3.0, not fatter.

Target

About 340–360 kg and ~122 cm wither height at 12 months, without over-conditioning.

Breeding period

13–15 months

Size, not age, decides when a heifer is ready to breed. Heifers bred too small have more calving difficulty; heifers bred too late cost more and calve too fat.

Key points

Breed at about 55% of mature weight (~385 kg) and ~127 cm wither height for Holsteins.
Ration of about 13–14% crude protein; avoid sudden drops in energy around breeding.
Trace minerals and vitamins (selenium, copper, zinc, iodine, vitamins A and E) support fertility; use a balanced premix.
Body condition about 3.0–3.25 at breeding.

Target

First-service conception rate of 60% or more in heifers.

Pregnant heifer

15–21 months

The pregnant heifer is still growing. She needs steady growth for her own body and, in the last months, for the calf, but she must not get fat.

Key points

Ration of about 12–13% crude protein, mostly forage.
If corn silage is the main forage, dilute energy with straw or lower-energy hay to prevent fattening.
Keep minerals and vitamins balanced all the way through pregnancy.
Over-conditioned heifers have more calving difficulty, retained placenta and ketosis after calving.

Target

Steady gain of about 0.8 kg per day; body condition not above 3.5.

Before calving (close-up)

Last 3 weeks

The last three weeks prepare the heifer for her first lactation. The goal is to keep dry matter intake up and to get the rumen used to the lactation ration.

Key points

If possible, group close-up heifers separately from older cows; they lose out in competition.
Introduce the main ingredients of the lactation ration in small amounts.
Heifers rarely get milk fever, so a strongly negative DCAD ration is usually not needed; balance protein and energy carefully.
Provide at least about 75 cm of feed-bunk space per heifer and comfortable, clean bedding.

Target

Calving at 22–24 months, body condition 3.25–3.5 and about 85% of mature weight after calving.

Download this guide as a PDFThe PDF version and printable farm forms are available to approved members.Member login →

Educational content with general guidance; targets vary by breed and farm. Diagnosis and treatment of sick animals are your veterinarian’s job.

Want a program tailored to your farm? Let’s talk.Get consulting