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1 | Dairy heifer nutrition
Dairy heifer nutrition
This Infosheet covers
• The post-weaning nutrition of heifers.
• Feed composition: energy, protein and dry matter levels.
• Balancing heifer diets to meet growth rate targets.
• Mineral requirements.
• Water requirements.
Key points
• Heifers are most feed efficient when they are young (small); try to capitalise on early growth efficiency.
• Nutrition pre-puberty (before 50% mature liveweight) influences skeletal growth.
• Growth rates give the best indication of whether heifers’ nutritional requirements are being met.
• Heifer diets need enough energy (10.5 MJ ME/kg DM or higher) and protein to achieve target growth rates.
Often pasture alone will be sufficient.
• Heifers require adequate mineral levels and available water.
Impact of age on nutritional requirements
• As heifers grow, their requirements change and the feeding levels and make-up of their diet should change as
well. Matching the type of feed, and its composition, to a heifer’s nutritional requirements is key to meeting
growth targets. There are three post-weaning nutritional stages:
• Weaning to nine months
This is a critical stage. Studies have identified that pre-puberty (before heifers reach 50% of their mature
liveweight) is when nutrition most affects skeletal growth1. Improved skeletal development will result in taller
heifers that suffer fewer problems at calving. It is important to stimulate lean body growth (muscle and skeleton)
without encouraging the deposition of excessive fat. This will increase a heifer’s frame size, as opposed to just
increasing body condition score.
For dairy animals typical to New Zealand2, growth rates from weaning of 0.7 kg/day in Holsteins and 0.5 kg/
day in Jerseys are required to achieve target weights. A diet high in energy and protein should be provided,
particularly as heifers’ rumen capacity may be limited during this stage (see Table 1).
To give heifers lush new pasture we do a cut of silage at the runoff before the calves go out.
Dairy farmer, 320 cows, Rerewhakaaitu, Bay of Plenty
We’ve had to look at our management over the first year of life. In the past heifers came home at
22 months and they were in good condition but not very well grown.
Dairy farmer, 320 cows, Hawera, Taranaki
FARMER VIEWPOINT
2 | Dairy heifer nutrition
1Macdonald, KA, JW Penno, AM Bryant, and JR Roche. 2005. Effect of feeding level pre- and post-puberty and body weight at first calving on growth, milk production, and fertility in grazing dairy cows. Journal of Dairy Science. 88:3363-3375. 2DairyNZ 2016. Breed category averages. New Zealand Dairy Statistics. Page 32 3Handcock, RC, TJ Lopdell, LR McNaughton. 2016. More dairy heifers are achieving liveweight targets. Proceedings of the New Zealand Society of Animal Production. 76:3-7 4Based on calculations from Ian Brookes, Growing replacement heifers. Massey University, Palmerston North
Use heifer weights to see if heifers have been fed enough, we don’t measure feed intakes at the
runoff—we go off weight gain.
Dairy farmers, 265 cows, Inglewood, Taranaki
Putting weight on heifers in the autumn can be difficult. Even though our autumn grass looked like
rocket fuel, I started weighing and it showed the heifers weren’t gaining any weight. Sometimes the
dry matter is too low in the pasture.
Contract grazier, 850 heifers, Stratford, Taranki
• Nine months to mating at 15 months
During this period, heifers do not require a diet as high in energy and protein as younger heifers; however, they
require more feed to meet their maintenance and growth requirements. Heifers should have a progressively
increasing feed allocation, particularly when they are due to be mated.
• Older heifers
At this stage, a feed with a lower energy density can be used to maintain growth rates. Care should be taken in
the period coming up to calving. Attempting to make up for lost growth just before calving can result in overly
fat heifers (higher body condition) and/or overly large calves. Body condition reflects how well an animal has
been fed for the previous 6-8 weeks, whereas a longer period of good nutrition is required to convert feed into
body frame. New Zealand farm data3 indicates that heifers do not typically put on the necessary weight during
the autumn before their first calving; the cause of this is unknown.
Feed composition
Energy and protein requirements
All animals require energy for maintenance i.e. the energy required to sustain basic functions, such as normal metabolism,
and physical activities, including walking and eating. Growing animals also require energy for liveweight gain.
In New Zealand, the energy in a feed is expressed as megajoules of metabolisable energy per kilogram of dry matter
(MJ ME/kg DM).
As animals become heavier they become less efficient at using energy for growth. For example, a heifer weighing 100
kg requires about 20 MJ ME to gain a kilogramme of liveweight, whereas a 400 kg heifer requires double that i.e. 40
MJ ME (see Figure 14). Therefore, it is important to try to capitalise on energy efficiency when animals are young.
FARMER VIEWPOINT
We prioritize feeds by their protein content over the winter, the lighter animals get the higher
protein feeds. The lightest heifers are fed on all grass, the medium weight animals get turnips and
swedes, and the heaviest heifers get fodder beet.
Contract Grazier, 2,400 heifers, Mossburn, Southland
FARMER VIEWPOINT
3 | Dairy heifer nutrition
Figure 1. Intake requirements of dairy heifers for a) maintenance only and b) for growth at different growth rates
(assuming feed energy value is 11 MJ ME/kg DM).
Current liveweight
100 kg
Maintenance intake
requirement =
1.6 kg DMday
Current liveweight
100 kg
Maintenance intake
requirement =
1.6 kg DMday
Calculating heifer intake requirements - example
Growth rate
0.6 kg/day
Growth intake requirement =
1.2 kg DM/day
Growth rate
0.6 kg/day
Growth intake requirement =
1.3 kg DM/day
Total intake required
1.6 + 1.2 =
2.8 kg DM/day
2.2 + 1.3 =
3.5 kg DM/day
The example shows how much heifers’ energy requirements change as they grow.
Monitoring heifer growth rates and comparing them with their expected weight gain will give a good indication if
the feeding programme is on track. Table 1 shows the energy and protein required at different liveweights for good
heifer rearing.
5
4
3
2
1
0
6
100 150 200 250 300 350 400 450 500
Current liveweight (kg)
Inta
ke (
kg D
M/h
a/d
ay)
1.62.2
Intake requirements for maintenance only
5
4
3
2
1
0100 150 200 250 300 350 400 450 500
Current liveweight (kg)
Inta
ke (
kg D
M/h
a/d
ay)
1.31.2
Intake requirements for growth only at different growth rates
0.4 kg/day 0.6 kg/day 0.8 kg/day 1.0 kg/day
4 | Dairy heifer nutrition
Table 1. Energy and protein required by heifers of different liveweights, to meet their maintenance needs and target
growth rate.4
NB. Pregnancy energy requirements are not included.
Dry matter intake
Predicting the dry matter intake of dairy heifers is an important part of heifer rearing, but it can be difficult to
estimate because:
• Heifer dry matter intake as a percentage of liveweight decreases as liveweight increases, but the relationship is not direct.
• Dry matter intake is influenced by dietary fibre, but the influence decreases as liveweight increases—this is one of
the reasons that feeding high quality feed to young animals is so important.
Balancing diets to meet target growth rates
Grazed pasture is the cheapest feed source for growing cattle on most farms. If pasture quality is good enough i.e. 10.5
MJ ME/kg DM or higher, heifer growth rate targets can be met by using pasture alone, even with Kikuyu if it is leafy.
If pasture quality (due to excessive stem or dead material) or quantity (due to poor plant growing conditions) are
lacking, supplementation may be required to maintain heifer growth. Supplements should contain at least 11 MJ ME/
kg DM, and crude protein levels which are suitable for the animal’s nutritional stage.
Pasture characteristics required
To sustain high heifer growth rates, pasture should:
• be between 9 and 20 clicks on the plate meter, or
• 2500 on a sward stick, and
• contain at least 15% clover, and
• be predominantly made up of green and leafy material (low in stem and dead plant material).
Liveweight Energy Protein
Maintenance Growth rate per 1 kg
Kg MJ ME/day MJ ME/day %
100 19 17 17
150 26 24 17
200 32 28 17
250 37 29 15
300 42 31 15
350 47 39 14
400 51 40 14
450 55 40 14
500 62 40 14
550 69 40 14
5 | Dairy heifer nutrition
Mineral requirements
Heifer mineral requirements should not be overlooked. These will vary due to various factors, including: forage
mineral levels, which will be affected by the soil type and fertiliser applications; supplementary feed utilisation;
and the interactions between minerals . For example, selenium deficiency can be an issue particularly on peat soils;
sodium may need to be supplemented when lucerne is fed; and as copper is bound by zinc, copper deficiency can
become an issue during the facial eczema season as zinc is used for control.
More information
• For more on heifer mineral requirements and treatment, see Heifer Infosheets: Trace Elements and Heifer
Infosheets: Trace Element Treatment.
• Further information is available in the Heifer Infosheet covering crops and supplements.
More information
• For more on use of a sward stick, see Beef + Lamb Fact Sheet Measuring Pasture Covers Using the Sward Stick (http://
beeflambnz.com/Documents/Farm/Measuring%20pasture%20covers%20using%20the%20sward%20stick.pdf).
With our paddock sizes we don’t put heifers in paddocks with pre-grazing covers greater than 2800,
I’d rather they go in to shorter feed than longer for feed quality.
Contract grazier, 150 heifers, Cheviot, Canterbury
To make sure we give heifers quality feed our grazing system doesn’t graze heifers in paddocks with
pasture covers greater than 2500 and we don’t graze harder than 1500. One of my clients went from
having 90% heifers below target before the system to 90% on or above target by using the system.
Grazing consultant, Winton, Southland
I think heifers need daily shifts so paddock subdivision needs to be small enough for the mob size.
Dairy farmer, 750 cows, Awanui, Northland
To make sure heifers are being offered quality feed on dryland pastures, we shift the heifers before
it looks like they need shifting.
Contract grazier, 720 heifers, Oamaru, North Otago
FARMER VIEWPOINT
6 | Dairy heifer nutrition
More information
• For more on feed budgeting see DairyNZ Facts and Figures (https://www.dairynz.co.nz/media/2816711/
facts-and-figures-dairynz.pdf) and DairyNZ Farm Fact 3-21: Feed requirements for grazing dairy heifers
(https://www.dairynz.co.nz/media/3038271/feed-requirements-for-grazing-dairy-heifers-3-21-web.pdf).
• For more about feeding heifers see Heifer information: Dairy Heifer Nutrition.
Water requirements
Access to clean, fresh water is important for rumen function, metabolism and health. Inadequate levels will restrict heifer growth.
The water contained in feed will meet some of a heifer’s water requirements, but additional drinking water is essential.
Heifers require 3-6 litres water/kg DM eaten; the amount will vary depending on the air temperature5, the diet’s water
content, and mineral salt intake. During hot weather more water will be required to help regulate body temperature. Table
2 shows the expected water intakes of heifers of different liveweights at two different ambient temperatures6.
Table 2. Estimated water intake (litres/day) required by heifers, at two different ambient temperatures.
Air temperature (° C)
Liveweight (kg) 4 27
45 3 4
90 8 13
180 14 23
270 19 32
360 24 40
455 28 47
5Holmes, CW, IM Brookes, DJ Garrick, DDS Mackenzie, TJ Parkinson, and GF Wilson. 2007. Nutrition: Quantitative requirements of dairy cattle, Chapter 14. Milk Production From Pasture. Published: Massey University, Palmerston North. 6Heinrichs, AJ, LA Swartz. Management of dairy heifers. Penn State Extension circular 385. Pennsylvania State University, Old Main, State College, Pennsylvania. Available: http://extension.psu.edu/animals/dairy/nutrition/heifers