Attention to detail: Part 2

Unlocking potential in the milk drinking phase

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This week we’re introducing four more fundamentals that will help you to unlock your heifer calves’ potential. Small management details like these can contribute towards their growth and the animals’ ability to hit required growth targets for 24 month calving.

Fact, if you increase your heifer calves’ daily liveweight gain from 500g to 800g in the milk
drinking phase, then they’ll have the potential to increase yield by an average 450 litres in the first lactation*.

1. Drinking angle

The strength of the oesophageal grove reflex is triggered by sucking, milk temperature and the position of the head. Consequently, calves need to drink from shoulder height to ensure neck extension, a weak groove reflex can cause milk to enter the rumen which can lead to problems such as bloat and scours. If you bucket feed, then raise the buckets to sit at least 30cm from the floor.



2. Consistency

Whatever you do – from the time of feeding to volume, concentration and
temperature of milk, dry feed and access to straw – be consistent. It’s vital to sustain intakes and growth.

3. Maintaining and cleaning feeding equipment

Check teats regularly – splits and wear and tear could lead to fast drinking and in turn, abomasal overflow and scour which could impact on growth. Check again to make sure the teats are set up right – the hole should be in a + position, not an x position, otherwise milk flow will be compromised.


4. Ambient temperature

Your calves have a thermal neutral zone of 15oC to 20oC, below which they will need more energy for maintenance and keeping warm. If this energy is not supplied, then growth rates and immunity could be compromised. Jackets are useful to keep calves warm from birth to three weeks, whilst ensuring they are bedded on clean, dry straw in a draught free environment.

Finally, measure and monitor: your heifer calves will need to gain 800g/day throughout
the rearing period if they are to double their birth weight by weaning and go on to reach 85
– 90% of mature weight by calving at 23 to 25 months, weigh your animals regularly to ensure they are hitting these targets

* Adapted from Soberon & Van Amburgh 2013

Attention to detail: Part 1

Unlocking potential in the milk drinking phase

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Did you know that if you increase your heifer calves’ daily liveweight gain from 500g to 800g in the milk drinking phase, then they’ll have the potential to increase yield by an average 450 litres in first lactation?

Unlocking that potential is all about attention to management detail. Here are five fundamentals.

1. Mixing: Don’t get confused!

If you are following instructions to make up one litre of milk, then you need to add 125g of calf milk replacer powder (CMR) to 875ml of water equating to a 12.5% concentration. Adding 125g of the same CMR to one litre of water will lower the milk concentration to 11.1%. On a system feeding six litres per day, that would equate to 4.7kg less CMR over a 56 milk day period.

Download our Farmers Guide to Mixing Milk here.

2.Scoop calibration: CMR is a natural product so bulk density can vary between batches.

Calibrate your CMR scoop between batches by measuring a level scoop and weighing it. Take a scoop holding 375g, but you think it holds 450g and you’re aiming to feed 900g per day, then you could be underfeeding by a significant 150g per day.

3. Scoop cleaning: do you regularly clean and dry your measuring scoop?

A scoop with a build-up of CMR could significantly impact on the amount you are actually feeding each day. For example, 5g of dirt or hard powder in a 150g scoop could mean you’re feeding 30g per day less than you thought when feeding daily 900g per day measured using a 150g scoop.

4. Mixing temperature: aim for 40°C.

Scalding temperatures will denature milk proteins and reduce the quality of milk solids fed.

5. Feeding temperature: aim for 37°C.

Milk should be fed between 37-39°C to stimulate a strong oesophageal groove reflex, which helps prevent milk entering the rumen. The spillage of milk into the rumen will increase the risk of scours or bloat which could result in poor growth rates. If you are feeding a long line of calves, ask yourself – is one at the end getting the same temperature milk as the one at the start? Think of ways around it, for example using a milk shuttle to keep the milk warm.

Inaccurate measuring over a prolonged period can impact pre-wean growth and your calves weaning date.

Next week we’ll investigate some more fundamentals.

Source: Adapted from Soberon and Van Amburgh, 2013

Measure for success

Do you want increase herd yield?

If your heifers calve at 23 to 25 months then they will go on to yield more over their first five years of life than older calving animals simply because they achieve more lactations per unit of time, and have higher survival rates according to a Royal Veterinary College study of 500 animals.


To calve at 24 months, heifers must be in calf by 15 months. Since maiden heifers require on average 1.4 services per conception, first breeding must start at 13 to 14 months.

FFG-Nutrition-AFC 24 months benefitsActions to take:

1. Set growth rate targets: ensure rapid growth in early life – they will never catch up. Aim for up to 0.85kg per day during the first three months of life, and thereafter 0.7kg per day up to first breeding when they must be 55% to 60% of mature body weight.

2. Measure calf growth: if you don’t, you can’t monitor. Measure heifers at least twice during the rearing period: at birth, when it’s relatively easy to put a new born calf on a weigh scale, at weaning and again at a time when animals are being handled, for example vaccination or worming. Use weigh scales or a weigh band.

Click here for a practical demonstration on Using a Calf Weighband or  find out more in our Farmers Guide – Growth Measuring Tools.

3. Milk: feeding sufficient energy and protein to support target growth rates is essential. Do you know how much milk powder your calves receive each day? For 0.6kg per day target growth rate, calves should be fed at least five litres of a 12.5% solution of milk replacer, that’s 125g of powder made up to a litre, providing the calf with 625g milk powder per day (125g x five litres = 625g).

If you target higher growth rates of 0.8kg to 0.9kg per day, feed up to 900g of milk powder per day in two or preferably more feeds, for example feed six litres of milk mixed at a concentration of 150g of powder per litre.

4. Weaning management: calves must be provided with fresh palatable dry starter feed from day three, plus high quality straw, to ensure good rumen development prior to weaning. A calf should be eating 1kg to 1.5kg a day of concentrate and doubling its birthweight at weaning. Adopting a gradual weaning protocol by stepping down the amount of milk fed and number of milk feeds per day over the last three weeks will increase solid feed intake. This will result in a smoother transition onto solid feed reducing the risk of a growth check during this period.

5. Water: clean fresh water is essential from day three, even during the milk feeding period; milk is a feed not a drink.

Find out more about how to set a growth rate for your heifers and how to achieve 24 months AFC in our Farmers Guide – Growth Rate Targets and Farmers Guide – Age at First Calving.


Milk Feeding for calves

Defining Mixing rates IN ORDER to meet CALF growth targets and rumen development



Have you have set your heifers’ target age and weight at first calving?

Take a calf with a 40kg birth weight, if your target age at first calving is 24 months with an accompanying 560kg body weight, then she will have to gain 320kg over 395 days to ensure she hits optimum breeding weight at 13 months. That means she must achieve an average daily liveweight gain (DLG) of 0.8kg throughout the pre-service rearing period.

Simple? Straight forward? To support this level of growth, then you need to make sure that you are providing your heifer calves with sufficient nutrition, both energy and protein. Also remember that during the milk feeding phase the calf’s feed conversion efficiency is at its highest.

One of our latest trials focused on feeding calf milk replacer to Holstein heifers at a rate of 900g per day. These heifers initially weighed 38kg and achieved a DLG of 0.78kg to 11 weeks – that’s around the level of growth required to reach the target we set above.

Defining mixing rates

To feed 900g of milk replacer per calf per day it’s important to check and review mixing rates to ensure that the milk is fed at the correct volume and concentration. For example you can either mix

• six litres per day at 150g per litre OR
• seven litres at 125g per litre

To find out more about various mixing rate levels please download our Calf Products Guide. 

If you are targeting high growth rates, then this will also increase your heifers’ energy requirements.  Energy intakes can be improved in various ways but increasing the milk replacer’s oil content from 16% to 20% has a negligible effect compared with simply feeding more of the same. Check out the various combinations in the following table.

Daily energy intake and effect of feeding a low vs high oil milk replacer, or different volumes or concentrations
Energy supplied/calf/day (MJ) 16% oil,    22% protein 20% oil,     22% protein
4 litres – 12.5% 7.5 7.8
4 litres – 15% 11.2 11.7
5 litres – 12.5% 11.7 12.2

Remember your heifers have a large ability to grow during the milk feeding stage. Review their quantity of feed, as well as the quality.


Six steps to correct mixing

FFG-Nutrition - How to mix milk

1. Accurately weigh the milk powder on scales
2. Use 125g of powder to 875ml water to make up one litre of mixed milk with a 12.5% solids concentration; using a full litre of water will lead to a weaker (11.1%) milk concentration
3. Take half the water (below 45°C) and add all the powder
4. Whisk until smooth
5. Add the rest of the water and whisk again
6. Check temperature (between 37-39°C) and feed

Protect your Calves against the cold this winter using our Calf Jackets Protocol

In the winter months, when temperatures fall, extra attention is Needed to protect calves from the effects of the cold, especially calves under 3 weeks of age.

calf jackets

Calf jackets help to keep calves warm, dry and healthy, in the winter when temperatures fall below 15°C. In colder conditions more energy is used to keep warm and therefore less energy is used on growth, development and supporting a strong immune function. Calf jackets do not replace good husbandry – they are an added benefit.

FFG-Environment-Thermal neutral zone

In our new Calf Jackets protocol farmer guide, we highlight areas which are important to consider when purchasing calf jackets and tips on developing your own calf jacket protocol in order to get the full benefit from using jackets

Calf jackets should be used in combination with good management practises such as providing the calves with a draft free environment, deep dry bedding helping the calf to maintain growth and support a strong immune function, reducing the risk of setbacks in calf health during periods of cold weather.

There are some things to be aware of when purchasing calf jackets. The jackets themselves must:

  • Have breathable material
  • Be water resistant or waterproof
  • Be machine washable.
  • Have adjustable straps and fasteners with low maintenance.

Once you have decided to use calf jackets, it is very important to use them properly to maximise their potential. A calf jacket protocol should be set to inform everyone working on the farm what is expected and what should be done. Jamie Robertson has helped us create a new Farmer Guide calf jackets protocols which you can download here. 

The Feed for Growth programme focuses on 3 key areas – Health, Nutrition and Environment. We have a range of Farmer Guides available to help you, covering everything from dealing with common health problems to feeding and housing your calves.

New born calves – meeting their nutrient requirements

Are you facing thE Dilemma of feeding whole milk or Calf milk Replacer?


Whichever you decide, remember the calf’s physiology dictates that for the first three weeks of life, she will be almost entirely dependent on liquid milk feed to supply the nutrients she needs to support health and growth.

Let’s take a look at pros and cons of both Whole Milk and Calf Milk Replacers.

1. Whole milk

The pros

  • Contains a high level of energy – 30% to 32% fat which is highly digestible
  • Provides a high level of protein (amino acids), 26% – 27% protein

The cons

  • Can transmit bacteria which infect the calf, including Johne’s, Salmonella, E.Coli
  • Can vary in nature which can lead to calf performance / health issues
  • Can result in delayed intake of solid feed, which can delay the age of successful weaning or result in post-weaning growth checks


2. High quality calf milk replacers

The pros

  • The proportion of energy supplied by the fat and lactose combined is similar to whole milk, despite the fact replacers contain 16% to 20% fat
  • Contain a blend of fat sources which are designed to be well digested
  • Lower fat, higher lactose – stimulates earlier intake of solid feed which encourages earlier rumen development both before and after weaning
  • Formulated to provide a consistent supply of energy, protein, vitamins and trace elements to meet requirements
  • Biosecurity – made using pasteurised milk
  • Convenient and easy to use, and always available

The cons

  • Have to be purchased

Calves have a requirement for protein, a minimum of 20% in the diet, but they also require specific amino acids – the building blocks of protein. The total quantity and balance of amino acids, not crude protein %, is key to muscle development and calf growth, but only the protein % is declared on the product label so it is impossible to judge likely animal performance from reading the label alone.

Five ‘must haves’ when purchasing a milk replacer

  • Minimum of 20% protein declared
  • Maximum of 9% ash declared
  • Minimum 0.8% calcium
  • A trusted supplier
  • Previous calf performance and calf bloom give the best guarantee for the milk replacer’s quality

If you decide to use a Calf Milk Replacer you must ensure the milk is mixed correctly.

Visit our website for the latest information and a range of downloadable resources, including our Farmers Guide to Mixing Milk to ensure you make the most out of your investment if you decide to use a Calf Milk Replacer.


Calf rearing systems – a guide

Have you reviewed your calf rearing system in the last couple of years? We suggest you do this regularly, ideally every year, simply because great investments have been made in cattle genetics during the last decade, and yet calf feeding and management practices have lagged behind somewhat, which may in turn be preventing animals from achieving their true genetic potential.

You have an array of calf rearing systems to choose from – individual pens or hutches fed by buckets, or groups fed by machines. It’s a case of selecting the calf rearing system which fits your own bespoke action plan for your farm.

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1. Individual pens or hutches: for example, buckets, buckets with teats.

The pros

  • Calves get individual attention and feeding.
  • Feeding can be controlled very precisely with measured amounts given in one or more daily feeds. Problems are evident if milk feeds are not taken.
  • Exposure to infections, particularly those causing scours, are reduced as mixing is minimal.

The cons

  • Individual pens are very labour intensive and require a large area for relatively small numbers of calves.
  • Socialisation of calves is limited.
  • Calf exercise is also limited.

2. Group rearing: for example, Milkbar, ad-lib systems

The pros

  • Calves can either be fed in troughs, Milkbar or an ad-lib machine, often following on from individual pens.
  • Ad-lib is more like natural feeding, whereas trough will still be done twice a day
  • Calves can socialise more easily and exercise more freely.

The cons

  • Infection spread is easier in larger groups, particularly scours and pneumonias.
  • It can be harder to check individual calves are taking the correct amount of.
  • If calves do become ill, they should be separated during any treatment which then requires individual penning.
  • Feeding machines need to be kept very clean to limit spread of infection between calves, and ensure the tubes don’t get blocked.
  • Ad-lib systems pose difficulties in controlling amounts of milk taken by calves because they feed as often as they like. Too much milk can make weaning harder since it can be difficult to reduce milk intake and encourage concentrate feeding.

3. Group Rearing (programmed feeding): for example, computerised feeders

The pros

  • Far less labour intensive.
  • Calves can socialise more easily and exercise more freely.
  • Calf collars or tags with microchips identify calves individually and control feeding levels precisely. The systems prevent overfeeding – the machine stops delivering milk to calves that have already had their programmed daily ration of milk.
  • Computerised feeding systems identify calves that don’t take in their daily amount and alert the stockman to investigate that particular calf.
  • Computerised feeding systems can deliver all the benefits of machine feeding with some of the individual management benefits of an individual rearing system.

The cons

  • Infection spread is easier in larger groups, particularly scour and pneumonia.
  • The feeding machine needs to be kept very clean to limit spread of infection between calves, and ensure the tubes don’t get blocked.

Visit our website for the latest information and a range of downloadable resources, including our Calf Rearing Principles which covers key areas such as colostrum, hygiene, mixing milk and our mixing rates calculator.

You can also visit our dedicated Youtube channel for useful tips and videos, whichever calf rearing system you decide to use.

Cold weather – are your calves at risk?



Young calves are very susceptible to low temperatures. They are on highly digestible feed and are not yet ruminating so less heat is generated by digestion.

During their first week of life and when temperatures plummet to less than 15°C, they’ll start using energy from feed to keep warm. High risk calves – those with a difficult birth and twins, will feel cold at higher temperatures.

By their fourth week, they’ll be more robust and won’t feel the cold until about 0°C. However, high moisture levels and draughts will dramatically increase their susceptibility to cold stress. Draughts of just 5mph will make calves feel 8-10°C colder.


Cold stress and its impact

  • Energy is diverted from growth to maintaining body temperature
  • Growth rates will fall and calves will become more susceptible to disease

How to prevent COLD STRESS

Have a plan for when cold stress is likely to happen, that’s when the ambient temperature drops below 15°C, or at a higher temperature for high-risk calves.

1. CALF Feeding

  • Make sure every calf receives adequate quality colostrum
  • Step up energy intake; this can be done by increasing the amount of milk offered per day, see table 1. Increasing the oil content of the milk replacer from 16% to 20% has a negligible effect on daily energy intake

Table 1: Increase in energy supplied by increasing calf milk powder oil content or feed rate


  • Increase the level of milk solids by 100g per day for every 10°C temperature drop below 20°C to maintain growth rates. See figure 1.

Fig 1: Additional calf milk replacer required to maintain growth rates in cold weather, for a calf aged 0 to three weeks or older than three weeks of age:


2. General housing considerations

  • Reduce cold drafts whilst maintaining adequate ventilation. Provide effective barriers to drafts at calf-level and places for the calves to shelter – plastic and timber are better insulating materials than concrete and steel
  • Put in place a system to drain moisture
  • Ensure bedding is kept clean and dry and provide plenty of deep straw bedding; it provides them with a great deal of insulation and reduces body heat loss
  • Keep bedding dry and clean – much of the insulation value of bedding is lost when it is wet

3. Specific intervention measures

  • Provide calf jackets
  • Provide an external heat source close to calves

Finally, calves born on very cold days take longer to stand and suckle so they may not receive enough colostrum to ensure adequate transfer of immunity. Make sure they each receive a minimum three litres or six pints within three hours of birth – use a teated bottle or stomach tube.

Grow better cows with our calf rearing principles

The Feed for Growth programme recognises that the first 3 months are a critical phase in determining a newborn calf’s adult performance.

In our calf rearing principles document, we highlight areas, which are important to achieve more efficient calf rearing. It covers five key areas; colostrum, hygiene, milk replacer, mixing rates calculator and weaning.


Key principles of calf rearing

  • Colostrum

To boost calf health and performance it is essential to feed the right amount of top quality colostrum at the right time. Our top tips are:

colostrum checklist

  • Hygiene

Improper hygiene increases the risk of disease and can be extremely costly.

Biofilms release bacteria and can contaminate the milk every time the equipment is used. Our calf rearing principles teach you how to ensure equipment is washed correctly which is essential to reduce calf exposure to biofilms.

  • Milk Replacer

A top quality milk replacer gives your calves the best start in life. Find out how to mix your milk correctly in order to get the most out of your investment.

mixing milk

  • Mixing Rates Calculator

Strategic feeding allows you to achieve specific growth targets which help eliminate waste and cost and thereby increase dairy profits.

Volac instant calf milk replacers can be fed at concentrations ranging from 10% to 20% dry matter, depending on the feeding system and growth rate required, but always mix at the chosen concentration consistently.

Our calf rearing principles provide a Mixing rates calculator to help you ensure you achieve your required growth rate.

  • Weaning

Correct weaning is essential to a calf’s future development.

Our calf rearing principles give you our top tips, checklist for weaning and other key information.

We advise weaning should be done gradually by reducing milk fed over a 7-14 day period.


The first three months of a calf’s life are crucial; they help determine its future health, growth and performance. Our calf rearing principles can help you to ensure this critical phase is not overlooked.

The full guide is available to download here, alongside a range of other resources covering everything from dealing with common health problems to feeding and housing your calves.

To find out more about the Feed for Growth Programme click here or sign up to our e newsletter to stay up to date with the latest information.

Preparing for calving

WINTER calving is here – are you ready? On average, 14.5% of live-born heifers fail to even reach first calving – every calf born needs gold star attention from day 1 to help reduce these losses.


The ability of a calf to convert feed into growth rapidly falls from around 50-60% (i.e. 100g feed will give 50- 60g growth, assuming a healthy calf in a thermoneutral environment) during the milk feeding period to only 9% by 13 months of age. The pre-weaning period is therefore one of the best opportunities to maximise growth, starting with colostrum.


Colostrum not only helps to protect the young calf against disease, but it is also important for calf growth and development. Furthermore, recent findings suggest that colostrum could help to improve the digestibility of subsequent milk feeds. Colostrum quality should be checked using a colostrometer – remember, a much higher volume of poor quality colostrum will have to be fed to offer the same level of disease protection as a smaller quantity of good quality colostrum. A good level of cleanliness and hygiene is vital – bacteria can double every 20 minutes if colostrum is left at room temperature.

A calf uses nutrients to maintain vital body functions (digestion, temperature, respiration) and only those nutrients in excess are used for growth. Calves must be fed sufficient energy and protein to support the target growth rate – this depends on the total amount of milk powder and calf starter fed per calf per day. Remember – grams of feed IN will determine grams of growth OUT. If targeting 0.8 kg per day of growth – a calf will need at least 800g of milk powder per day plus ad-lib calf starter.

Choose the right milk replacer for your system – if feeding calves a higher amount of milk powder for increased growth, then milk replacers with a higher protein content (23% and above) combined with a lower fat content (20% and lower), will help promote lean tissue growth and limit body fat. Calf milk replacers vary enormously (type and quality of ingredients, level of protein, fat and ash) – which determine their digestibility in the young calf.

Always purchase a milk replacer from a trusted supplier – previous calf performance gives the best guarantee for the milk replacers quality.

Be prepared for calving: having agreed protocols in place for calving, colostrum management and the subsequent milk feeding period will help pay dividends in later life.