A Calf-Rearing Masterclass

The rewards for good preparation leading into calf rearing won’t just be felt this spring, they’ll go on for years as well-grown heifers become productive, long-time members of the herd.

March 26, 2024In Livestock18 Minutes

Calves sold to rearers will be more likely to grow faster and that will bring repeat customers for your stock and perhaps even a premium. Karen Fraser and Stacey Cosnett from The Calf Experts say now is the ideal time to review your calf rearing system – noting what works well and what needs improving.

Minimising stress and fatigue for both animals and people is key. “The link between stress and distress emphasises the need for proactive measures,” Karen  says. Young calves will face a number of stresses in their first day of life that aren’t in themselves harmful, but care needs to be used to minimise the stress response from the young animal. Separation from the dam, transport to the calf sheds with noise and vibration, temperature changes and unfamiliar surroundings, handling and feeding are all potential stress points.

Any abrupt changes to diet such as changing from whole milk to calf milk replacer (CMR) or proceeding too quickly with the weaning process also create stress on the animal’s digestive system. All of these stressors can weaken the immune system, disrupt digestion, decrease weight-gain and make calves more susceptible to diseases and parasites. Along with the stress produced by dealing with sick or poor performing calves, poor facilities and systems and under-staffing can create stress on the rearer too. “A rearer under stress is going to find it a lot harder to take the care they need to,” says Stacey. “They’ll be less observant and slow to react to problems and before you know it things start to spiral.”

Review, Organise & Plan

Set up the systems to ensure top quality colostrum, make sure any purchased nutrition inputs are of a good quality, and that housing is well set up so calves can be fed in a low stress way for animals and rearers.

Make sure you have all your equipment at hand including a rectal thermometer for checking calf temperatures, tools such as refractometers or colostrometers for testing colostrum quality and very importantly good quality electrolytes.

Avoid hesitation

Swift identification of animals that aren’t doing well and then acting on that can save lives and mean a swift recovery for young animals. Be on the lookout for the early signs such as calves that are slow to rise or are keeping to themselves. “Watch them when they’re feeding, look to see they’re actually drinking and not standing there blowing bubbles,” Karen says.

That drop in appetite can be the first sign something isn’t right, Stacey says, and electrolytes should be the first port of call. “If people act early, separate the slow drinking calf off and give them electrolytes, it’s amazing how quickly they can come round.”

“It’s about observation and using multiple senses – the smell of ammonia in the sheds, calves that aren’t interested in feeding or showing lethargy – trust your gut,” Karen says.

As well as monitoring animals, you should be monitoring environmental conditions such as bedding quality, ensuring no damp or wet areas and that calves are dry and well ventilated.


One of the tricky areas of reviewing your system to ready yourself for the new season is to recognise when the abnormal has become your normal, Karen says. When people lack awareness or training, they may accept suboptimal conditions as normal. If they don’t have a benchmark or an example of what good looks like they can just accept that what’s happening in their system is ok.

“Go back on your records and ask yourself if your past growth rates are optimal. Be honest about it and think about whether you’re just accepting a standard because that’s what you’ve always done,” Stacey says.

It’s important to upskill the whole team and bring in advice and get out to expert workshops. “It’s important that everyone gets training – from the casual person to the senior team members and managers as well as the staff who are handling the colostrum and picking up the calves in the paddock,” says Karen. “It’s not just about what’s going on in the calf rearing shed.”

“It’s important the farm staff understand that cow condition, winter feeding, feeding springers and transition feeding affect the unborn calf, its immunity levels and cow colostrum quality too. It’s that holistic approach that will bring the whole system’s standards up,” Stacey says.

“There’s a lot about this that involves good leadership – upskilling people and also empowering them so they can act to problem solve themselves, so that they have confidence and passion about what they’re doing.” she continues.

Simple & Consistent Systems

“When it gets over-complicated – that’s when people start reaching for what I call ‘feel-good’ products that may in fact be unnecessary and even detrimental if not used correctly,” Karen says. “Some will reach for binder type products at the first sign of calves looking off-colour in hope of heading off scours and some will overuse them.

“What a sad or scouring calf really needs in that moment is rehydration and some energy, and fast! An electrolyte should be the first port of call,” Karen says. “They’ll then throw the kitchen sink at them – antibiotics, anti-inflammatories, extra probiotics – when often it’s electrolytes they really need first and foremost, but we often miss the first signals or ignore the first stress points. There are definitely times when you need to act and use antibiotics and treatments but knowing when to do that is important.”

Preparing well and having good nutrition – good quality calf pellets, good quality CMR or whole milk with the right programmes that fit your own breeds, farm, and environment will help calves grow well and be more robust in terms of immunity.

When comparing calf pellets for instance don’t let price be the deciding factor. Take a look at the ingredients list – in particular the starch and protein levels, the vitamin and mineral range including B vitamins and beware of fillers such as high levels of palm kernel expeller (PKE) or copra, Stacey says.

Also look at fat levels – high levels of unsaturated fats in a calf meal are not ideal. A coccidiostat should be included too.  “Always look for the FeedSafe tick which is a New Zealand standard that’s audited,” Stacey says.

Recycled fish and chip oil, biscuit waste and other by-products can easily find their way into cheaper feeds and the accreditation process ensures animal feeds are the right quality and the manufacturing processes are a good standard, Karen says.

Managing changes in diet is important so that any transition is carried out over several days and ideally over two to three weeks when it comes to weaning. “You’re wanting to get to weaning and have calves with well-developed rumens that are able to graze well and get the most from that grass. Calves with poorly developed rumens will suffer at weaning and can go backwards rapidly,” says Karen. “Early intake of a good quality calf pellet will set your calves up for a successful weaning.”

A little time and effort improving sheds before the season helps to eliminate issues from the previous seasons and makes calf rearing more enjoyable and less stressful. More profitable too, as better sheds will mean less illness and fewer losses.

Prepare well for colostrum gold

Colostrum management is one of the most important things to get right because it sets calves up with great immune systems that will have a positive impact on productivity and performance for their entire lives. Hygiene in a dairy is the most common culprit of early calf problems.

Have as many tube feeders/teat feeders as you expect newborn calves on a busy day. This way you know each new calf will be fed with a clean feeder. Sharing the same teat on a teaser bottle is not the best idea.

Calf Experts’ 5 Qs of Colostrum


  • Fresh is best! Calves born that day should get the freshly harvested, first milking gold colostrum – avoid mixing poorer quality colostrum with high quality.
  • IgG (immunoglobulin) content should be measured using a calibrated refractometer, a minimum reading of 22 brix is classed as good quality colostrum.
  • Don’t let colostrum sit, either feed, pasteurise or immediately refrigerate or freeze. Left at room temperature allows bacteria to double every 20 minutes.
  • Freeze any left-over, great quality, colostrum in 2l amounts to keep for the days when quality is not ideal.


  • Calves need 10% of birth weight in colostrum on day one. For example a 40kg calve will need 4l. A higher volume will be needed if colostrum is of a poorer quality – up to 15% of birth weight.
  • For the first feed let the calf drink its fill. If possible, offer a second feeding that same day.


  • The goal is to get colostrum into calves within the first 1-2 hours of birth, or at least within the first 6-12 hours to make the most of the golden window of opportunity when the gut is best at absorbing IgG’s. After 24-hours this ability is greatly decreased, however, colostrum is still useful as it lines the gut and protects it, so keep feeding colostrum for as long as the “free” supply is available.

sQueaky Clean

  • Avoid bacterial contamination. Keep all day-one buckets clean and covered. Avoid bacterial contamination including mixing leftover colostrum from the previous day or heat damaged colostrum. Bad bacteria can be passed into the bloodstream and can limit a passive transfer.
  • Keep all freshly harvested colostrum covered, avoid faecal splashes in the dairy shed.


  • A stressed calf will not absorb IgG across the gut wall as optimally as a calm calf. Handle calves quietly and gently from pick-up to feeding. Rough handling or stressed calves will impact on the passive transfer.
  • Calves with failure of passive transfer will always be on the back foot and are forced to divert nutrients from growth to mounting an immune response.
Karen Fraser.
Stacey Cosnett.


Calf sheds

Calf shed space has been coming under increasing pressure with tight calving spreads and farmers rearing more calves longer for dairy beef options as they aim to reduce bobby calf numbers. Having adequate facilities though is a key success factor so plenty of thought needs to go into how set-ups can be expanded and what other sheds might be available on the farm.

Putting time into understanding how the system will work if the operation is spread over more buildings can prevent stress particularly during the peak rearing weeks. Karen Fraser says the logistics of moving milk, whether there’s enough feeders and water troughs as well as other gear needs to be considered. “Overloading of sheds can put overwhelming pressure onto sheds, people and of course the calves,” she says.

If it’s a distance away from the current set-up then the logistics are even more critical.

So too is the quality of the facility itself. “Is it dry, is the foundation and base adequate for bedding to go onto, do you need to let natural sunlight into the shed, is it ventilated above head height but not draughty at calf height?

“Good drainage is important. Poor foundations will cause moisture to build up in pens. A wet and shivering calf is very vulnerable and opens the door for illness as bad bugs thrive in moist environments,” she says.

A little time and effort improving sheds before the season helps to eliminate issues from the previous seasons and makes calf rearing more enjoyable and less stressful. “More profitable too, as better sheds will mean less illness and fewer losses. Once we load our sheds to full capacity without making any changes, then as the shed fails under the pressure everything starts to fail including the rearers.

“The calf environment is a basic you must get right if you want to set yourself up for success. The quote ‘insanity is doing the same thing over and over and expecting different results’ seems very relevant here. It’s important to reflect on issues and improve things if we want better outcomes.”

For those moving farms, it’s important to do a thorough check of the calf rearing facilities as soon as you get onto the new farm and make any improvements early.

Find out from previous calf rearers or operators what works and what needs fixing or how it could be improved rather than finding out in the thick of your first season.

Work out if the numbers you intend to put into a shed will put too much pressure on. “The rule of thumb is 1.5 square metres per calf. Shed pens should be twice as deep as they are wide.

“On your first intake you can fill to capacity, but next round of calves do a deep fresh bedding top up and put 20% fewer calves into that shed. Repeat as needed. If you can’t house half the calves being born on the farm for the first three weeks, then you may need to think about increasing infrastructure.”