Research is confirming some age-old calf-rearing wisdom, and encouraging new thinking on other aspects of ensuring calves’ optimum start to life.
Inside Dairy
6 min read
Science shows that giving calves early access to high-quality care and increased milk allowance pays off in growth, health and future performance.
Giving calves the best possible start to life has been shown to boost growth and resilience. There’s also emerging evidence that access to more milk from the very start can improve first-lactation performance. Scientists are still exploring exactly why this happens, but it’s thought that early nutrition helps calves’ mammary development and sets up their metabolism for stronger growth later.
Farmers tend to adapt calf-rearing practices to what best suits their operation, but there are some fundamentals many prioritise to establish the foundations of healthy, productive animals, DairyNZ’s senior animal care specialist Penny Timmer-Arends explains. “We know farmers take great pride in their livestock and strive to do the right thing,” says Penny.
Doing the fundamentals well sets the animals up for good future productivity.
“Every farm will do things slightly differently to rear good calves depending on their people, shed set-up and equipment, and every calf-rearer has some key things that are really important to them.
“Doing the fundamentals well sets the animals up for good future productivity.”
Some principles haven’t changed, like having draught-free sheds and dry bedding to keep calves warm. Others have come to light more recently, including the importance of good colostrum management.
“Early colostrum is so important for calves to get the passive transfer of antibodies, which helps them respond to disease challenges until their own immune system is up and running,” Penny says.
“The cow’s very first milk is rich in antibodies, and it’s so important to get it into the calf within about 12 hours to get the passive transfer of immunity.”
This is the highest quality colostrum and should be fed to newborns, but quality can vary. Brix refractometers can be used to measure the antibody level in colostrum. Gold colostrum that measures 22% or more is considered high quality. For the best results, the highest quality colostrum you have available should be fed to newborns.
Science shows that giving calves more milk early boosts growth and resilience, with benefits that can carry through to later performance.
“There’s emerging evidence that by feeding more frequently, it’s better for the wellbeing of calves and can impact future productivity over an animal’s lifetime,” Penny explains.
The link between higher weight gain before weaning and more milk in the first lactation is well proven in overseas systems. There’s been less research in New Zealand, but a seven-year trial led by the Bioeconomy Science Institute (formerly AgResearch) has found similar results. Scientists are still working to fully understand why, but early nutrition is thought to switch on mammary development and body tissue metabolism, leading to greater milk production in heifers.
Updated DairyNZ calf-rearing resources will be available this winter, reflecting the latest research and offering independent guidance on housing, health, colostrum, feeding and weaning – helping farmers put science into practice and give calves the best possible start.
“We took a farmer-centred approach to developing these, including interviews to understand what farmers and rural professionals wanted. We also went back to farmers to test early drafts of the resources,” says DairyNZ senior design specialist Kat Kevey, who led the development of the new suite of resources. A Canterbury-based farmer herself, Kat is no stranger to rearing calves.
At the heart of the resources is a comprehensive manual covering the foundations of calf rearing. It’s underpinned by the latest science and balanced with practical know-how from farmers.
“Experienced calf rearers also told us they wanted something to help new team members, so we’ve created a poster showing the signs of a healthy calf that can go up in the calf shed,” Kat explains.
One barrier to feeding calves more milk, more often, is time during the busiest period on-farm. Fitting in a second feeding around milking, pasture management, springer checks, and off-farm commitments can be challenging.
“Farmers I spoke to were open to change but couldn’t find New Zealand guidance on how to adopt ad lib feeding.
DairyNZ has now developed an ad lib feeding guide, informed by farmer experience, so we know it will work in our systems.”
The release of the resources will be supported by on-farm events over the dry period.
Find out more at dairynz.co.nz/calves
It’s all hands on deck at this Canterbury farm as the crew race to get colostrum into calves as quickly as possible. The payoff is in excellent calf health.
Cara Minson feeds calves twice a day for their first two weeks, then switches to once daily. The busy mum of two has a strong track record in calf health, which she attributes largely to careful colostrum management.
“I don't tend to get sick calves, and put it down to making sure I've got really good quality gold and getting it into them as fast as possible,” Cara explains. “That’s so crucial because if you get that wrong, you get sick calves.”
To help with this, Cara uses a highly insulated 125-litre milk cart she calls ‘Wanda’ for storing and transporting colostrum.
“We don’t have to re-heat it because the tank keeps it relatively warm, and we use it within 18 hours. Any leftovers go to older calves.”
Strong colostrum management and frequent feeding help Canterbury farmer Cara Minson raise healthy calves.
Every calf gets two to three litres of colostrum as quickly as possible, with tube-feeding used if necessary.
“Feeding twice a day is full-on – we start at 6am and finish after 5pm – but it’s working for us because I don’t get sick calves, and feeding more often feels natural and important to me personally.”
Cara relies on a small team during this busy time.
“It’s very physical work. I look after the team, making sure they get breaks and days off – that’s really important.”
Students from nearby Lincoln University, a couple of full-time staff, and Cara’s daughters, aged 15 and 13, help when they can. Cara prioritises hiring people with animal experience wherever possible – it makes a real difference on-farm.
“We train everyone in the shed on how to get the first colostrum to the calves quickly and at the best quality. That includes cleaning teats before collection and testing with a refractometer to ensure top-quality milk.
“What we do seems to work without doing anything fancy. It’s just doing the basics right.”
Visit dairynz.co.nz/feeding-calves for more information and keep an eye out for new resources this winter.
Ad lib feeding lets calves have milk whenever they want, and it’s working well for this south Otago farmer and her youngsters.
Emma McLeod transitioned to ad lib feeding last year, letting calves access milk whenever they need it. She says it’s great for calf growth and health – and it makes life easier for her as a busy mum of three.
Emma made the feeders by recycling 200-litre drums from the cowsheds and adding teats.
“I chose the ad lib system because it’s so easy,” she says. “With three kids and morning feeds, the calves always have access to food. My friends who use it said it’s a game-changer, so I jumped on board too.”
Each morning, she does a quick check and tops up the drums if needed. Once the kids are at school, she washes out and refills the containers with a 24-hour milk allocation, checking calves’ condition and making sure everyone’s fed. Key signs she looks for are perky ears, bright eyes, a shiny coat, and a full tummy.
Emma McLeod says ad lib feeding keeps calves calmer, healthier and growing well on her South Otago farm.
“If they’ve drunk it all, I just give them a bit more,” Emma says. “The point is to get them drinking as much as possible in those early days when we’ve got lots of transition milk.”
She hasn’t seen any drop in meal uptake, and reports healthier, more settled calves growing faster.
“It’s calmer and more relaxed. When I arrive at the shed, they’re not hungry, so I can focus on the new calves and giving them the gold colostrum.”
Ensuring every calf gets the best colostrum quickly is Emma’s top priority. She tests levels carefully, feeding only milk with a Brix rating over 25.
“I make sure their first two feeds are gold, and they can drink as much as they like. I prefer not to tube-feed, but I get them to stand to take their first drink until they’re full. I reckon you can see later if a calf hasn’t had gold – it shows in growth rates and health at weaning.”
For anyone thinking about ad lib feeding, Emma’s advice is simple: “Just do it! The benefits are there for the calves and for us, so why not adopt it?”
Kat Kevy - DairyNZ senior design specialist
This article was originally published in Inside Dairy May-July 2026.
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