Every dairy has milk that can’t go into the bulk tank whether it’s from transition milk, milk with high somatic cell counts or milk from treated cows. While this milk is off-limits for sale, it still has value.
Feeding raw or waste milk to dairy calves is one way to stretch your resources and support calf growth. But like every strategy, it requires the right tools, knowledge and attention to calf health.
Why Feed Raw Milk to Dairy Calves?
Raw or non-saleable milk offers a cost-effective way to nourish calves, especially during the 4- to 8-week window when their nutrient needs are high and starter intake is still developing. This milk typically includes cows with mastitis, those under treatment or fresh cows in transition. Rather than dumping it, many producers use it in the calf barn.
Still, raw milk isn’t one-size-fits-all. Its nutrient levels and quality can vary, so some farms add a milk balancer to increase the protein content, often aiming for around 25%, to better match the nutrition of high-quality milk replacers. This helps support healthy growth, muscle development and immune function.
Many farms choose to feed waste milk only to calves that are at least four weeks old, when the gut barrier is more developed and the risk of pathogen transmission is lower. Limiting its use to older calves can help reduce health risks while still making use of this resource.
Economics of Feeding Waste Milk
Feeding waste milk can offer a big cost savings, especially if your farm regularly produces excess. On average, U.S. dairy farms generate between 5 and 22 pounds of non-saleable milk per calf, per day.(1) Rather than discarding it, using that milk in the calf barn avoids waste and reduces reliance on milk replacer.
Nutritionally, whole milk often outperforms traditional 20:20 milk replacers, offering more fat and protein. For example, raw milk can contain about 25.4% protein and 30.8% fat on a dry matter basis, compared to 18-20% each in milk replacer. (2) This difference can lead to faster average daily gains and healthier calves.
In one Minnesota study, calves fed pasteurized waste milk gained 1 pound per day on average, while those fed a 20:20 milk replacer gained 0.77 pounds. That additional growth can translate into earlier weaning and potentially better lifetime performance. A budget analysis estimated $34 per-calf savings at weaning when using pasteurized waste milk over milk replacer. (3)
That said, raw milk quality can fluctuate. Without regular testing, it’s difficult to know if protein and fat levels are meeting calves’ nutritional needs. On some days, extra supplementation may be necessary to maintain consistency and support proper growth.
Health Challenges of Feeding Raw Milk
Calves fed raw milk are at greater risk for disease exposure. Because their immune systems are still developing, even small amounts of harmful bacteria can lead to serious issues like scours, respiratory disease or failure to thrive.
Feeding milk from cows with mastitis presents another challenge. While many bacteria are broken down in the calf’s stomach or destroyed during pasteurization, some, like toxins from Staphylococcus aureus, can survive and cause problems, especially in very young calves. That’s why it’s generally advised not to feed mastitic milk to newborn calves and to avoid any milk that appears abnormal.
Another concern is antibiotic residues. Milk from cows under treatment may still contain traces of antibiotics, and pasteurization does not remove these residues. When calves are exposed to low levels of antibiotics through their milk, it may not cause an immediate problem but it can quietly increase the risk of antimicrobial resistance. Over time, this can make common treatments less effective and harder to rely on when calves do get sick.
There’s also a risk that antibiotic residues could carry over into meat if calves are later sold for beef, an important consideration with today’s strong calf market. Managing waste milk carefully helps protect calf health, food safety and profitability.
Overall, raw milk can be a useful tool, but it comes with real risks if not managed carefully.
Pros
Helps reduce feed costs by utilizing a by-product
Provides higher levels of protein and fat compared to basic milk replacers
Can lead to faster weight gain and improved average daily gain
Supports better overall calf health when managed properly
Offers a sustainable solution to milk disposal challenges
Cons
High risk of disease if raw milk is not pasteurized
Nutrient content varies day-to-day
Requires investment in pasteurization and storage equipment
Time-intensive to manage and monitor milk quality
Potential for antibiotic residue if protocols aren’t followed
Should Raw Milk Be Pasteurized for Calves?
Pasteurizing raw milk is one of the most important steps a farm can take to protect calf health. Raw milk can carry bacteria like Salmonella, Mycoplasma, E. coli and even the agent that causes Johne’s disease. These pathogens can originate from an infected udder or be introduced through contaminated equipment or manure.
Pasteurization dramatically lowers this risk by reducing bacterial counts by up to 99%. A study referenced by Bovine Alliance on Management and Nutrition (BAMN) showed bacterial loads in raw milk ranged from 6,000 to over 1 billion colony-forming units per milliliter, depending on the farm. Pasteurized milk, by comparison, was consistently cleaner with some samples had as few as 2,000 cfu/mL.(4)
Pasteurization isn’t a one-step fix. You need a reliable system, proper storage tanks and a protocol to prevent recontamination after pasteurizing. If your setup falls short, pasteurized milk can end up being just as risky as feeding it raw.
Incorrect temperatures, dirty equipment or poor hygiene during storage can cause the milk to become re-contaminated. When that happens, bacteria levels can climb right back up, making the milk just as risky as feeding it raw. Without proper management, you lose the very benefits of pasteurization.
Real-World Challenges of Feeding Raw Milk and Dairy Producer Feedback
We’ve had the opportunity to discuss this idea with several dairy producers, and the consensus was pretty much unanimous:
Calves probably grow better on waste milk
Even supplementing with some saleable milk still made economic sense compared to milk replacer
The overwhelming reason not to feed waste milk was the management burden
Feeding waste milk involves serious infrastructure and labor:
Pasteurization is essential to reduce health risks
A separate tank is needed to collect and cool the milk
Transporting milk to calf housing adds time and complexity
Hoses, pumps and tanks all need to be cleaned thoroughly twice a day
Bottom line: While feeding waste milk can be economically viable and calves often perform well, the high level of labor, equipment and logistical coordination makes it unfeasible for many operations. Even those who’ve tried it sometimes revert back to replacer simply due to the hassle.
Stand Strong for Calf Health and Performance
Feeding raw or waste milk can be a smart economical decision for a dairy, but only with the right management. It offers real performance potential and cost savings, but the logistics, labor and sanitation requirements can be difficult to sustain. For many producers, these barriers make implementation just out of reach, even when the economics and calf growth are promising.
That’s where the right tools can help. Stand Strong™ for Dairy Calves is a natural, effective milk additive designed to support calves when nutrient levels in raw milk or milk replacer fall short. It’s a simple, reliable way to give calves the extra support they need, especially when milk quality varies day to day. Just mix it in and keep your program strong, no matter what you’re feeding.
Questions about feeding raw milk? Give our dairy specialists a call at 507-337-6916 or email RuminantHelp@RalcoAgriculture.com
Stand Strong for Dairy Calves – Milk Additive
Stand Strong for Dairy Calves is a natural milk additive that supports appetite and eases the transition to a grain diet while helping immunity.
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