Risk Category 6
This is part of an 11 category program to help farmers learn to identify and manage the unique risks on their farm. This may help them to grow a food safety mindset, that may enable them to write their own food safety plans for the production of raw drinking milk. In Australia raw milk from cows for human consumption, is only allowed if you own the animal, but that doesn't stop farmers from becoming acquainted with practises that are delivery great results overseas. Farmers may need to read the introduction first before continuing on this page: Introduction to the Risk Identification and Risk Reduction Program
The development of a balanced rumen
According to this Australian article, it is common knowledge that calves are born without any immunity. "They acquire immunity as neonates from antibodies in colostrum (passive immunity) and then they develop immunity through exposure to different pathogens as they age. This is active immunity. If calves do not receive sufficient passive immunity, their ability to survive is severely compromised."
When a calf is born, it is dependent on its mother for the right kind of nourishment for a good start in life. While it is drinking from its mother, the rumen does not develop quickly. The microbes in their rumen start to take hold once the calf begins to eat fibre because microbes require fibre to establish themselves. British raw dairy farmer Christine Page describes in this article that calves tend to drink too much milk when left on their mothers too long, because the mother naturally produces more than the calf needs. Care needs to be taken not to over-feed a calf, which can cause scours (diarrhea), loose stools and dehydration. It is a good risk reduction strategy to encourage the calf to start
eating fibre (grass and hay) sooner rather than later, because it can have a potential knock-on impact of long-term, impaired rumen function as an adult. Christine writes that the calf’s rumen begins to fire on all cylinders (if not yet at full throttle) after 3 months. The calf is then incentivised to eat even more fibre, which in turn further accelerates rumen development.
It can be considered a risk mitigating practice to allow calves to suckle on mother's milk for the first few weeks. The mother produces the antibodies in her colostrum the calf needs for protection against disease. Christine says it is also well documented that heifer calves who suckle on their own mother in the first 2 to 3 months have far greater growth rates and are taller than those fed conventional milk-replacer. It creates a more robust animal to join the milking herd in the future. There is also evidence to show that it is perhaps best to monitor what calves and young heifers in the RDM system eat because of the risks some conventional feeds can pose to rumen development.
Cow-Calf Dairying - satisfying consumer demand for ethical and humanely-raised dairy
There is tremendous interest in cow-calf dairying in Australia at the moment after articles like this one. Dairy farmers however are finding it very challenging to understand the dynamics and economics behind it, let alone how this works in a raw milk system. For this reason, this information is included.
Calf at Foot dairying is a perplexing and highly specialised form of dairying that can be hard for some dairy farmers to get their heads around, as described in this article. Three micro dairies in the United Kingdom who are in the public eye, seem to have perfected the fine art of balancing the emotional and physical needs of both cow and calf. They also show why there are no set rules, only guidelines. Each cow-calf dairy tends to have their own unique practises and values:
The Calf at Foot Dairy operated by Fiona Provan
Smiling Tree Farm operated by Christine Page
Ahimsa Dairy Foundation operated by Nicola Pazdzierska and Sanjay Tanna
This is not a new concept. People have kept a house cow and shared the milk between calf and humans for thousands of years. Nowadays milk from these dairies are the most expensive milk you can buy, but there is a market for it. The cows get to keep their calves and there is an emphasis on the animal's quality of life. They sometimes stay together as a herd of all ages.
Fiona Provan explains that it is important for her to keep the calf with its mother because it reduces the mother's stress levels and it shows compassion for mother and calf. She keeps the calves at foot (by mums side), and the mothers are milked just once a day for the dairy. Fiona admits that her setup is not going to make her rich in this article, but it makes her happy.
Farmer educator Christine Page has written a series of articles about Cow-calf dairying, looking at the practicalities of producing ethical, cruelty-free milk by allowing dairy cows to keep their calves. It covers why conventional dairy cows don’t keep their calves and why humanely-produced milk using cow-calf dairying is rare and costs much more to produce. In England with its farmer- and consumer-friendly raw milk regulations these dairies flourish. Some consumers are happy to
pay the hefty price tag for the calf-friendly milk because dairy preferences and personal values are met. It is important to emphasise that this kind of dairying can work well for some micro dairies. Time will tell if this can be done with a larger herd. Both Smiling Tree Farm and The Calf at Foot Dairy produce 100% grass-fed Pasture for Life raw milk.
Below is a video about Fiona Provan's Calf at Foot Dairy. She has set out to find a healthy symbiotic way of working with the animals, more here. Turn up the volume to listen:
Please remember that we are not dictating to farmers how they should farm. This is an exercise in identifying risks, and showing farmers how they can change their mindset to manage risks better. Some of the information shows examples of how sustainable improvements can be made the farm. There is always a choice. Many farmers are not in a position to do cow-calf dairying. Many consumers will not be interested in paying the hefty price tag for calf-friendly milk. Many consumers will be grateful for access to any high-quality raw drinking milk (RDM). We are not here to make farmers feel guilty. Animal health is the most critical factor in RDM production, so please do not criticise ARMM for emphasising precisely that.
The Vegan Wars and dairy
There is a growing portion of society who are very angry and disturbed by intense animal agriculture. In May 2018 SBS Dateline published a story about industrial-scale farms and how growth in the dairy industry is affecting the environment concerning pollution and ethics. In the story, Dr Michael Mosley was asked if he’d ever become a vegan, and raw dairy farmers from Fen Farm Dairy were interviewed about the online abuse and death threats they received earlier in March.
There are two things missing from the debate however. There is no mention of the difference between intense animal agriculture (often grain- based and confined) and regenerative humanely raised farming (often pasture-based and free to roam). The first food system is unsustainable and produces many ethical dilemmas. The second food system gives farmers and consumers a more ethical and nutrient-dense choice. There will be more harmony between farmers and consumers when they can have a direct relationship. Consumers are willing to pay for the kind of foods and farming practises of their choice. Many consumers want to be able to know, visit and influence their farmers to produce food
in a certain way. Farmers also benefit from the direct relationship because they can explain farming issues to consumers. We’ve also seen a lot of evidence that the Australian government only support large-scale farming and primarily export. It’s time Australian politicians take responsibility for policies that prevent Australian consumers from connecting directly to local food producers, for products like RDM.
It is also becoming clear that vegans in general tend to be very disconnected from farming. In America there are many ex-vegans who are now raw milk producers and many ex-vegan raw milk consumers... this is a very curious reality. It is possible that in being disconnected from farming methods that create nutrient-dense foods, these people were disconnected from nutrition. In this interview at the 31 minute time marker, raw milk producer Mark McAfee explains why the human brain requires good fats for nervous system tissues. He says that Schwann cells require insulation, and that after years of not having animal fats many vegans loose that insulation and become a nervous wreak. He says that within hours of consuming raw cream vegans settle in a calm and stop shaking.
Calf sensitivity to temperature extremes
Calves are vulnerable to extreme temperatures. According to veterinarian Dr. Catharina Berge in this article "a calf may need up to 50% more energy in cold weather conditions simply to maintain the core body temperature. However, the extra energy requirements are not used for weight gain and growth. The immune system furthermore require large quantities of energy, and if all energy is diverted to maintaining core temperature, it will lead to a suppressed immune system. The newborn calf has virtually no fat reserves, and a cold weather spell can quickly lead to hypothermia and death." She says the newborn calf desperately needs the energy and the immunity from colostrum. This is the special milk that the mother will produce for the first four days or so. She says most calves are not functional ruminators under two weeks of age, so they will get very little energy from grain. To reduce the stress of calves, they have to be protected from the elements and may need a heat room, infrared lamp or calf jacket to keep their body temperature steady, as risk reduction.
A shift in calf health and wellbeing is accelerated in raw milk systems
Dr. Cat Berge says she is happy to see that the calf is getting increased focus. She preaches the message "Healthy Heifers for Future Productivity" and has done a lot of research on calf management. In many countries, calves do not get enough colostrum or have basic needs met. She says most farmers around the world do not evaluate the performance of the heifers and it is not generally known if they are managed right for optimal growth and future productivity. Australia does seem to have more focus on heifer health than other countries (example) but there is room for improvement for the industrial dairy industry.
Opening the dialogue about the health of the calf is an important risk reduction strategy. We need the future milk producers to be in excellent health for RDM production, from as early as possible. Dr. Cat's research shows that calves can be big pathogen producers. More research is needed to see what can be done differently so that calves develop a healthy protective immune system and rumen as soon as possible.
In this article, Dr. Cat explores the idea that immunity begins before birth and how important it is to implement immunity sooner and stronger so they can fight off environmental exposures. High-stress situations lead to impaired immune responses. "Stress hormones interact with most aspects of the immune system and can dramatically depress calf immunity." When the calf's immune system is encouraged with a holistic approach, it will show improved performance throughout its lifetime. Blaine McAfee, who is the herd health manager at Organic Pastures Dairy developed organic treatment protocols for the cows and calves, read more here. If farmers are using strategies like these on the farm add them to the RAMP food safety plan to show how you are reducing risks effectively.
Cream O'Galloway's | The Ethical Dairy is a cow-calf friendly dairy that is now producing unpasteurised cheeses, while allowing the calves to stay with their mothers. According to this article farmer David Findlay said: "Our goal was to farm in a way that is resilient, ecologically sound and less stressful for the animals and the people working with them, so we're leaving the calves with their mothers to suckle. It means we take less milk from each cow but we're seeing real benefits from this approach - longer living, healthier cows, less antibiotic use, faster-growing calves and less purchased feed."
An earlier project that they trialled in 2012 cost them an awful lot financially, however they learnt a lot as well because the impact it made on cow contentment was staggering. All the animals were noticeably calmer, less aggressive and far more confident. See this video. We need more research like this to identify how many risks are being mitigated when the cows and calves are no longer stressed out due to separation. A natural contented life clearly contributes to animal health and better RDM. These animals have emotional needs that, when not met, may add to a lowered immune system and more pathogens in their system. These dairies show it is possible to manage how humans and calves share milk.
Colostrum quality given to calves crucial for calf health
There is evidence that calves are not getting sufficient passive immunity from colostrum due to commonplace industrial dairy practices. If calves do not receive sufficient passive immunity, their ability to survive is severely compromised. A study that was carried out on 24 dairy farms located in central Victoria showed that industrial dairy farmers do need to make some improvements when it comes to getting quality colostrum to calves. According to this article, in September 2016, the Journal of Dairy Science published the findings of a study of colostrum quality by a group of Victorian vets and scientists. The study investigated:
The colostrum storage and handling practices carried out on farm.
The immunoglobulin concentration and bacterial composition of colostrum being fed to replacement dairy heifer calves.
The percentage of colostrum being fed to replacement dairy heifer calves that meet industry recommendations.
The risk factors for bacterial contamination of colostrum.
The overall results of the study were no surprise to the article author Jeanette Fisher from Heifermax, and probably not to the researchers. Ten colostrum samples were collected from each farm; each farm harvested and stored first-milking colostrum using their normal colostrum-handling procedures. Please remember this study was done on farms who produce for the industrial dairy industry!
"Only 58 per cent of colostrum samples met the recommended industry standard of a total plate count (TPC) of less than 100,000 colony-forming units (cfu) per millilitre. This means that 42 per cent of the samples were so contaminated that they were potentially hazardous to calf health."
"Leaving colostrum sitting in a test bucket on the dairy floor because it is too hard to comply with best practice colostrum management recommendations will not stop that colostrum becoming contaminated to the extent that it is lethal for calves."
In her article, Jeanette wrote that it is necessary that calves receive their first colostrum as early as possible, preferably within the first two hours of life. She made many good recommendations for farmers in the industrial dairy industry, one being that management practices must be modified to accommodate the calves' natural biological processes. She acknowledged that society's views on what was considered ethically acceptable 50 years ago has changed, and that consumers have a powerful voice in promoting change for the better. The rise in the conscious consumer is already driving change in many other countries. Australia’s powerful dairy lobby is not immune to it.
Many farmers who produce for the RDM market have found a multitude of benefits in allowing the calf to suckle directly from its mother, and this can be seen as a risk reduction strategy as well. It is now not uncommon for some raw dairy farmers to produce RDM at Coliform counts of zero. The herd enjoy extreme good health and produce a great quality milk. There are many incentives to control the quality of milk harvested from the cow. The milk is frequently monitored (and tested) for infection in the four quarters of the udder. These strict quality controls in a regulated RDM system almost guarantees a high-quality colostrum, packed with antibodies tailor-made for the individual calf. What could be better for the calf than the colostrum directly from the mother cow?
Immunity is the defence of calves against pathogens (bacteria, virus, parasite or fungus). If it is not up to scratch, calves can be carriers and shedders of pathogens. This can be a risk to the raw dairy operation. If sick calves are kept in a pen their environment should be cleaned regularly. Soiled bedding should be removed and cleaned between groups of calves to avoid cross-contamination. There should be adequate ventilation, with protection from heat, cold, rain and draughts. Closed sheds are not ideal as ammonia and other fumes can accumulate and affect a calf with an already compromised immune system.
As risk reduction, sick animals can be separated from healthy ones and confined to a hospital pen or area.
Calf management in different operation sizes
Raw dairies around the world have different approaches to calf management. There is no one-size-fits-all approach. A micro dairy may do it very differently than a larger operation where risk reduction is more important for the continued operation of the dairy. In some of the larger operations, calves are separated from the milking herd, and it is seen as essential because of the risks they may pose.
Fortunately, there are other ways to manage calves with compassion. Some operations may employ nanny cows. Some cows have more mothering instincts than others and are happy to fulfil this role in the herd. Experience shows calves can happily adjust to other arrangements like this because they receive similar nurturing from what they can gain from a birth mother. It is possible to separate the milking herd, and still provide a nurturing environment for the calves with other foster caring mothers of the same species. Food safety first.
Not all cows show natural mothering instincts, and some will reject their calves. This is not uncommon. In these cases farmers have to be creative and find an alternative arrangement for the calves.
It is also worth mentioning that cows tend to go to a secluded area to calve. The mother and her newborn tend to stay separate for a day. The following day she may introduce her calf to the herd. The newborn is free to interact with the group and it is normal to see the spontaneous
organisation of a creche - where a nanny steps up to stay with the calves each day, while the mothers leave to forage. This natural herd behaviour provides a sense of security. The herd can enjoy a quality of life and emotional wellbeing from being allowed to live as close to their natural behaviour as possible. These moral and ethical considerations make dairy farming worth it for the welfare-oriented farmer as well.
How Now Dairy is an ethical, cow-calf dairy in Victoria, Australia with a herd of 42. In this interview, Cathy explains her experience with calves and confirms that they are happy to drink from any mother who will allow them to suckle. It is normal for a mother to leave her calf with a group of other mums and go out for a feed. Cathy says that her cows show no visible signs of stress because their calves are always close, even during milking. Please note that the law in Victoria currently require all farmers to pasteurise their milk before it goes up for sale for humans otherwise a bittering agent has to be included.
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Life’s tough! Afternoon snooze in the sun. With all the babies sleeping, the mums go off to eat... but they never leave the calves unattended. One mum stays back to watch over them. Such a clever well organised little bunch❤️❤️❤️❤️ hope your fridges are all stacked with How Now for morning coffee and the week ahead. #nomorebobbycalves #cowandcalftogether #family
Feeding grain, calf pellets and calf starters
Calf pellets are often fed to calves in the dairy industry as a feed supplement or concentrate. It seems to be acceptable practice in the industrial dairy industry but is it safe to assume that it is risk-free for the RDM operation? A quick Google search reveals that the top ingredients in these pellets tend to be cereal grains like wheat, barley, corn, sorghum, rice, soy bean etc. Calf starters seem to include many of the same cereal ingredients. There are concerns about these feeds for calves who will someday be producing for the RDM market.
Grains are often high in phytic acid which is the protective layer preventing seeds and grains from germinating until the conditions are right. It's a self-preservation method. This is also discussed in the Feed risk category. Phytic acid is not a problem for healthy adult cows, goats and sheep because phytase is an enzyme produced by rumen microorganisms that neutralise phytic acid and liberates the phosphorus. Calves, however, do not have developed microflora in the rumen, and may be vulnerable to consuming grain until the microbial balance in the rumen is established. Sally Fallon Morell from the Weston A. Price Foundation says that grains are full of anti-nutrients, like phytic acid, and have to be carefully prepared or else their chelating effect can cause serious health problems for humans who eat them. In her book Nourishing Traditions, she explains that if grains are not properly prepared, the phytic acid can combine with calcium, magnesium, copper, iron and especially zinc in the intestinal tract and block their absorption. Minerals are essential for animal health and growing resistance to bacterial infections. Phytates represents just one of many anti-nutrients present in grains and seeds. These include oxalates, tannins, trypsin inhibitors, enzyme inhibitors, lectins (hemagglutinins), protease inhibitors, gluten, alpha-amylase inhibitors and alkylresorcinols, more here.
In this article, Dr. Cat Berge explains that calves do not have a developed rumen and are therefore more susceptible to mycotoxins from mould that can grow in grass- and corn silage. Silage also seem to pose unacceptable health risks for the vulnerable calf.
Seeds like cottonseed are given to both beef and dairy cattle in industrial systems as a supplement in mixed feed during dry times. Cottonseed, however, has a natural toxin called gossypol. It is a natural toxin present in the cotton plant that protects it from insect damage. According to this article cattle cannot be allowed to eat too much of it, or for extended periods of time, due to toxicity that can cause heart failure and death. Toxicity has also been reported in young calves because they do not have a well-developed rumen. The natural protective systems of grains and seeds clearly pose various risks to the health of calves that farmers may not be aware of. Cottonseed is also another one of the many types of seed and grain that can be genetically modified and sprayed with agrochemicals.
It is said that a "large percentage" of grain growers in Australia illegally spray their grain crops with chemicals pre-harvest in Australia to serve as a desiccant. This is practical for farmers before wheat harvesting, however some of these chemicals can have antibiotic properties. Some experts say ingesting these chemically-sprayed foods and the low-level exposure to antibiotics can harm the microbiome of humans and are cumulative. They may have an impact on the rumen development of calves too, as both humans and cattle depend on an internal balance of beneficial microbes to stay healthy. Agrochemicals with antibiotic properties may slow down or disrupt the development of healthy microflora in vulnerable young calves. See this article for an in-depth exploration of this topic.
In a recent Wise Traditions podcast research microbiologist and expert on the human microbiome, explains the science behind the damage the agrochemical glyphosate causes to the human body's microbiome. Kiran Krishnan says that it disrupts the shikimate pathway of microbes and actually "selectively kills the good bacteria and allows for the growth of a significant amount of bad bacteria". He says it increases problematic pathogens like Clostridia, Klebsiella, Salmonella etc. Many scientists make similar statements like this that are alarming. There is concern about glyphosate’s ability to create pathogens in the terrain. This is an unacceptable risk for the raw milk dairy. We cannot take risks like these when it can be avoided. We have to identify this as a potential risk. It would be very irresponsible not to.
Feeding these pellets to calves who will one day be joining the milking herd may be a risk. Their use may be acceptable for systems where raw milk is produced to be pasteurised, but this does not automatically make them suitable for animals producing raw milk for a system that relies heavily on the health of the animals for the food safety of the end product.
This fascinating article by veterinarian Dr. Cat Berge, explores feed-associated hazards of mixed grain-based feeds. She says that pathogenic microbial contaminants, moulds and yeasts may all be present in the feed and detrimental for animal health, productivity and health, and ultimately for human health. These hazards may be introduced via feed ingredients or contaminated during the production, handling, storage or transportation. Many components, from various sources, are mixed together. Transparency, traceability and accountability can disappear. The article also explores some of the common tools to attempt to make the feed pathogen-free and toxin-free. There are many intervention strategies, chemical treatment strategies and additives to reduce the risk that feed may pose to rumen function, which may pose additional risks. Animals in industrial systems are now also given prebiotics and probiotics to prevent dysbiosis when supplied commercial grain-based feeds.
It is a good risk reduction strategy to be aware that these pellets, in general, can carry risks or may affect the health of young animals with an underdeveloped immune system and rumen. These were developed to be used in the industrial dairy industry, and we do not know if they are suitable for the RDM operation. This is an area of animal health that needs more research. For more information about feeds, see the risk category Feed.
The health of the calf, in general, should receive more priority...
Milk Replacer quality differences can vary significantly
Milk replacer is powdered milk formula fed occasionally or daily to calves in many industrial dairy operations. An investigation shows there are some risks involved, especially if a raw milk producer assume that this practice of the industrial dairy industry, can be carried to the RDM operation without problem. Milk replacer can consist of multiple ingredients sourced from different locations, and even different countries. It can be sold in plastic or paper bags making it vulnerable to contamination. There is the risk of rodents or spoilage during storage.
According to this CSIRO webpage milk replacers can be made up of ingredients such as skim milk powder, vegetable or animal fat, buttermilk powder, whey protein, soy lecithin and vitamin-mineral premix. The page says that milk replacers can contain antibiotics as an additive. As with calf pellets, milk replacer can also include a variety of other ingredients to keep it from spoiling, and to help the calf to tolerate the product better.
This article explains that not all milk replacers are equal. In other countries milk replacers can "contain bacteria counts of less than 20,000 colony-forming units (cfu)" or even more depending on whether it is human-edible grade or milk-replacer grade. The article also says: "These higher counts (<20,000 cfu) can compromise a calf’s immune system and create future problems." There is also concern about nutrient variability, because a product containing more of a particular nutrient doesn't make it a better choice than another product. Large amounts of specific artificially added nutrients can be toxic.
How is processed milk powder produced? This article explains that: "milk powder is evaporated milk, which is further condensed and processed. During the evaporation process, milk is also pasteurised under controlled temperatures to ward off any bacterial growth." Wiki explains that there are three modern processes: spray drying, drum drying and freeze drying. In this video Dr. Sylvia Onusic PhD Nutrition and Public Health explains why skim milk is often used during spray drying to create milk powder: the spray dry process can turn protein or fat into a "Maillard reaction product that makes al kinds of carcinogens". A European documentary titled Too much Milk in Europe also explores the topic of milk replacer and the fact that vegetable fat is often added to make up for the lack of milk fat.
Milk replacer as it is today was developed for the industrial dairy market.
Feeding waste milk
In this video, Dr Cat Berge explains why it is important to watch what you are feeding calves who are the future milkers because their susceptibility to mastitis can be traced back to their early years. At the 27 minute time marker, she says that waste milk should not be fed to calves because intramammary antibiotic use can lead to more antibiotic-resistance in calf intestinal bacteria. Waste milk has a high microbial risk. In 1945 Sir Alexander Fleming said: “the thoughtless person playing with penicillin treatment is morally responsible for the death of the man who succumbs to infection with the penicillin-resistance organism.”
Raw milk is the perfect food for baby calves / Raw milk provides oligosaccharides and a level of immunity to pathogens
Mark McAfee from the Raw Milk Institute explains in this interview below that raw milk is the first food of life.
"Raw milk's purpose is to transfer the immune system from the mother to the baby and build the gut of the baby."
Consider the following:
This milk from grass- and hay fed animals is about the diverse microbes and the components that feed them.
Raw milk straight from the udder also contains components like lactoferrin and lactoperoxidase that protects the live milk from potential pathogen contamination.
In simple terms, this means that raw milk can enable good microbes to flourish because it naturally contains components that feed it. Raw milk can also eliminate potentially harmful microbes, that may find its way to the milk before they can reproduce.
Microbes and the components that feed them:
In this article research by University California, Davis, Dr. Bruce German shows that human breast milk contains a carbohydrate called oligosaccharides. It is abundant in mother's milk yet human babies cannot digest it. It seems to be there purely to feed microbes and encourage them to settle in the gut. Dr. Bruce's study found that when B. infantis took over the entire lower intestine, it crowded out pathogenic bacteria, which can cause both acute illnesses and chronic inflammation that leads to disease. The studies show that change to the infant's gut may be at the root of rising prevalence of diseases and ailments, from allergies to certain cancers. Good bacteria can prevent deadly infections in babies. Breast milk is raw milk.
Raw cow's milk is also abundant in oligosaccharides. It is part of a system that encourages good microbes to settle in the gut lining that can benefit both calves and humans.
Raw milk contains both the probiotic microbes and the prebiotic food. Oligosaccharides, or complex sugars as they are also known, function as the selective growth substrates for specific beneficial bacteria to grow in the gut. It has also been shown that oligosaccharides themselves, can bind pathogens and protect the infant from infection.
The University of California, San Diego also published a study recently about the benefits of oligosaccharides, the complex sugars in breast milk.
Protective systems in raw milk:
Australian microbiologist Dr Ron Hull has given expert evidence about the safety of raw milk from healthy grass- or hay fed animals. He describes raw milk as having “two systems of immunity to pathogens.” The first he calls “innate immunity.” This comprises a number of factors, such as a set of enzymes, white cells (as in human blood), antimicrobial fatty acids, as well as mineral apatite complexes, with antimicrobial activity. Dr Ron says the existence and function of this innate immunity is well established in the scientific literature. Pasteurisation of milk interferes with complex biological and chemical systems in the milk that begin to be destroyed by heat at 56°C. Pasteurisation destroys many of these anti-microbial and immune-enhancing components, read more here. It is well known amongst farmers that calves fare much better on raw milk than on pasteurised milk.
Farmers producing for the raw dairy market have to focus the health of the animals.
Research now shows that milk fat is where most of the nutrients in raw milk are, and many calves in industrial dairy systems may not be getting enough of it. If RDM is regulated fairly in Australia individual farmers may be able to work out a method of sharing milk between calves and humans. Overseas examples show that this milk sharing is done differently depending on what works best for the unique circumstances at the farm. There is no one size fits all approach.
This New Zealand article says that the 'Pasteuriser unit holds off disease'. This is not entirely true... Many cows and their offspring don't receive nutrient-dense, mineral rich nourishment anymore. The farmers in the article currently rear about 4,500 calves, which they receive from surrounding dairy farms, but they have had to buy a pasteuriser to mitigate the risks of Mycoplasma Bovis, that calves can get from mothers milk. All these calves will be receiving pasteurised milk and milk powder from day one, because they can no longer safely feed raw farm milk. See the Farm and Land, and Cow Health categories to learn how the risk of Mycoplasma Bovis can be mitigated better by learning how nutrient cycling between soil microbes and pasture forage can create a more nutrient-dense, remineralised food that lead to increased animal health.
Also see this very important article about how commercial probiotic supplementation, after antibiotic use, is not a quick fix for humans. The same may be true for calves and cows who are mammals too.
This example is just one out of many that shows how sustainable dairy farming starts with reclaiming the soil fertility, pasture and the transitioning from grain to grass. Farmer Jon Bansen says he had to learn to produce the healthiest, lush grazing material possible. He also learnt to feed his calves plenty of milk and make sure they have plenty of space, and in doing so, he prevents coccidiosis, a condition calves develop when they don't receive enough milk and are forced to live in overcrowded conditions.
Many experienced raw dairy farmers have come to the conclusion that calves fed a natural source of milk are much healthier than bottle-fed calves, see this example.