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Any food fed to dogs will provoke an argument, but dairy products provoke more than most.
Milk and dairy products are highly regarded because of their protein, calcium, potassium, vitamin D, B vitamins, zinc, and other nutrients. That, and the fact that most dogs love dairy products, mean that milk and other milk-based products remain popular additions to canine diets.
Theories About Issues With Feeding Milk
Healthy infant puppies have no trouble digesting their mother’s milk, but adult dogs are often unable to digest lactose, milk’s naturally occurring sugar. The lactose in cow’s milk is blamed for diarrhea, vomiting, loss of appetite, bloating, flatulence, and other symptoms associated with lactose intolerance.
Until recently, the dairy-for-dogs debate focused on how milk is produced and processed. Today’s dairy cattle are often raised in crowded conditions, fed inappropriate feed, and treated with hormones and antibiotics that leave residues and affect the quality of milk. People who consider milk a perfect food for puppies and adult dogs advocate a return to humane, organic, small-scale, grass-fed dairy farming
Pasteurization is also blamed for reducing the nutritive qualities of milk. Milk is pasteurized to kill harmful bacteria, yeast, and molds; ultra-pasteurization (treatment with higher temperatures) further extends shelf life.
Critics of these procedures claim that pasteurization alters milk’s proteins and destroys its beneficial enzymes. Raw milk is touted by these folks as the solution. The Campaign for Real Milk (realmilk.org) provides updates, resources, and safety information about raw milk. Regulations vary by state, but in several states pet supply stores sell raw milk products for dogs.
Homogenizing has its critics, too. Fresh whole milk separates, with cream rising to the top. Some dairies sell whole milk that has a layer of cream on top but most sell homogenized milk, which has been treated under high pressure to break the cream into small particles, resulting in a uniform mixture. Because the fat molecules in goat’s milk and sheep’s milk are already small enough to create a uniform texture, they are not usually homogenized.
New Theory About Lactose-Intolerance in Dogs
While milk production and processing methods remain key topics, the science of genetics has changed the dairy-for-dogs debate. About half of America’s dairy cows have a mutation that creates a milk protein called A1 beta-casein. Recent research has shown that A1 milk, which is produced by Holstein cattle, America’s most productive dairy cows, may be linked to human health problems such as allergies, indigestion, and even autoimmune disorders.
In contrast, cows such as Guernsey, Jersey, Charolai, Limousin, Norwegian Reds, and Brown Swiss cows have a higher percentage of the older, original A2 gene. More than 200 reports in the medical literature compare the effects of A1 and A2 milk, including “A Systematic Review of the Gastrointestinal Effects of A1 Compared with A2 Beta-Casein” in the September 2017 journal Advanced Nutrition. That study reports that A1 milk consumption is associated with digestive discomfort and inflammatory response markers in rodents and humans.
While no conclusive studies have compared the effects of A1 and A2 milk on dogs, anecdotal reports from veterinarians, breeders, and owners describe dogs with dairy-related indigestion improving on A2 milk.
Milk that is labeled as A2 or A2A2 (which indicates that both parents of the cows that produced the milk had the A2-milk producing genes) is now easy to find in American supermarkets as well as natural food stores.
Other animals that produce A2 milk include sheep, goats, bison, camels, donkeys, and yaks. Any of these milks can be added to food to help ill or aging dogs recover or used as a supplemental food for young puppies.
Can Dogs Eat Cheese?
Dairy products made from milk, especially cow’s milk, can produce no problems at all or acute digestive upsets in dogs. Upsets are usually blamed on lactose intolerance.
Cottage, Swiss, and cheddar cheese contain far less lactose per ounce than whole milk. String cheese or young (rather than aged) cheddar training treats are easier for most dogs to tolerate than aged hard cheeses. Ripened cheeses contain mycotoxins that can be toxic to dogs, such as those found in Roquefort, blue cheeses, and Stilton. The fungi used to make these veined, fragrant cheeses produce roquefortine C, which can cause vomiting, diarrhea, fever, and even seizures in dogs.
Aged, hard cheeses have a high sodium content and so do feta and some other types. Too much salt can harm dogs with heart disease, Addison’s disease, advanced kidney disease, and other conditions that warrant a low-salt diet. Cottage, ricotta, mozzarella, Swiss, and goat cheese are usually low in sodium.
Another concern is the fat content of cheese, which can lead to weight gain and in some cases pancreatitis, a serious illness in dogs. Cheeses that are lower in fat include mozzarella, cottage cheese, and cheeses labeled “low fat” or “reduced fat.” Large quantities of any cheese can create problems, so moderation is your best cheese-feeding guideline.
Whey, a byproduct of cheese-making, has traditionally been fed to farm animals, including dogs. Powdered whey protein is sold as a performance-enhancing sports supplement for canine athletes and for dogs recovering from illness or injury. If your dog might benefit from a whey supplement, consult your veterinarian and adjust the dog’s diet as needed. Liquid raw-milk whey is sold at some stores and farms; see getrawmilk.com.
Dairy and Microbiome
As described in “A Better Biome: Fecal Transplants for Dogs,” WDJ February 2018, microbiome is an umbrella term that describes communities of bacteria, viruses, fungi, and other microbes in the body, especially within the digestive tract.
“Friendly” or beneficial bacteria secrete chemicals that destroy harmful bacteria. If they are present in sufficient numbers, colonies of beneficial bacteria starve harmful microbes by depriving them of nutrients and space. A healthy microbiome is the immune system’s first line of defense.
Lactofermented dairy products are probiotics that support the microbiome and are often recommended for dogs with yeast infections, inflammation, skin issues, allergies, and digestive disorders.
The most famous fermented dairy products are yogurt and kefir, and in recent years both have become popular foods for dogs. They help strengthen the immune system, aid digestion, and restore the body’s beneficial bacteria, especially after treatment with antibiotics.
According to “Modulation of the intestinal microbiota of dogs by kefir as a functional dairy product,” a study published in the May 2019 Journal of Dairy Science, healthy adult dogs had improved gut bacteria after daily feedings of kefir for just two weeks. “Kefir could be further developed as a novel probiotic food supplement for dogs to improve the quality of life of dogs,” the study concluded.
Several types of yogurt and kefir are available in natural food markets and pet supply stores, including fresh or frozen cow’s milk and goat’s milk products, some with added ingredients (check labels). The most affordable way to feed plain, unflavored, sugar-free yogurt or kefir is to make your own, and the process is simple.
Dehydrated live milk kefir starter grains and yogurt starters are readily available (see Amazon.com or CulturesforHealth.com). The fermentation process helps reduce lactose in milk, and so do active cultures, which continue to break down lactose during the cultured milk’s refrigeration.
Making yogurt requires a warm, steady temperature such as in an electric yogurt maker, while kefir ferments at room temperature. If available, try using organic, pasture-raised A2A2 milk or goat’s milk. Store yogurt and kefir in the refrigerator or freeze it for long-term storage. How-to videos at YouTube.com and other sites demonstrate the steps; search online for “make your own yogurt or kefir.”
Begin feeding these foods in small amounts, such as 1 teaspoon per 20 pounds of body weight added to your dog’s dinner. Wait 24 hours and watch for digestive problems such as diarrhea. If your dog enjoys the taste and feels well, add more the next day. Several experts say to feed up to 2 tablespoons of yogurt or kefir per 20 pounds of body weight per day, but many dogs in excellent health eat significantly more. Monitor your dog’s response and check with your veterinarian for the best results.
Can Dogs Eat Ice Cream?
Dogs, like their humans, love frozen dairy treats – but frozen dairy treats may not love them back. Ice cream made with cow’s milk is likely to be high in lactose (and probably A1 milk proteins), sweetened with sugar, high in fat, and artificially flavored. Always check the ingredients; some ice cream contains xylitol, which is seriously toxic to dogs.
Ice cream products that are specially made for dogs are usually lactose- and xylitol-free but may contain sweeteners like maltodextrin, polydextrose, sorbitol, and other questionable ingredients.
Making a healthier alternative can be as easy as freezing plain kefir or yogurt in ice cube trays, popsicle trays, or freezer pop molds. Fresh fruit, peanut butter, or other sugar-free flavorings can be added before freezing along with wooden sticks for holding the treats for your dog.
Let Your Dog Enjoy Dairy!
It’s well known that dogs love dairy! With carefully chosen ingredients, your pups can fall in love with milk-based products that love them back.