Updated: Dec 16, 2021
Milk especially that from the mother without a doubt is the most important source of nutrients at birth until weaning. It contains beneficial properties such as essential antibodies and colostrum until the young develop their own immune system and antibodies (1, 2). It contains tons of nutrients to sustain life, to grow and develop into strong, healthy adults and naturally made by every mother. However, after infancy milk is no longer needed. In fact, humans are actually the only creatures to not only drink milk after infancy but also milk of another animal.
The milk of various animals is unique to that animal including fat levels, nutrient profiles, and lactose content. Because of this, only the young of that animal should be drinking that milk as most milk of another animal is not comparable.
These figures are one of the many reasons why it is very hard to supplement milk for young that no longer have a mother or one that is not producing milk. The best option is to find another lactating mother of the same species that can act as a wet nurse versus using another species’ milk. If this is not possible obviously you need to do whatever you can for those puppies or kittens.
One question that is always asked is whether dogs and cats are lactose intolerance. The short answer is generally yes. The sugar in milk is called lactose (4). It is a double sugar molecule so in order for a cat or dog to break it down they must have the ability to produce an enzyme called Lactase that can break that bond creating two simple sugar molecules (5). While puppies and kittens do have this enzyme when they are nursing, adult dogs and cats usually can no longer produce this enzyme (6, 7) in significant amounts to break down lactose. As mentioned lactose is present in the milk of mothers who are breastfeeding their young however the lactose in animal’s milk is equivalent to that young’s ability to break down the lactose and therefore varies from animal to animal.
Well, can’t you just use lactose-free milk or a milk alternative like almond or soy milk?
With dogs and cats being carnivores (cats are obligate carnivores) any plant-based products are not properly utilized as cats and dogs are not designed anatomically or physiologically to utilize plant-based products (7, 8, 9). They provide little nutrients and often is just excreted quickly out of the body, therefore, providing little to no benefit to our carnivore companions. Furthermore, soy, in particular, is one of the most genetically modified crops (10). With limited regulation over labeling laws, we don’t have a clear idea of what is actually in many of our food products. We are unsure at this time the true effects of genetically modified crops. Soy also has been shown to mess with estrogen levels increasing them while lowering the function of the thyroid (11, 12, 13, 14, 15, 16).
Milk isn’t the only dairy product that isn’t appropriate for our companions. Other dairy products include cheese, yogurt, ice cream, and cottage cheese. If you do feed your cat or dog dairy products, you will notice varying side effects. This is because dairy products have differing amounts of lactose for example whole milk from cows has 11 grams versus yogurt that has about five. Side effects can include bloating, diarrhea, constipation, gas, and vomiting (17,18). In addition to the lactose in these products may contain high levels of sugar or don’t contain pro/prebiotics which is often the main reason people include them in the diet.
Yogurt is commonly recommended for its pro/prebiotics which aid in digestion. In general, it is recommended that any product meant for digestion is specific to the individual animal and their condition. Probiotic strain, the combination of these strains and the amount of beneficial bacteria probiotic strains per serving is essential to be effective (19, 20). Originally yogurt had these properties but as it has become more and more popular live cultures are a thing of the past while sugar content has sky rocketed. Unfortunately, to reap the benefits of yogurt you would have to feed buckets full to your companion (21) but your companion may suffer diabetic shock as well.
Some of the reasons people add cottage cheese to their companion’s diet are the calcium and protein content as well as being low fat. Not that I recommend feeding kibble or wet canned food, but if you are feeding any kind of balanced diet, your companion does not need more calcium. If too much calcium is given this not only offsets the calcium-phosphorus balance but it can lead to many other problems within the body anatomically and physiologically (22, 23). Protein wise, obviously being carnivores, they need protein but in the big picture of quality protein sources, this is not one of them. Our companions need meat, organs, and bones, not a processed dairy product (24, 25, 26). Finally, for human’s cottage cheese may be a good food item for losing weight but low-fat foods are not needed by cats and dogs even those that do need to drop a few pounds. Dogs and cats thrive on moderate to high-fat diets (27, 28). They don’t get high cholesterol like humans (29, 30). In fact, they need fat to stay healthy (31).
As for ice cream, there is little to no health benefits from ice cream. Any that may exist are almost immediately negated by the high sugar content as well as any other additives like cookie pieces, chocolate swirls, sprinkles, and cherries. Your cat nor your dog, heck even you don’t need to be consuming this dairy product.
Cheese such as parmesan cheese may be suggested to sprinkle on top of raw meals to entice animals to eat but most cheeses are not appropriate on a regular basis. Just like cottage cheese, cheese is high in sodium and is a processed dairy product. It does contain high levels of calcium and protein but again if you are feeding a balanced diet there is no need to add additional calcium. Furthermore, protein from a processed dairy product is not on the same level as quality animal proteins from meats and organs. Although some cheeses contain less lactose (32) never the less some cheeses cause diarrhea where others cause constipation (33).
While your companion may not be lactose intolerant, providing dairy as a source for calcium, protein or probiotics is not the way to go. Anatomically our cats and dogs are designed to consume and break down lactose from their mothers’ milk as infants but as they grow into adulthood this ability is greatly reduced to a bare minimum level. Therefore, it is taxing to the body to provide not only the milk of another animal but also processed dairy products including cheese, ice cream, cottage cheese, yogurt, and milk.
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