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Can dogs drink cow’s milk?

Labrador puppy drinking milk advice
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Can a dog drink cow’s milk? Yes, but only in moderation and if she shows signs of being allergic to the ingredients of the milk you should not serve it to her again

By Nick Whittle

Updated on the 19/12/2019, 15:28

Cow’s milk contains a mixture of proteins, carbohydrates, fat, cholesterol, vitamins and minerals. It is not a bad or poisonous food for dogs but it may cause them to have problems (we'll look at some of these in a moment). Therefore, milk should be given to your dog only in moderation.

Milk is a safe treat in small quantities. A few tablespoons of cow’s milk on a special occasion are just right. Too much however causes unwanted side-effects, which include acute diarrhoea and vomiting; too much over a long period of time also brings on obesity.

Can puppies drink milk?

Its mother’s milk is an important source of nourishment for the new born pup. In fact, a puppy needs her mother’s milk more than a human child needs hers. A dog’s milk however is far richer than cow’s milk in protein and calories and much easier for the dog to digest. It also contains a substance called colostrum, which is said to boost a puppy’s immunity.

Puppies have no adverse reactions to their mother’s milk because it contains less lactose (a type of sugar) than cow’s milk.

Why is cow’s milk bad for dogs?

A dog gains everything she needs from a balanced dog diet; in truth, she needs no more than what you give her in her bowl. Furthermore, dog food is these days formulated not just to the size of the dog but to the breed and gender, and some foods are even designed especially for dogs that are poorly.

Feeding her an additional foodstuffs is therefore unnecessary, and most foods processed for human consumption will bring about some unpleasant effects.

Milk allergies

Dairy products (milk, cheese, yoghurt) contain protein that is suspected to be the most likely cause of a dog’s allergic reaction. Unfortunately, they are also the type of foods we most frequently feed to our dog as a special treat.

If you regularly give your dog milk and you notice she is exhibiting the following symptoms, you should consider the possibility that she is allergic to milk protein.

  • Non-seasonal itchiness especially on the ears and paws
  • Chronic or recurrent infections of the ear and skin
  • Vomiting, diarrhoea or excessive gassiness

Although an allergy can be treated (after extensive work on trying to locate the cause), it is the infections of the skin that give further cause for concern. Excessive scratching leads to skin inflammations and further infections, which may then require antibiotic treatment.


Lactose is a type of sugar found in milk. But in order for a non-ruminant (i.e. not a cow or a sheep) to use it, they must first break it down into its component parts, and dogs do not have the ability to do this. That is why dogs become lactose intolerant, because the lactose they ingest sits in the stomach unbroken and causes inflammation.

Many dogs are lactose intolerant, and this fact should be taken into account before you feed your dog a dairy product such as milk. Some other processed dairy products such as cheese and yoghurt are easier for a dog to digest but still contain lactose.

The most common symptoms of lactose intolerance include:

  • Abdominal pain
  • Diarrhoea
  • Gas
  • Vomiting

If your dog suffers with one or more of these symptoms you should consider an alternative treat to milk (and other dairy products); she may well be intolerant of lactose.


The machine of the domestic dog runs on fat. Fat is used by a dog’s body for energy before even protein and carbohydrate, and from fat a dog gains double the energy of those two macro-nutrients. Furthermore, a dog needs fat to survive because some of her vital processes are brought about by the processing of fatty acids.

However, your dog gains the fat she needs from her dog food and to give her any more than what she is already eating can lead to her gaining weight. Too much fat in your dog’s diet leads to obesity (just as it can with humans), and obesity leads to whole raft of other health problems such as pancreatitis, diabetes and even osteoarthritis.

Cow’s milk isn’t toxic for a dog but for dogs that are lactose intolerant, dairy products present a real problem. What's more, a regular diet that includes milk causes your dog to gain pounds and to suffer with the ailments that are associated with being overweight.

There are alternatives such as goat’s milk (which has a reduced amount of lactose and is less likely to cause a protein allergy) and some unsweetened nut milks (almond, soy, etc.) but nut milks tend to be more likely to cause an allergic reaction and the some sweeteners used can poison dogs.

If in doubt, stick to a small dose of cow’s milk but remember: a well-cared-for dog already has all of the nutrients and minerals she needs from a normal diet! Your dog will always enjoy a slurp of milk because she enjoys the sweetness and the fat but not everything she enjoys eating is good for her.

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