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Does your dog like milk? Chances are they do, but did you know that many dogs can have an adverse reaction to dairy products? As a veterinarian, I encounter patients who wonder if their dogs can or should eat dairy, and how to know if dairy causes problems for their pets.
Several components in dairy products, such as the fat, proteins, sugar, and preservatives, can give your dog an upset stomach. In this article, we’ll go over the warning signs that your dog may be having an adverse food reaction to dairy and explain the difference between lactose intolerance and a true allergy to dairy products.
Lactose, a sugar found in milk, is broken down by an important enzyme, Lactase, that newborn puppies have when feeding on their mother’s milk. When puppies are weaned from their mother’s milk, the activity of this enzyme decreases dramatically, which causes them to tolerate only small amounts of milk at a time. Feeding puppies their mother’s milk after they are weaned can lead to signs of lactose intolerance. Also, since cow’s and goat’s milk contain a higher amount of lactose in their milk than canine milk does, feeding puppies and adult dogs cow’s or goat’s milk may lead to diarrhea.
The signs of lactose intolerance can be confused with an allergy to dairy products, when in fact, these are two different adverse reactions. An allergy can occur from a food or food additive found in dairy products and has an immunological (immune system) component to it with systemic consequences. An intolerance, on the other hand, is not immunological, but rather an abnormal physiological response to a food or food additive and can occur after the first ingestion of the food.
Signs of Lactose Intolerance in Dogs
1. Diarrhea
This is the most common sign of lactose intolerance. If you’re noticing an increase in the number of feces your dog produces, or if it’s watery or loose, then your dog may have diarrhea from lactose intolerance. Normal stool should be formed and firm.
This chart is useful for monitoring your dog’s stool and learning what is normal for him or her. With lactose intolerance, you’ll most likely see diarrhea within 12 hours of your dog consuming a dairy product.
2. Vomiting
Vomiting is certainly a common behavior for dogs, but it’s alarming when it happens frequently or with intensity. For dairy-sensitive dogs, vomiting can occur from changes in the gut after eating dairy products.
If you’re dog suddenly starts to drool a lot and/or lick surfaces, this can be a sign that he or she is nauseous and is about to vomit.
3. Lack of Appetite
If your dog isn’t eating, this may be a sign that he or she is nauseous from GI issues. You’ll have to discern whether your dog is just a picky eater or if the lack of appetite is due to the ice cream pint she accidentally got into last night.
A sudden change in appetite is always a concern that something could be going on, whether it’s lactose intolerance, a virus, or an injury. Check with your vet to find out.
4. Bloating
An increase in gas content in the stomach, as well as the small and large intestines, can cause your dog to appear and feel bloated.
The intestines are able to stretch considerably to accommodate changes in ingested food volume and gases produced by bacteria and fermentation of sugars in the gut. However, bloating is uncomfortable when too much gas is present.
5. Flatulence
We’ve all heard or smelled our dog pass gas, and it can be quite funny! While flatulence is usually not a cause for concern, it is a sign that food is fermenting in the gut. Excessive flatulence could be a sign that your dog is lactose intolerant, especially if it occurs after consuming dairy.
What Causes Lactose Intolerance?
PixabayLactose is sugar. It can travel into your dog’s colon undigested if there isn’t enough lactase to break it down. This causes water to be drawn to the sugar inside of the colon, which results in watery loose stool or diarrhea.
Dairy Allergy Signs in Dogs
Lactose intolerance is caused by a deficiency in Lactase, which is not uncommon in adult dogs. Feeding your dog a large amount of dairy can cause diarrhea, vomiting, and other signs of GI upset, because the lactose in the dairy isn’t digested properly.
On the other hand, a canine allergy to dairy products is due to an inability to tolerate the protein in milks (rather than the sugars). This can be more serious and is important to catch early. While some of the symptoms can mimic lactose intolerance, others are quite different. In general, a dog with a food allergy will have a more severe reaction to ingesting the food than a dog with intolerance.
Dairy allergy signs in dogs include:
- Diarrhea
- Vomiting
- Itchiness- excessive ear scratching or licking paws or anus
- Redness of the skin (ears and anus also)
- Hives
- Swelling of the face
- Difficulty breathing
If you suspect an allergy and your dog has hives, facial swelling, or difficulty breathing, see an emergency veterinarian immediately.
What Do I Do If I Suspect an Intolerance or Allergy?
To confirm that dairy is the culprit, simply eliminate dairy products from your dog’s diet and monitor them for a couple of weeks or months to see if there is a decrease in the signs listed above. This includes eliminating treats that contain cheese, human food such as ice cream, table scraps, or other human food that can contain dairy.
If you don’t see a change in the signs after an elimination trial, then evaluate your dog’s condition with a veterinarian who can also consult with a board-certified veterinary nutritionist.
If you’d like to feed your dog milk or yogurt because you want the probiotic benefits, try using a probiotic formula specifically made for dogs such as FortiFlora®. This way your dog gets the benefits of the good gut bacteria without the other extras in milk that could make them sick.