Lactose intolerance

What is lactose intolerance?

Lactose is a disaccharide consisting of glucose and galactose. In order to break it down and utilize it, the body needs the enzyme lactase, which is produced in the mucous membrane of the small intestine. If the production or activity of lactase is reduced or impaired, the lactose cannot be digested properly and ends up in the large intestine. There it is broken down by bacteria, producing gases and acids that irritate the intestinal wall and lead to the typical symptoms.

Lactose intolerance can have various causes. On the one hand, it can be a congenital disorder in which little or no lactase is produced from birth. However, this is very rare and mainly affects certain dog breeds such as the Border Collie or the Australian Shepherd. On the other hand, it can be an acquired disorder that occurs in the course of life. This can be caused, for example, by damage to the lining of the small intestine as a result of infection, inflammation or medication. Or it may simply be an age-related decrease in lactase production, which occurs in many mammals.

How does lactose intolerance manifest itself in dogs?

The symptoms of lactose intolerance in dogs are similar to those in humans. They usually occur within a few hours of eating food containing lactose and can vary depending on the severity. The most common signs include

• Diarrhea
• flatulence
• Abdominal pain or cramps
• Nausea or vomiting
• loss of appetite
• Restlessness or lethargy

Symptoms may also depend on other factors, such as the amount and type of lactose ingested, the dog's state of health or the presence of other food intolerances or allergies.

How is lactose intolerance diagnosed in dogs?

There are various ways to diagnose lactose intolerance in dogs. The simplest and most cost-effective method is a rule-out procedure. This means removing all foods containing lactose from the dog's diet and observing whether the symptoms improve. If so, you can try reintroducing small amounts of lactose after a while and see how the dog reacts. If the symptoms return, it is probably lactose intolerance.

Another option is a blood test, in which the dog's blood sugar level is measured before and after eating lactose. If the blood sugar level does not rise, this means that the lactose has not been digested and therefore lactose intolerance is present. However, this test is not very accurate and can be influenced by other factors.

A third option is a breath test, in which the concentration of hydrogen in the dog's breath is measured before and after eating lactose. If the concentration rises, this means that the lactose has been fermented in the large intestine and therefore lactose intolerance is present. This test is relatively reliable and easy to perform, but requires special equipment and specialized personnel.

How is lactose intolerance treated in dogs?

The main treatment for lactose intolerance in dogs is to avoid or reduce foods containing lactose. This applies above all to milk and dairy products such as cheese, yoghurt, quark or cream. However, there are also other foods that may contain lactose, such as ready-made food, treats, medication or food supplements. It is therefore important to always check the list of ingredients and ask your vet or the manufacturer if necessary.

There are also some alternatives to lactose-containing foods that are suitable for dogs. For example, instead of cow's milk, you can use goat's milk, sheep's milk or lactose-free milk, which are usually better tolerated. Or you can use plant-based products such as soy yogurt, almond butter or coconut milk, which do not contain lactose, instead of dairy products. However, you should always make sure that these products do not contain any other additives such as sugar, salt or flavorings, which can be harmful to dogs.

If your dog does consume some lactose and shows symptoms, you can help him a little by offering him plenty of water to compensate for the loss of fluids. You can also feed him something easily digestible such as boiled rice or chicken to soothe the gastrointestinal tract. In severe cases, it may also be necessary to give the dog medication to stop the diarrhea or restore the intestinal flora. However, this should always be done in consultation with the vet.

How can lactose intolerance in dogs be prevented?

The best way to prevent lactose intolerance in dogs is to feed them no or only very small amounts of lactose. This is especially true for puppies and young dogs that are not yet fully grown and whose small intestinal mucosa is still more sensitive. You should also make sure that the dog does not eat any lactose-containing food from the table or from the garbage or is fed by other people.

If your dog is already lactose intolerant, you should regularly feed him a high-quality, balanced diet that meets his nutritional needs and supports his digestion. You should also have him examined regularly to identify and treat possible secondary diseases such as deficiency symptoms or intestinal problems.