Allergies in puppies

Allergies in puppies and canine atopic dermatitis are complex problems that usually cannot be traced to a single cause. Genetics play a role, but genes do not operate in a vacuum. The development of a dog’s immune system may also be influenced by the prenatal environment, the mother’s diet, the puppy’s first foods, early exposure to the surrounding environment and microorganisms, and probably many other factors that we are only beginning to understand.

A Finnish DogRisk study published in 2020 explored exactly this question by analysing data from 2,236 dogs. The researchers examined genetic, dietary and environmental factors both before birth and during the first months of life, then looked for associations with later atopic dermatitis. This was an observational, hypothesis-generating study, so its findings show associations rather than definitively proven causal relationships.

That does not make the findings any less interesting. Quite the opposite. They show very clearly why, when thinking about allergy risk, it is worth looking far beyond the question: “Which ingredient is my dog allergic to?”

Allergy or atopic dermatitis?

Canine atopic dermatitis is a chronic inflammatory and itchy skin disease in which both genetic predisposition and the environment play a role. Typical signs may include persistent itching, licking and chewing the paws, recurrent ear infections, skin redness, and repeated skin or yeast problems.

However, none of these signs is unique to allergy. An itchy dog is not automatically an allergic dog. Parasites, infections, pain, contact irritation and several other problems can create a very similar picture.

Allergies in puppies and genetics

Genetic predisposition is important in atopic dermatitis. In the Finnish study, a maternal history of atopic dermatitis was associated with a higher risk in the offspring, and the risk was also higher in breeds predisposed to allergy.

This is also why breeding from allergic dogs deserves very careful consideration. But genetic predisposition does not mean that a puppy’s future is already carved in stone at conception.

A genetic predisposition does not mean the environment no longer has anything to say.

It is far more useful to view allergy as the result of multiple interacting factors. Genes may make one dog more vulnerable than another, while diet, the skin barrier, the microbiome and early environmental exposures may influence how that predisposition is expressed over a lifetime.

Allergy risk may begin to develop before the puppy is born

One of the most interesting findings in the Finnish study concerned the mother’s diet during pregnancy. Puppies whose mothers received non-processed meat-based food during pregnancy showed a negative association with the later occurrence of atopic dermatitis. The use of ultra-processed, carbohydrate-rich food, on the other hand, was associated with a higher risk.

An important distinction is needed here: the study did not prove that raw food prevents allergy or that dry food causes allergy. It found associations between feeding patterns and later disease.

Nor does “non-processed meat-based food” mean simply throwing random meat into a bowl. A pregnant dog’s diet must be balanced, because both the mother and the developing puppies depend on the right nutrients being present in the right proportions.

At FendaF, we favour variety in a puppy’s diet where possible and the use of high-quality, less processed animal-based foods. This is our practical nutritional approach, not a claim that the study proved one particular feeding method prevents allergy.

The first months of life may be very important

According to the study, the interesting associations do not end at birth. Food and environment during the puppy’s first months may also be linked with later allergy risk.

A lower risk of atopic dermatitis was associated with the use of non-processed meat-based food in early puppyhood, daily exposure to sunlight, and time spent on soil or grass. Normal body condition and being born in the same family in which the dog later remained were also associated with lower risk in the study.

These findings fit well with the broader idea that a developing immune system needs exposure to the real world in order to learn. A sterile environment may not be the goal.

This obviously does not mean deliberately exposing a puppy to pathogens or unsafe environments. It means normal life: moving outdoors, sniffing soil and grass, encountering different surfaces, and being exposed to the natural microbial diversity of the environment.

The sunlight association does not automatically mean vitamin D

The association with sunlight is particularly interesting because, in humans, vitamin D is the first thing that comes to mind. Dogs, however, do not produce vitamin D through the skin in the same way or to the same extent as humans and depend mainly on dietary sources.

For that reason, the sunlight finding cannot automatically be interpreted as “more sun = more vitamin D = fewer allergies”. Sunlight exposure usually also means more time outdoors, more movement and contact with a more diverse environment. These factors are intertwined.

A single association gives us the next question, not always the finished answer.

The microbiome starts earlier than we think

The early-life microbiome is a fascinating area of research in the context of allergy risk. Food, the mother, the living environment and different microbial contacts together influence the microbial world that a puppy’s developing immune system encounters.

The Mordor allergy materials also include early-life probiotic studies in which specific Lactobacillus strains have been associated with changes in allergy-related immune responses. Here especially, however, it is important not to turn one study into a universal puppy protocol.

A probiotic is not an active ingredient called “good bacteria”. Its effect depends on the exact strain, dose, timing of use and whether the bacteria are even viable at the time they are given.

So the importance of the microbiome does not mean that every puppy should automatically receive a jar of probiotics. Diet, environment and lifestyle shape the microbiome too.

A note on deworming

The 2020 study found another interesting association: puppies whose mothers received deworming treatment during pregnancy later had a lower occurrence of atopic dermatitis.

This finding needs further investigation and should not be interpreted as a recommendation to give a pregnant dog an anthelmintic for allergy prevention. Whether medication is appropriate during pregnancy depends on the specific product, the individual dog and parasite risk, and that decision should be made separately.

One observational association is not a new treatment protocol.

It is also worth protecting the puppy’s skin barrier

When discussing the early-life environment, it is also worth thinking about how we care for a puppy’s skin. It is very useful to accustom puppies early to having their paws, ears, teeth and coat handled, because this can make life much easier later.

That does not mean grooming should equal constant shampooing.

Washing too frequently, or using products that are too harsh for the skin, may remove surface lipids and increase dryness and irritation. In a healthy puppy, bathing should be based on actual need and the product used should be suitable for the skin.

At the same time, the current evidence does not allow us to say that frequent bathing in puppyhood causes later allergy. The idea has been proposed, but better studies are needed before such a relationship can be considered proven.

An interesting hypothesis does not have to be thrown in the bin, but it does not need to be awarded a diploma before it has earned one either.

What can a puppy owner take away from all this?

Allergy risk cannot be reduced to zero with one action. Still, the existing material paints a fairly logical overall picture.

When breeding, the parents’ allergy and atopy history is worth considering. A pregnant dog needs high-quality, balanced nutrition. A puppy needs the real world for normal development, not a sterile bubble. Food should be well considered and, where possible, varied; the puppy should spend time outdoors and safely encounter soil, grass and a normal everyday environment. The skin should be cared for, not over-cared for.

And if a puppy develops itching, ear inflammation or paw licking, the first conclusion should not automatically be: “Now the puppy has an allergy.” A symptom needs context and, where appropriate, differential diagnosis.

In summary

Allergy and atopic dermatitis are not the result of one gene, one food or one wrong choice. They are better understood as a complex interaction between genetic predisposition, the immune system, skin, nutrition, microbiome and environment.

The Finnish study is valuable precisely because it suggests that a puppy’s later health may be influenced by exposures that begin before birth and continue during the first months of life. At the same time, the authors themselves clearly state that the associations do not prove causality and that intervention studies are needed to confirm them.

For me, the most important lesson is simple: genetic predisposition does not mean the environment no longer has anything to say.

We cannot control everything, but we can shape a puppy’s start in life so that nutrition, movement, a natural environment, the skin barrier and normal microbial exposure support development as well as possible.

And if allergy does develop, it does not mean there is nothing left to do. The question simply changes from “How can I prevent it?” to “Which factors are keeping this individual dog’s problem going, and which of them can we influence?”