Guide to the dog's intestinal well-being and the importance of the microbiome

A dog's gut microbiota does not form a balanced state overnight – especially the puppy's gut undergoes significant changes early in life. The puppy is born practically sterile, but immediately after birth begins to collect bacteria from its environment. An important first step is the mother's colostrum (first milk), which contains both antibodies and beneficial bacteria. During nursing, the mother's milk and the lactic acid bacteria obtained from it help colonize the puppy's gut with good microbes. Studies show that the guts of nursed puppies contain abundant groups of bacteria such as Firmicutes, Bacteroidetes, and Actinobacteria, which have been shown to promote the puppy's digestion and immune system development[7]. This means that the nutrients and friendly bacteria in the mother's milk create the foundation for the healthy development of the puppy's gut microbiota.

When a puppy is weaned from its mother and transitions to solid food, the gut microbiome continues to develop. During the early developmental stage, the diversity of bacteria gradually increases and a diverse microbiome begins to stabilize[8]. By adulthood, a dog's gut microbes generally reach an "adult level" – a kind of optimal balance where a wide variety of bacterial species are abundant and coexist harmoniously with their host. This balance is influenced not only by diet but also by many other factors such as environment and individual differences. For example, each dog has its own unique microbiota, and even breed and genetics affect the composition of the bacterial population that develops in the gut[9][10].

It is important to note that with age the composition of the gut microbiota can change again. In older dogs, the diversity of gut bacteria may begin to decline and certain beneficial bacteria decrease[8]. One study found that in older dogs the proportion of health-promoting Firmicutes bacteria decreased and the proportion of Proteobacteria group bacteria increased[7]. Excessive growth of proteobacteria is often associated with gut imbalance and increased susceptibility to inflammation. Age-related changes can impair the dog's digestion and immune defense, so special attention should be paid to the senior dog's gut health. The good news is that with the right lifestyle choices – such as quality nutrition and, if necessary, the use of prebiotics or probiotics – it is possible to support the diversity and health of the aging dog's gut microbiota.

In summary: the puppy's gut microbiome needs time and positive influences to develop strongly. The mother provides the important bacteria and nutrients at the start of life, after which a diverse, quality-focused diet and avoiding unnecessary disturbances (such as repeated antibiotic treatments) help the young dog's gut microbes to stabilize. The adult dog's gut is usually quite stable, but its balance must also be maintained – and if the dog is "sensitive-stomached," even small everyday choices (diet, stress management) have a significant impact. For the senior dog, gut well-being becomes especially important, as immunity weakens with age and the gut may need extra support to stay healthy. Next, we will delve more closely into the gut microbiome: what it means and why it is talked about so much when discussing dog health.

The gut microbiome thus refers to all the microbes – bacteria, fungi, yeasts, and viruses – that live in the dog's gut in symbiosis with its host[3]. You can imagine it as a vast, invisible ecosystem inside your pet. In a healthy gut, this ecosystem is very diverse: hundreds of species and billions of cells, each with its own small role. Mainly, the dog's gut bacterial population belongs to the same major groups as in humans: Firmicutes, Bacteroidetes, Actinobacteria, Fusobacteria, and Proteobacteria are typical major phyla of gut bacteria[11]. In a balanced microbiome, beneficial bacteria keep harmful ones in check – they essentially compete for living space so that "bad bugs" do not gain too much foothold.

But why should a dog owner care about gut microbes? Here are some key reasons:

• Digestion and nutrient absorption: Beneficial bacteria help break down nutrients, such as fibers, that the dog's own enzymes cannot fully digest. When bacteria break down fibers, short-chain fatty acids (such as butyrate) are produced, which are the primary energy source for intestinal cells and at the same time protect the intestinal mucosa from inflammation[12][13]. Gut microbes also participate in the production of certain vitamins (e.g., K and B vitamins)[3]. Without a well-functioning microbiota, a dog may not fully benefit from all the nutrients it needs from its food.
• Immune defense: As mentioned, the majority of a dog's immune cells are located in the gut. Gut microbes train the immune system to distinguish harmful pathogens from harmless substances. A good microbial balance helps keep the intestinal wall strong and intact as a protective barrier. A balanced microbiome prevents harmful bacteria from settling in – beneficial microbes essentially take up space and food from them, and even produce acids and other compounds that make the environment unfavorable for pathogens[14]. If the gut microbiota is disturbed (dysbiosis), the number of harmful bacteria can increase excessively, resulting in immune system overreaction or inflammatory conditions[14]. For example, intestinal inflammations, food allergies, and even autoimmune diseases have been linked to unhealthy microbial balance.
• Metabolism and weight management: Gut bacteria affect how efficiently a dog utilizes the calories in its food. Some microbes can enhance energy extraction from food – which may promote weight gain – while others consume energy and produce metabolic products that increase the feeling of satiety. Studies have found links between certain types of microbiota and obesity: for example, a specific bacterial ratio associated with dysbiosis (Firmicutes/Bacteroidetes) may predispose a dog to weight gain[15]. On the other hand, a diverse, fiber-fermenting microbiota produces abundant beneficial fatty acids that suppress inflammation and can support healthy metabolism[13]. Practically, good gut health can help keep a dog at its ideal weight by maintaining a balance between nutrient absorption and energy expenditure.
• Mood and behavior: Dog owners may be surprised that the gut is also connected to the brain. The dog's gut and brain communicate through the nervous system (especially the vagus nerve) and various neurotransmitters[16]. Beneficial gut bacteria produce, among other things, serotonin, GABAa, and other neurotransmitters that can affect the dog's stress levels and mood[16]. In humans, the connection between the gut and mental well-being is recognized, and now research suggests a similar phenomenon in dogs[17][18]. For example, some studies have found abnormal bacterial strains in anxious or aggressive dogs compared to calmer counterparts[5]. Although research is still in its early stages, it can be said that a calm stomach promotes a calm mind – and conversely, chronic stress may manifest as digestive issues in the dog.

In summary: The gut microbiome is a vital part of a dog's health. It affects immunity, nutrient absorption, metabolism, and even the dog's brain. Therefore, it is important to maintain the balance of the microbiota. When the gut is healthy, the dog has more energy, falls ill less often, recovers faster from exertion – and may even be a happier companion in daily life. Next, we will examine the most common problems that can disrupt gut well-being, as well as how to recognize and act in these situations.

Many factors can disturb a dog's stomach function. Most dog owners will at some point encounter a situation where the dog's stomach is upset – most commonly in the form of diarrhea or loose stool. Occasional vomiting, flatulence, or loss of appetite may also indicate that the stomach is not entirely well. Below, we review some common intestinal problems, their underlying causes, and when there is reason to be concerned.

Antibiotics are sometimes necessary, for example, in treating infections, but they can have an unpleasant side effect: they do not distinguish between "bad" and "good" bacteria. Therefore, an antibiotic course may accidentally kill beneficial gut bacteria and disrupt the microbiome balance. For the owner, this may appear as loose stools in the dog during or after antibiotics. Some dogs tolerate antibiotics without problems, while others develop diarrhea or loss of appetite alongside the course.

Studies have shown that antibiotic treatment can significantly alter the composition of a dog's gut microbiota – even in a short time, the number of beneficial bacteria decreases, and some more resistant strains (or yeasts) can take over[20]. Such dysbiosis can predispose to other health problems because the gut's defense mechanisms weaken. For example, after antibiotics, a dog may be more susceptible to new diarrhea or intestinal inflammation while the normal bacterial population is still recovering.

How to support a dog's gut during an antibiotic course? Prevention is the key: unnecessary antibiotic courses should be avoided – use them only under a veterinarian's prescription, for the correct purpose, and follow the instructions to complete the entire course. Sometimes there are alternatives for ailments (e.g., probiotics or supportive treatments for milder intestinal inflammations), but these decisions always belong to the veterinarian. When antibiotics are necessary, gut microbes can be supported, for example, with lactic acid bacteria (probiotics). There is research evidence that certain probiotic strains may shorten the duration of antibiotic-associated diarrhea and help restore the microbiota balance faster. Ask your veterinarian for a suitable product – usually, probiotics designed for dogs are recommended during and for a few weeks after the course. Also, prebiotics (dietary fiber that feeds good bacteria) can be beneficial during recovery; a fiber-rich, easily digestible diet helps good microbes grow back. However, remember that every dog is an individual: monitor how your dog reacts and report to the veterinarian if you notice significant side effects. If necessary, another supportive treatment or medication can be substituted alongside the antibiotic if the gut does not tolerate the medicine well.

On the positive side, the gut microbiome is usually quite resilient: it can recover over time. The recovery of beneficial bacteria can be promoted intentionally: there are dog foods supplemented with prebiotics (such as FOS, MOS, or root fiber) to help restore balance, and sometimes a veterinarian may suggest synbiotic products (a combination of prebiotic and probiotic). A scientific review states that restoring the beneficial bacterial population after antibiotics is essential for gut health – so make sure your dog receives gut-friendly nutrition and a calm recovery period after the course[21]. Avoid unnecessary stress immediately after the antibiotic course (let the dog rest, maintain a familiar daily routine), as stress can worsen dysbiosis further[21].

Some dogs seem to react sensitively to even the smallest changes – they can be called sensitive-stomached. A sensitive-stomached dog may have recurring loose stools or occasional vomiting without an obvious underlying cause. Typically, these are dogs that may have, for example, mild gastrointestinal hypersensitivity to certain foods or whose intestines react strongly to stress. For instance, traveling or new food may cause stomach aches. With a sensitive-stomached dog, the owner often learns through experience to avoid certain foods or situations known to cause problems.

What can cause a sensitive stomach? One common reason is food intolerance or allergy. Proteins such as beef, chicken, dairy products, wheat, or soy commonly cause hypersensitivity in dogs. If a dog has such a hypersensitivity, its intestines may become mildly inflamed whenever exposed to the substance, which manifests as stomach symptoms. Another possible cause is mild inflammatory bowel disease (IBD/CIE), where the intestinal immune system is overactive and causes chronic inflammation; there are many causes (genetic predisposition, immunological abnormality, microbiota imbalance), and it requires a veterinarian's diagnosis. IBS (irritable bowel syndrome) is a term sometimes used to describe a functional disorder where no clear physical cause is found, but stress and diet affect symptoms. A sensitive stomach can be a dog's "trait" – somewhat like in some humans – where with the right diet and routines the dog remains symptom-free, but deviations can quickly cause symptoms.

How can a sensitive stomach be helped? First of all, regularity and consistency are your friends. Keep the dog's diet as simple and high-quality as possible: choose easily digestible complete food, avoid constant brand or protein changes, and do not feed large amounts of stomach-challenging treats (such as very fatty meats or milk if the dog is lactose intolerant). Many dogs with sensitive stomachs benefit from a fiber supplement that binds water in the intestine and balances stool consistency – you can ask a veterinarian about using psyllium fiber or other soluble fibers. Prebiotics (such as inulin, FOS) in food can feed beneficial gut microbes and strengthen the intestinal mucosa[22]. Probiotics may also help with continuous use to support gut immunity; certain probiotic products are designed for long-term use, but it is good to discuss these with a veterinarian to select the right strain and dosage. Stress management is important for a dog with a sensitive stomach – try to keep daily routines as consistent as possible, provide the dog with a safe place and peace to rest, and gradually accustom it to changes. For example, if you know you are going on a trip, you can prepare the dog in advance by taking short car rides and packing its familiar food and perhaps a product that helps with motion sickness if that is helpful.

It is also important to recognize when chronic issues require veterinary examinations. If the dog has continuously recurring episodes of diarrhea, noticeable weight loss, blood in the stool, or abdominal pain, it should not be assumed to be "just a sensitive stomach." In such cases, examinations are warranted – blood tests, stool samples for parasites, possibly feeding trials to confirm allergies, and in some cases endoscopy – to ensure any diseases are treated. Often, treatment of chronic intestinal problems includes diet customization (e.g., elimination diet for allergies or highly hydrolyzed special food for IBD dogs) as well as medication or supplements as needed.

In summary: A sensitive stomach requires attentiveness and effort from the owner, but with the right actions, the dog can live a completely normal, happy life. Identify your dog's sensitivities, avoid them as best as you can, and proactively support gut health with high-quality nutrition and good bacteria. Remember that help is available – do not hesitate to consult a veterinarian if you feel you cannot balance your dog's stomach by your own means. Together you can find solutions, whether it is a special diet or another treatment method, so that the sensitive stomach no longer hinders the dog's activity.

Diet is perhaps the most powerful single factor that shapes the composition of a dog's gut microbiota daily. What the dog eats is also food for the gut bacteria – different nutrients feed different microbes. Therefore, it matters what is put in the bowl. Broadly speaking, the amounts of protein, fat, and fiber in the food directly affect which bacteria thrive in the dog's gut[23].

Studies have shown that a high-protein diet (for example, a diet based solely on meat or very high in meat) favors certain groups of bacteria. Dogs eating a lot of meat have been observed to have an increased abundance of, among others, Fusobacteria bacteria and some protein-degrading bacteria[24]. They participate in amino acid fermentation and can produce metabolic products such as butyrate, which also has beneficial effects (butyrate suppresses inflammation in the intestine)[12]. However, an overly monotonous, extremely protein-rich diet can leave beneficial fiber-degrading bacteria "without nourishment" – if the dog receives no carbohydrates or fibers at all, bacteria of the genera Bifidobacterium and Prevotella receive less. Fibers (and other prebiotic carbohydrates) are therefore invaluable for gut microbes: they are not absorbed in the dog's small intestine but end up in the large intestine to be utilized by microbes. When good microbes ferment fibers, short-chain fatty acids (SCFA, such as acetate, propionate, butyrate) are produced, which lower the pH of the intestine, inhibit the growth of harmful bacteria, and nourish the cells of the intestinal wall[25][12]. According to studies, a fiber-rich diet is associated with a higher amount of beneficial bacteria, including an increase in bifidobacteria and bacteria of the genus Faecalibacterium[22]. For example, inulin and fructo-oligosaccharides (FOS) are prebiotic fibers that have been shown to increase the proportion of beneficial microbes and promote butyrate production in the intestines of dogs[22]. Some functional fiber sources, such as potato fiber, have also been shown to improve intestinal conditions: when fiber derived from potato was added to the diet, the amount of Firmicutes bacteria increased and Fusobacteria bacteria decreased, indicating a favorable change in the microbiota[26].

The fat content in the diet also affects the microbes. Very fatty food can cause loose stools in some dogs (fat is less well digested) and shift the microbiome composition towards a less acidic gut environment, where some harmful bacteria thrive. On the other hand, healthy fats, such as omega-3 fatty acids, can be beneficial: there is evidence that omega-3s reduce harmful bacteria (such as those producing inflammatory LPS endotoxins) and support the growth of beneficial bifidobacteria[27]. Thus, the quality of fat is essential – EPA and DHA from fish oil can protect the gut, whereas excessive saturated fat may disrupt the balance if given in large amounts.

What about the form of the diet? There are various feeding philosophies on the market: industrial kibble, home-cooked food, raw food, plant-based feeding... All of these affect the microbiome. For example, dogs on a raw diet have been found to have greater bacterial diversity and especially an increase in the genus Fusobacterium compared to those eating kibble[24]. Dogs eating dry food, on the other hand, may have more Prevotella bacteria, which is likely related to the higher carbohydrate content. Interestingly, a recent study found only small differences in the gut microbiome of healthy dogs when comparing a completely plant-based (vegan) diet and a typical meat-based diet[28]. This indicates that the canine gut microbiome can adapt to quite different diets without dramatic changes – assuming the diet is nutritionally complete. More important than the formal classification of the food is its nutritional content and how dietary changes are implemented. Rapid changes can disrupt the balance: when the bacterial population is accustomed to one diet, a sudden change in nutrient composition can cause a temporary imbalance (and diarrhea). Therefore, new food should always be introduced gradually by mixing it with the previous food over several days or weeks.

Overall, a good rule of thumb is to offer the dog a varied and high-quality diet that contains protein, fat, and fiber in appropriate proportions. High-quality meat or fish as a protein source provides building blocks and palatability, while fibers (vegetables, root vegetables, whole grains, or separate fiber supplements) feed the bacteria important to the gut. Individual differences must also be taken into account: one dog may do excellently on grain-containing kibble, while another needs a grain-free diet to avoid skin or stomach problems. Tailor the diet to your dog and consult an expert if necessary (a veterinarian or a pet nutrition specialist) for advice on feeding suitable for your dog – especially if your dog has health problems that diet can affect.

Finally, it is important to emphasize: what a dog does not eat is as important as what it eats. Keep trash and spoiled food scraps out of reach, do not let the dog gulp large amounts of human foods (many of which can cause stomach problems or be dangerous, such as chocolate, xylitol, onion, etc.), and be careful not to feed too many fatty treats. Balance and moderation are key words. Gut microbes appreciate consistency and nutrient richness – they thrive when they constantly have good fibers and a suitable amount of indigestible material to ferment, but they suffer if the diet consists of only one type or the gut receives continuous shocks from inappropriate ingredients.

In recent years, pet health writing has increasingly encountered the terms prebiotic, probiotic, and postbiotic. They easily sound very similar but mean different things. All of them are related to gut microbes: it is either about the gut bacteria themselves or their nutrition and products. This chapter clearly explains what each of these terms means, what they are used for, and what benefits they can have for a dog's gut.

Prebiotics are substances that themselves are not nutrients for the animal, but that feed beneficial gut microbes. Generally, prebiotics are various fibers or carbohydrates that the dog's digestive enzymes do not break down, but which end up in the colon to be broken down by bacteria[29]. Thus, a prebiotic acts like a fertilizer: it promotes the growth and activity of desired bacteria in the gut[29]. Examples of prebiotics include inulin, fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), resistant starch, and pectin. Many of these occur naturally in vegetables and fruits – for example, Jerusalem artichoke, chicory, banana, apple, and carrot contain prebiotic fibers. Prebiotics are often given to dogs as part of complete nutrition (many high-quality dog foods contain added FOS or root fiber) or as separate fiber supplements.

What are the benefits of prebiotics? As mentioned earlier, prebiotics increase the amount of beneficial bacteria (such as bifidobacteria) and the production of SCFA acids they produce[22]. This leads to a lower pH in the intestine, which prevents the growth of harmful bacteria. Prebiotics have been found to improve digestive efficiency, stool composition (e.g., reducing constipation or alleviating excessive looseness fluctuations), and even immune defense through their microbiota-modulating effects[22]. In other words, by giving the gut "good food," we support the dog's health. Prebiotics are generally well tolerated, but in very large doses they can cause gas formation (because fermentation also produces gases). Therefore, if you add prebiotic fibers to your dog's diet, do so gradually – to avoid accidentally causing flatulence or stomach cramps due to too sudden a change.

Probiotics, on the other hand, are live microbes given to dogs to promote health. According to the World Health Organization WHO's definition, probiotics are live microorganisms which, when administered in adequate amounts, confer a health benefit on the host[29]. In practice, probiotics include certain bacterial species or strains also found in a healthy gut microbiome. Common bacterial genera used as probiotics include Lactobacillus (lactic acid bacteria), Bifidobacterium, and Enterococcus. Probiotic products developed for dogs may contain one or more carefully studied bacterial strains known to have beneficial effects in the canine gut.

How do probiotics work? Think of it as bringing reinforcements to the gut in the form of an army of good microbes. When a dog is given probiotics, they settle at least temporarily in the gut to compete with harmful bacteria. They can produce bacteria-destroying substances (bacteriocins), displace pathogens by attaching to the intestinal lining ahead of them, and they can also modulate the immune system towards a calming direction. Probiotics have been found, for example, to shorten the duration of diarrhea in dogs, reduce antibiotic-induced intestinal disturbances, and possibly help with some skin problems and allergies (such as atopy) by balancing the immune response[30]. Some studies even suggest that probiotics might have a mild anxiety-relieving effect in dogs – likely through the gut–brain axis, as has also been observed in humans[31][32]. It is important to note that not all probiotics are the same: effects are strain-specific. For example, Enterococcus faecium is a common bacterium used in dog probiotics, with certain strains proven safe and beneficial, e.g., in preventing diarrhea in puppies. In contrast, Lactobacillus rhamnosus GG is a well-known potent probiotic in humans, but its effects in dogs have been less studied.

Sources of probiotics: There are several commercial probiotic products available for dogs – pastes, capsules, powders, chewable tablets. Their composition and efficacy vary. It is usually safest to use products recommended by veterinarians, where bacterial strains and amounts are clearly indicated. Probiotics can also be obtained from natural sources: some owners give their dogs a little buttermilk, natural yogurt, or sauerkraut mixed with food. These contain lactic acid bacteria, but it is important to remember that not all dogs tolerate dairy products (lactose intolerance is common in dogs). Additionally, with natural products, you do not know exactly which bacterial strains and how much the dog receives. Therefore, for sensitive dogs or in more serious conditions, it is advisable to use standardized products. Probiotics are often given as a course – for example, 5–10 days in cases of diarrhea – but in some cases (such as chronically sensitive stomachs), a veterinarian may recommend longer use. They are quite safe, but very rarely, in debilitated individuals, there is theoretically a risk that live bacteria could cause problems; for this reason, probiotic treatment for very seriously ill or immunocompromised animals should always be discussed with a veterinarian.

Is it worth giving probiotics to a healthy dog? Opinions vary on this. Some say that if the dog's stomach functions perfectly, extra probiotics are of no benefit. Others believe that the modern environment and processed food impoverish the microbiota, so additional probiotics are always helpful. Current research seems to support the idea that probiotics can also be beneficial preventively: they may maintain the healthy structure of the intestinal villi, improve nutrient absorption, and strengthen immunity[33][34]. Generally, a healthy dog does not need continuous probiotic courses if it eats quality food and is in good health. Occasionally – for example before a stressful situation (travel, competition) or a change in diet – probiotics can help keep the gut calm.

Postbiotics are the newest addition in this trio. The term may be unfamiliar to many. Postbiotics refer to beneficial compounds or products produced by probiotics, or alternatively whole parts of microbial cells that have been inactivated but still have health effects[35][36]. In other words: when probiotics consume prebiotics, they produce postbiotics. A good example of a postbiotic is the previously mentioned butyrate (butyric acid), which is the end product of fiber fermentation by lactic acid bacteria. Butyrate has a strong anti-inflammatory effect and strengthens the intestinal wall[13]. Other postbiotics include lactic acid, bacteriocins (proteins produced by bacteria that combat competing bacteria), various enzymes, peptides, and cell wall components (such as teichoic acids). The essential point is that a postbiotic is not alive – it is either a part of a dead bacterium or a chemical compound secreted by a bacterium[37]. For this reason, postbiotics are often very stable: they can be added, for example, to pet foods or supplements without concern for the viability of live bacteria.

What are the benefits of postbiotics? Although postbiotics are not alive, they can mimic the effects of probiotics in the body. For example, some postbiotics bind to the intestinal mucosa and stimulate the immune system in a controlled manner – as if training it without the risk of infection. Several studies suggest that postbiotics can improve the composition of the gut microbiome, suppress excessive inflammatory responses, reduce oxidative stress in cells, and help manage chronic diseases (such as skin problems or intestinal diseases)[30]. For example, in one study, administering a postbiotic-containing preparation to dogs reduced symptoms of atopic dermatitis, indicating an immune-mediated effect on skin health via the gut[30]. Postbiotics also have the potential to serve as a alternative to antibiotics in certain situations, as they can inhibit the growth of harmful bacteria without the risk of bacteria developing resistance[38].

Since postbiotics are a new concept, research on them is still ongoing. However, products such as dog foods advertising "postbiotic fermentation product" as an ingredient have started to appear on the market. This may mean, for example, dried fermented yeast or lactic acid bacteria fermentation products that provide compounds beneficial to the gut. Postbiotics are promising because they are safe (no live microbes, so no infection risk), stable, and can offer the same benefits as probiotics. It is still important to remember that they do not replace the living microbiome – they are rather targeted tools for managing specific issues.

Prebiotics, probiotics, and postbiotics can be seen as a continuum: they complement each other. Prebiotics are the fuel that helps beneficial microbes (natural or given as probiotics) grow and thrive. Thriving microbes, in turn, produce beneficial postbiotics that provide health benefits to the gut and the entire dog[39]. It can be considered that if one wants to support the dog's gut, often pre- and probiotics are combined (synbiotic): probiotics add more good bacteria, and prebiotics feed both old and new beneficial microbes. This results in more postbiotics being produced, and the gut environment becomes favorable. In this sense, all three can be utilized in maintaining gut health.

Practical example: Your dog has had a course of antibiotics, and you want to help its gut recover. The veterinarian may suggest a synbiotic product containing both probiotics (e.g., Enterococcus faecium strain) and prebiotics (e.g., FOS fiber). You give this to the dog daily for a couple of weeks. The probiotics settle in the gut and the prebiotic feeds them – they start producing postbiotics such as butyrate, which repairs the intestinal lining and reduces inflammation. Additionally, probiotics temporarily inhibit the growth of harmful bacteria. As a result, the dog's stool becomes firmer and gut function normalizes faster than without supportive treatment[40]. Such a "triple therapy" is becoming more common in both humans and animals, reflecting how important microbes and their nutrients are for well-being.

In summary, these terms: - Prebiotic = fiber or other compound that feeds good bacteria (e.g., inulin). - Probiotic = live good bacteria given to support health (e.g., lactic acid bacteria). - Postbiotic = product of good bacteria or inactivated bacteria with health effects (e.g., butyrate or heat-treated lactobacillus)[41].

These can be used separately or together for your dog's gut health. It is always good to discuss with an expert what your own dog might need – each one is an individual, and unnecessary supplements should not be given. Next, we provide general practical tips to support your dog's gut well-being in everyday life.

With small everyday actions and choices, you can significantly influence your dog's gut microbiota well-being. Below is a collection of tips and good practices that help keep the stomach content and the microbes in harmony. These tips benefit both puppies and adult dogs' intestines – and many of them are the same things that generally maintain a dog's overall health.

• Provide high-quality, balanced nutrition: The basis of feeding should be a complete dog food that provides all the nutrients your dog needs. Choose a food that suits your dog's age, size, and special needs. High-quality food often naturally contains or is supplemented with fibers beneficial to the gut (such as root fibers, flaxseeds, or other prebiotics). Avoid diets that are very monotonous or contain too many fillers – remember that variety (the appropriate balance of different nutrients) maintains a diverse microbiome.
• Maintain feeding routine, but avoid sudden changes: A dog's gut appreciates regularity. Feed your dog at roughly the same times every day and avoid constant brand changes without good reason. If you change the dog's food, gradually introduce the new food by mixing it with the old food over a 7–10 day transition period. This allows the gut bacteria to adapt to the new food, preventing imbalance. For puppies, remember that from the weaning period onward, it is important to proceed step by step with food – too large changes can be a shock to a small stomach.
• Maintain hygiene, but let the dog be a dog: Microbes from the environment are part of the gut ecosystem. Allow the dog to sniff and explore its surroundings outdoors – this exposes it to a variety of environmental microbes, which can even enrich its gut microbiota (for example, roaming in the forest and digging in the soil introduce soil bacteria to the gut, which may support a diverse microbiota). On the other hand, prevent the dog from eating trash, carcasses, or other animals' feces, which can harbor harmful bacteria or parasites. Balanced hygiene means not keeping the dog in a sterile bubble, but also not allowing it to constantly gobble up everything possible. At home, wash the dog's food bowl regularly and store food hygienically to avoid spoilage.
• Practice stress management: A dog's mental state affects its stomach. Stress can alter intestinal motility and even the microbiota (for example, stress hormones can reduce certain beneficial microbes in the gut). Therefore, aim to maintain routine and security in the dog's life. If a stressful event is anticipated (e.g., fireworks on New Year's Eve or a veterinary visit), prepare the dog in advance: use natural calming support products if necessary (such as pheromone diffusers) and provide extra security and familiar items (own bed, toy) during stress. Some dogs benefit from a probiotic course before a stressful situation – studies have shown that probiotics may help dogs better withstand stress, for example during travel[21]. The most important thing is to identify the sources of stress and strive to minimize unnecessary burden.
• Exercise and weight management: Regular exercise keeps the bowel moving as well. Daily walks and play help digestion function normally and prevent constipation. Overweight has been shown to affect gut microbes – obese dogs may have a different microbiome composition than lean ones, and obesity predisposes to, among other things, low-grade inflammation in the body. Keeping your dog lean and in good muscle condition also supports its gut health. However, remember to avoid heavy exercise immediately after eating, especially in large breeds, as it can predispose to gastric torsion and digestive disorders.
• Water, water, water: Ensure that your dog always has access to fresh water. Adequate hydration is vital for bowel function – water softens the stool and helps dietary fibers swell and do their job. Especially in cases of diarrhea, the need for water is emphasized because more fluid is lost than normal. If necessary, you can flavor the water, for example, with a small drop of meat broth if the dog is reluctant to drink, or offer moistened food to ensure sufficient fluid intake.
• Protect yourself from parasites: Intestinal parasites (such as roundworms, hookworms, and Giardia) can cause ongoing stomach problems and damage the gut microbiota. Follow your veterinarian's recommendations for regular deworming – especially puppies and dogs that meet many other dogs or hunt voles in the wild should be examined and dewormed regularly. Collect your dog's feces from the environment to reduce the spread of parasites. If your dog has prolonged diarrhea, the veterinarian usually first rules out parasitic infections, for example, by fecal sample testing. So take care of this aspect as well, so that worms or protozoa are not behind intestinal problems.
• Consider pre- and probiotics as part of daily life as needed: Not all dogs need to eat supplements, but in certain situations they can be beneficial. For example, if your dog is known to have a sensitive stomach, you can consult your veterinarian about the continuous use of a prebiotic or probiotic product as part of the diet. Some complete foods already have prebiotics added (such as chicory root or mannan-binding fiber) to support the gut daily. Fermented foods and treats have also appeared on the market, containing natural postbiotics – for example, fermented dog food or products suitable for dogs made from sauerkraut. These can be beneficial, but always remember to introduce new things gradually. Also note that too much is too much: excessive fiber supplementation or too many different bacterial products at the same time can even disrupt the gut. One thing at a time, and monitor the effects.
• Observe your dog's stool and condition: A dog's poop tells a lot about the state of its gut. Ideally, the stool is formed, firm but not hard clumps, and brown. Learn to recognize what is normal for your own dog. If you notice changes – looseness, mucus in the stool, very pale or black color, foul-smelling gas, difficulty defecating, etc. – pay attention to what might have changed (feeding, stress, etc.). Many gut problems are easier to solve when detected early. The stomach does not become painful "suddenly without reason," but often some factor is behind it. The dog's condition (energy, appetite, drinking) together with stool quality provides an overall picture: if the stool is loose for a short time but the dog is otherwise normal, you can continue to monitor; but if the loose stomach continues and the dog appears sick or lethargic, action is warranted.
• Do not hesitate to seek help: Although many stomach issues are mild, it is always better to ask a veterinarian for advice than to remain uncertain. There is now specialized expertise available for canine gut health: there are veterinarians specialized in internal medicine for dogs, nutrition counseling professionals, and even tests that can analyze the composition of a dog's gut microbiota. If you struggle with your dog's ongoing gut problems, professionals can help determine whether the cause is, for example, intestinal inflammation, pancreatic enzyme deficiency, or a rarer issue, and create a treatment plan. Many gut problems can be managed by combining the right diet, necessary medications (if, for example, the pancreas does not produce enzymes, enzyme powder is added to the food), and gut-supporting supplements. You are not alone in this matter – digestive issues in pets are among the top 3 reasons for veterinary visits, so plenty of help and information are available.

Even small actions can influence the happiness of your dog's gut microbes. Remember that the cornerstones of gut well-being are high-quality nutrition, regularity, appropriate exercise, stress-free conditions, and targeted support when needed (such as pre/probiotics). Next, we will move on to the guide's FAQ section, where you will find answers to frequently asked questions about the dog's gut and microbiome.

The dog's gut microbiome refers to all the microscopic organisms (such as bacteria, yeasts, protozoa) living in the dog's digestive tract. They are most abundant in the large intestine, where they form a complex community. The microbiome lives in symbiosis with the dog – it helps with digestion, vitamin production, and immune defense, among other things. A good microbiome balance (eubiosis) means that beneficial bacteria dominate and keep potential pathogens in check. A disturbed microbiome (dysbiosis), on the other hand, means that the balance is disrupted, for example, an inappropriate bacterium has become prevalent or diversity has narrowed, which can lead to health problems.[1][6].

One of the most important signs of a healthy gut is normal stool. A healthy dog's stool is firm, shaped, and easy to pick up; neither watery nor rock hard. The frequency of bowel movements is also characteristic for the dog (usually 1–3 times a day for an adult dog), and the rhythm is fairly regular. The dog's general well-being reflects the state of the gut: when the stomach is fine, the dog is energetic, eats with good appetite, has a shiny coat, and healthy skin. Flatulence and burping should be quite rare – constant foul-smelling gas may indicate poorly digestible food or bacterial imbalance. Weight management also proceeds well: if the dog's weight remains ideal with the same amount of food, it suggests that nutrients are absorbed normally. A healthy gut usually neither makes noise nor is particularly noticeable in daily life – it does its work in the background. You can think that when your dog's stomach works like clockwork and you don't have to constantly worry about its stool or appetite, the gut is probably doing well!

Yes – occasional mild diarrhea or a single episode of vomiting is part of almost every dog's life, just as humans can get a stomach bug or have some food "pass through." For example, a small dietary change, eating too many treats, or ingesting something unclean outdoors can cause a single day of diarrhea that passes quickly. Similarly, dogs may sometimes vomit after eating too quickly (so-called regurgitation) or, for example, yellow foam (bile secretion) on an empty stomach – this can also be normal for some dogs occasionally. It is important to monitor that after the transient issue, the dog returns to normal: diarrhea should settle within 1–2 days with home care, and vomiting should stop when the stomach is rested.

If loose stools or vomiting occur frequently (e.g., weekly), or if they are accompanied by other symptoms such as weight loss, continuous loss of appetite, or abdominal pain, then the condition is no longer "normal" and should be examined more closely. In other words, isolated cases are usually harmless, but recurring symptoms require intervention. Puppies should be treated more cautiously: their immune system is weaker, and diarrhea can cause rapid dehydration, so it is important to be vigilant and rather visit the veterinarian once unnecessarily than be late with getting help.

Whenever a dog's symptoms are severe, prolonged, or general condition worsens, it is advisable to consult a veterinarian. Here are some guidelines: - If diarrhea is very severe or bloody, or if it is accompanied by continuous vomiting, it is advisable to go to the veterinarian immediately (there is a risk of dehydration and possibly a serious underlying cause). - If the dog repeatedly vomits all the water it drinks or the food it eats, it needs help (a vomiting dog becomes dehydrated and it may be a sign of an obstruction or similar). - High fever, weakness, seizures, clear abdominal pain (the dog tenses up, whines when touched, lies in an unusual position) are warning signs – related to the intestines, they may indicate, for example, a foreign object in the intestines, pancreatitis, or another serious inflammation. - In the case of puppies and elderly dogs, I would be more inclined to go to the veterinarian even after a day of vomiting or diarrhea, because their bodies dehydrate and weaken faster. - If the dog has chronic intestinal symptoms, such as continuous looseness for weeks or recurring episodes of symptoms, it is advisable to book an appointment for examinations. The most common cause of chronic diarrhea is food allergy[42], but this must also be confirmed by excluding other causes. - Whenever you are unsure, it is better to have it checked. Veterinarians prefer to see a patient "unnecessarily" rather than waiting too long at home.

Basic examinations can be performed at the veterinarian (listening to the intestines, palpating the abdomen, possibly taking blood tests and stool samples). Often in acute cases, treatment includes hydration, anti-nausea medication, and protective medication for the intestines as needed – and of course treatment of the underlying cause (for example, antibiotics if there is a strong bacterial infection, or deworming if parasites are found).

Checklist: Take the dog to the vet if: bloody or very severe diarrhea, continuous vomiting, inability to keep fluids down, the dog appears sick/tired, symptoms last more than 2 days without clear improvement, or whenever you suspect something more serious than normal. Better too early than too late!

It can have an effect. In dogs – as in humans – the gut and nervous system are closely connected. When stressed, the body releases stress hormones (such as cortisol and adrenaline), which can affect bowel function: bowel movements may speed up (resulting in looser stools) or, on the other hand, some dogs may hold back defecation when stressed and develop constipation. A typical example is a dog that goes to a daycare or unfamiliar place and gets diarrhea from nervousness. Stress can also alter the balance of gut microbes. Chronically stressed dogs have been found in some studies to have a different microbiome composition – for example, a deficiency of beneficial bacteria and an increase in some bacteria that grow under stress[18]. As a result, long-term stress can predispose to intestinal inflammation or worsen existing problems. Additionally, a dog with stomach issues may become more stressed, which is an unfortunate vicious cycle.

In practice, many dog owners report that their dog has a "nervous stomach": for example, on show or competition days, the dog defecates more frequently and with looser stools. Or during thunderstorms and fireworks, a timid dog may tremble and soon be found on the floor with a loose pile. These are very concrete examples of how mental state and physiology are interconnected.

It is important to note that not all dogs react to stress in their stomach – individual differences are significant. In any case, the connection between the gut and the brain is a scientifically proven phenomenon, known as the gut–brain axis. The good news is that the effect also works in the other direction: if we support gut health (e.g., with probiotics), we can alleviate the effects of stress. One study mentions that the use of probiotics combined with prebiotics helped stabilize the gut microbiota of dogs in stressful situations, even though the stressor itself was present[21]. So yes, stress affects the stomach – but we can try to influence it either by reducing stress or by supporting the stomach, preferably both.

These three terms are easily confused. In summary: - Prebiotics are food for good bacteria. Often fibers that feed beneficial microbes living in the gut and promote their growth[43]. Prebiotics are obtained from food (fibers in vegetables, grains) or as supplements, and they indirectly improve gut conditions. - Probiotics are live good bacteria. They are given orally and settle in the gut to provide health benefits[43]. They compete with harmful microbes and support the immune system. Probiotics are found, for example, in lactic acid bacteria products. - Postbiotics are beneficial substances produced by good bacteria or inactivated microbes. They are not alive but have health effects, such as anti-inflammatory or gut wall-protective effects[35][36]. An example is butyric acid or, for instance, fragments of the cell wall of heat-treated probiotics. Postbiotics can be obtained from fermented products or separate preparations.

Simply put: prebiotics feed probiotics, which produce postbiotics. The goal is to have more good bacteria (probiotics) in the gut and to utilize their beneficial effects (postbiotics).

If your dog is completely healthy, the stomach functions excellently, and there are no special risk factors, separate supplements are generally not needed. Quality dog food usually provides enough fiber (prebiotic) to maintain a normal microbiota. The dog also naturally receives probiotics from the environment (e.g., soil bacteria). Unnecessary supplementation may not be beneficial and can be a waste of money.

However, there are situations where even a healthy dog may benefit from pre- or probiotics: - When changing diet (e.g., a puppy moves from the breeder to a new home, new food is introduced): a probiotic course beforehand and during the transition can help the gut adapt. - When traveling or in other stressful situations proactively: probiotics can be given a few days before and throughout the stress period to support the gut, even if the dog is healthy (this is commonly used, for example, by dogs traveling to dog shows). - The dog tends to eat everything outside (e.g., feces, carcasses): continuous "germ exposure" can lead to recurrent loose stomach issues in some – in such cases, a daily prebiotic fiber supplement can help stabilize gut function, and probiotics can be used in courses as support. - Senior dog: in older dogs, prebiotics can support a declining microbiota and probiotics can boost immunity.

So, for a generally healthy, asymptomatic dog, there is no automatic need to provide supplements for the gut. Good food and a good life are sufficient. However, if you know a change is coming or want to ensure gut well-being in a particular situation, you can cautiously try probiotics or additional fiber. Always monitor your dog's reaction: for example, if starting probiotics worsens stool quality (rare, but individual differences exist), discontinue use.

Moderation is possible – but effectiveness varies. Yogurt, buttermilk, and kefir contain lactic acid bacteria that are probiotic for humans. For some dogs, a small amount of plain yogurt daily is beneficial: they receive both probiotics and prebiotic lactose (which their gut bacteria can use if the dog tolerates lactose). NOTE: However, many adult dogs do not tolerate lactose, so dairy products can cause loose stools. Therefore, it is advisable to test cautiously: a teaspoon of yogurt added to food and observe if symptoms occur. If not, the amount can be slightly increased. Dairy products more suitable for dogs are low-lactose or lactose-free versions (e.g., low-lactose buttermilk). Kefir has sometimes been praised because it contains several beneficial bacterial strains; a small splash can introduce good microbes. However, remember that probiotics from dairy products do not necessarily colonize the dog's gut permanently – they may provide temporary relief but do not replace the dog's own strains.

Another option is to give the dog small amounts of sauerkraut or kimchi if they like it (and if kimchi, then without onions/spices). Sauerkraut juice contains lactic acid bacteria and fiber, so some use it as a natural probiotic for dogs. Here too, a small dose is important: too much sauerkraut can cause flatulence.

As a general guideline: Yes, a dog can get lactic acid bacteria through food, but it is often safer for the stomach to use probiotics designed for dogs when a therapeutic effect is really desired (e.g., in cases of diarrhea). Yogurt can be given as a treat if the dog enjoys it and it suits them, but it is not advisable to force dairy products on a dog "for health reasons" if they do not want them or they do not suit.

Numerous studies have been conducted on prebiotics and probiotics for dogs, and many of them indicate benefits – provided the right strains and conditions are used. For example, probiotics have been shown in studies to: - Shorten the duration of acute, mild diarrhea in dogs by about one day on average compared to placebo[44]. - Reduce diarrhea during antibiotic treatment (in one experiment, an Enterococcus faecium probiotic reduced the incidence of antibiotic-associated diarrhea in puppies). - Improve stool quality in puppies and reduce diarrhea during the puppy period when added to food at the breeder. - Possibly alleviate symptoms of certain skin problems (there is evidence that certain probiotics reduce itching in atopic skin by modulating the immune system)[30]. - Improve the integrity of the intestinal mucosa, for example in stress situations (in laboratory animals it has been shown that probiotics can reduce "leaky gut" caused by stress hormones).

Evidence for prebiotics includes, among others: - Adding inulin and FOS to dog food increased bifidobacteria counts and improved stool consistency[22]. - In dogs prone to hard stools, psyllium fiber (ispaghula seed) added to the diet appropriately softened the stool. - Prebiotics can improve mineral absorption (in humans and likely in dogs as well, calcium absorption from the gut is enhanced when fermentable fibers are available). - In some studies, prebiotics have reduced the concentrations of harmful metabolic products (e.g., ammonia) in stool, thus making the gut environment "cleaner."

Postbiotics are a newer research subject, but some studies show that: - Postbiotic (e.g., fermented yeast cell wall) added to dog food reduced inflammatory markers in senior dogs and improved certain immune system parameters[45]. - A combination of postbiotics with prebiotics improved the amounts of Lactobacillus bacteria in old dogs and increased the production of beneficial fatty acids in the gut[46].

Overall, science supports that yes, these are beneficial, but the effects are often modest, meaning reasonably small and individual. They are not miracle cures that solve all problems, but they can be a valuable part of treatment or prevention. It is important to choose the right product and use it correctly. For example, if a dog has enteritis, a probiotic alone may not be sufficient to cure it, but it can support other treatments and speed up recovery.

Also, how clearly the benefit is noticed depends on the starting situation. A healthy dog may not "change" visibly upon starting a probiotic – which is to be expected, since it had no problem to begin with. But a dog with a sensitive stomach may clearly get a stronger stomach with the probiotic. So anecdotes vary, and science provides the average: there is benefit when the product and the situation meet.

There can definitely be a connection. In recent years, it has been understood that in many skin problems and allergies, the gut microbiome also plays a role. A common condition in dogs, called atopy (allergic itching), is an immune system disorder. And since a large part of the immune system is in the gut, it is logical that gut balance affects skin condition as well. One study found that atopic dogs had fewer certain beneficial bacteria and more inflammation-promoting bacteria in their gut compared to healthy dogs. When these atopic dogs were given postbiotics and prebiotics, some inflammatory markers in the skin decreased[30]. Yeast infections on the skin or in the ears can also be related to the gut: if antibiotics or diet cause dysbiosis in the gut, it is believed to predispose to yeast overgrowth not only in the gut but also on the skin, because the balance of immune defense is disrupted.

On the other hand, in dogs with severe food allergies, the gut often reacts first – vomiting or diarrhea – but the skin can also show symptoms (itching, redness). When gut health is improved (e.g., with an allergy diet, gut protectants, probiotics), skin symptoms often ease as well. This holistic concept is called the "gut-skin axis."

One should not forget the condition of the coat either: the absorption of nutrients (such as fatty acids, zinc, biotin) requires a healthy intestine. If the gut is in poor shape, deficiencies in vitamins and trace elements can be reflected in the skin and coat as roughness, dandruff, or hair loss.

Overall, if your dog has chronic skin problems or allergies, it is worth considering gut health as well. Often, fatty acid supplements (which also affect the gut) are used in the treatment of skin problems, and sometimes probiotics are also used to support immunomodulation. Even if the actual problem is in the skin (e.g., an allergic reaction to pollen), a healthy gut microbiota supports the dog's overall well-being and can help moderate excessive immune reactions. So yes, gut and skin health are surprisingly closely linked.

The first step is to identify if there is a need to improve something. If your dog is well, the gut microbiota is best maintained by keeping routines and feeding on point (see tips from the previous chapter). However, if you suspect that the dog's microbiome is not in optimal condition – for example, recurring stomach symptoms, the dog has had many antibiotic courses, or perhaps a rescue dog with a background of poor nutrition – you can take action:

1. Improving the diet: Possibly switch from low-quality food to one that is more digestible and nutritious. Add fiber in moderation, for example by mixing a spoonful of cooked pumpkin or carrot puree into the food (if the dog likes it), or occasionally offer the dog some steamed broccoli pieces as a treat. Fiber is fuel for good bacteria.
2. Prebiotic supplement: You can obtain prebiotic powder (e.g., FOS-inulin mix) from a pharmacy or animal clinic and add it to the food according to instructions. Start with a small dose and increase slowly so the dog gets used to it. This helps feed beneficial microbes and increase their proportion.
3. Probiotic course: Give the dog a reliable probiotic product, for example, a 1–2 month course. Especially if there has been antibiotic use or prolonged diarrhea, probiotics help restore balance. Remember to choose a product with bacterial strains suitable for dogs and that has been stored properly (so the bacteria are alive).
4. Limit unnecessary medications and chemicals: For example, if the dog often receives antibiotics, discuss with the veterinarian whether all those times were necessary or if there are alternatives. Similarly, continuous use of anti-inflammatory painkillers can disturb the gut – try to use medications only as needed and with protective medication if they irritate the stomach.
5. Give it time and avoid rushing: Improving the microbiome does not happen overnight. When you make good changes, continue them consistently. Avoid making too many changes at once so you know what works. For example, if you gave a probiotic and changed the food at the same time and the dog gets upset, you won't know which was the cause. One change at a time, a week or two of monitoring, then the next.
6. Diversifying the environment: This may sound funny, but according to some studies, dogs living in rural or natural settings have a more diverse skin and gut microbiome than those living entirely in the urban asphalt jungle. If possible, regularly take your dog to the forest or the edge of a field to sniff and romp around. This exposes it to "good dirt microbes." Of course, ensure tick protection and that it does not eat anything dangerous – the goal is not to get sick, but simply to let nature do its job in developing immunity.
7. Monitor and test if necessary: If you want to delve deeper, some specialized laboratories offer microbiome analysis from a dog's stool sample. This is not yet routine care and may not be cheap, but you get an accurate picture of which bacteria are present in the dog's gut and in what proportions. This allows you to target improvements – for example, if the analysis shows an overgrowth of proteobacteria, you would know that a very gentle diet and perhaps additional prebiotics are needed. However, for most, this is not necessary; basic methods will get you far.

Overall, improvement occurs by taking care of the basics: nutrition, exercise, low stress, and gut-friendly supplements if needed. The gut microbes will reward you – you will likely see changes in the dog's stool (firmer, less odor), skin (less itching, better coat), and general vitality over time.

The dog's digestive system has both similarities and differences compared to humans. Similarities include the basic structure (stomach, small intestine, large intestine) and the fact that both have a rich gut microbiota that affects health. Most of the same major groups of bacteria (Firmicutes, Bacteroidetes, etc.) inhabit the guts of both[11]. However, a major difference is that the dog is an omnivore whose digestion has evolved to process a meat-based diet. The dog's gut is relatively shorter than a human's, and the stomach is much larger and more acidic – dogs can digest, for example, raw bones and bacteria-rich meat better than humans. The pH of a dog's gut is lower (more acidic) to kill bacteria present in prey. The transit time is also faster: dog food passes through the intestines in about 12–30 hours, whereas in humans it can take 24–72 hours. This also affects the microbiome: Fusobacterium bacteria, which break down proteins, are more common in dogs than in humans[47], while in humans, abundant fiber fermentation produces many bacteria of the Bacteroides and Prevotella genera, which dogs have somewhat less of. Dogs are also better able to utilize animal fats and proteins as energy sources; their pancreas produces abundant protease enzymes for breaking down meat.

Practically, this is seen, for example, in the fact that foods that are healthy for humans (such as a very fiber-rich bean stew) can be too difficult to digest for dogs and cause flatulence, because their gut is not as long to ferment all the fiber completely. On the other hand, a dog can eat raw meat without stomach illness, whereas for a human it could be a risk – thanks to the dog's stomach acid and short intestine, bacteria do not have time to multiply to harmful levels, if the food is intended for the dog's own feeding use.

The role of the gut microbiome is probably very important for both species, but microbiome research in dogs is a younger field of science. One difference has been observed in immunological regulation: the microbes in dogs' intestines strongly affect, for example, their skin diseases, whereas in humans the gut has a significant impact on metabolic diseases. These differences may be due to both genetics and diet.

In summary: The dog's gut is designed from slightly different premises than a human's, but for the well-being of both, a diverse microbiome is beneficial. Many health tips for humans apply to dogs (fiber, fermented foods, stress management), but the dose and implementation must be adapted to suit the dog. Additionally, there are many individual differences among dogs – one should always recognize the special characteristics of their own pet, because some dogs digest even their shoes by eating everything, while others get an upset stomach from just half a sausage.

In conclusion: Canine gut health and microbiome balance are essential parts of your pet's well-being. So keep the gut as a friend – when you take care of food, routines, and love, your dog will thank you with a healthy, happy demeanor and a lively wagging tail. Caring for the gut is both preventive healthcare and a daily expression of love for your best friend. Well stomachs ahead to new adventures!

Sources:

[1][2]Tassu Foods blog: "The gut is your dog's immunological powerhouse", 23.1.2025 – Definition of the microbiome, the role of beneficial bacteria in digestion and immunity, the immune system's role in the gut.

[3]Bonel-Ayuso et al. 2025 (MDPI Microorganisms): Effects of Postbiotic Administration on Canine Health – Composition of the canine microbiome and its effects on digestion, vitamin synthesis, immune response, and pathogen defense.

[4]Kim et al. 2025 (BMC J. Animal Sci. & Biotech.): Understanding the diversity and roles of the canine gut microbiome – Microbial health effects: the gut microbiome regulates digestion, immune response, energy expenditure, and even behavior.

[5]Pellowe et al. 2025 (Scientific Reports): Gut microbiota composition is related to anxiety and aggression in dogs – Research finding: association of certain bacteria with anxiety and aggression in dogs, exemplified by the link between the genus Blautia and dog behavior.

[6]Kim et al. 2025 – A balanced microbiome (eubiosis) promotes health and metabolism, whereas microbiome imbalance (dysbiosis) has been linked to weight fluctuations, metabolic diseases, and behavioral changes.

[7]Kim et al. 2025 – Puppy gut phase: lactic acid bacteria from the mother's milk increase Firmicutes, Bacteroidetes, and Actinobacteria groups, which support the puppy's digestion and immune development.

[8]Kim et al. 2025 – Effect of age on the microbiome: bacterial diversity increases during puppyhood and stabilizes in adulthood; in older dogs, diversity may decline, which can impair digestion and immune defense.

[23]Kim et al. 2025 – Diet is the most significant factor affecting the microbiome; the protein and carbohydrate content of the diet shapes the composition of the gut bacterial community.

[22]Kim et al. 2025 – Effect of prebiotics: FOS and inulin increased SCFA production and the amount of beneficial bifidobacteria and Faecalibacterium genus bacteria in dogs.

[26]Kim et al. 2025 – Effect of fiber supplement (potato fiber): increased the proportion of Firmicutes bacteria and reduced Fusobacteria group bacteria, improving gut microbial balance.

[40]Kim et al. 2025 – Maintaining balance: optimizing diet according to life stage (protein, fiber, carbohydrates), including probiotics and prebiotics in the diet is essential, as they promote the growth of beneficial bacteria and the maintenance of eubiosis. Also, restoring beneficial microbes after antibiotics, minimizing stress factors, and environmental stability help maintain microbial balance.

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