Probiotics For Dogs: The Ultimate Guide

probiotics for dogs

Few other supplements can have such a large impact on the immune system and health as probiotics for dogs. Gut bacteria play a large role in health and disease, so it’s important to support your dog’s microbiome by using the right probiotics at the right times.

What Is The Microbiome?

Bacteria live in all parts of your dog’s digestive tract. There are just a few that live in the stomach … but as you travel down the intestines, the numbers of bacteria increase. But by far the greatest number of bacteria live in your dog’s colon. 

The complex community of bacteria and other microorganisms in your dog’s gut is called the microbiome. These bacteria all function together and they work just like any other organ. In fact, scientists call the microbiome “the forgotten organ.” Each microbiome is unique to each dog, just like a fingerprint. That’s because every dog is exposed to a unique environment and diet.

RELATED: Learn more about your dog’s microbiome …

What Are Probiotics?

Probiotics for dogs are live organisms that provide health benefits. These good bacteria are found in your dog’s gut, in fermented foods and in supplements. Certain yeast species are also considered probiotic.

Beneficial bacteria have a few key jobs in your dog’s body. They help:

  • Promote overall dog gut health
  • Digest food
  • Produce key vitamins (including vitamin K and B vitamins)
  • Produce serotonin and influence mood
  • Reduce the gut pH
  • Crowd out harmful bacteria
  • Produce enzymes
  • Produce fatty acids that discourage the growth of harmful bacteria
  • Support the immune system

How Probiotics Support The Immune System

Bacteria like to live in your dog’s gut because they eat the same foods he does (or more exactly, they ferment food). Bacteria especially love to eat fiber because your dog can’t digest it. When bacteria eat fiber, they “poop out” short chain fatty acids (SCFAs). So probiotics for dogs are a great way to get more healthy SCFAs into your dog. The three main SCFAs are:

  • Acetate
  • Proprionate
  • Butyrate

Short chain fatty acids either remain in your dog’s colon or they travel into your dog’s body. Either way, they play a critical role in your dog’s health and immunity. They can:

  • Feed friendly bacteria and discourage the growth of harmful bacteria
  • Help form the protective mucus layer in the gut 
  • Keep the cells lining the gut close together (they prevent leaky gut)
  • Reduce glucose levels, which protects against metabolic disease and obesity
  • Build important T-cells in the immune system, which helps reduce chronic inflammation.
  • Protect against food allergens
  • Help the body absorb calcium, magnesium, iron and other nutrients

Since 80% of your dog’s immune system is in his gut, bacteria are critical to your dog’s health. Specifically, a diverse and well-populated bacteria population is critical to your dog’s health …

The Health Benefits Of Probiotics For Dogs

Because friendly bacteria support your dog’s immune system, most dogs can benefit from probiotics. But there are a wide variety of health issues that can be helped by probiotics:

  • Leaky gut
  • Yeast overgrowth
  • Urinary tract infections
  • Diarrhea
  • Colitis and bowel diseases
  • Pancreatitis
  • Obesity
  • Allergy symptoms
  • Mood disorders

Small changes to the species of bacteria living in your dog’s gut can have a noticeable impact on their host. The above diseases are all linked to shifts in the bacterial populations in your dog’s microbiome.

If your dog has a lot of diverse bacteria in his gut, these shifts are less significant. Large bacteria populations mean bacterial shifts will have a smaller impact on your dog’s health. But bacterial shifts happen all the time. Bacteria shifts can be caused by:

  • Antibiotics
  • Drugs
  • Toxins
  • Aging
  • A high starch diet 
  • A high fat diet

RELATED:  Find out how probiotics benefit your dog’s dental health … 

What Kind Of Probiotics Are Best For Dogs?

When you choose probiotics for dogs, the type you use really depends on his individual health and needs. Here are some of the best researched and most effective probiotic strains for dogs (and the amounts you should use).

Lactic Acid Probiotics

The vast majority of probiotics for dogs are lactic acid bacteria, usually made from fermented milk. You’ll see their strain names on the supplement label, along with the species name. The Bifidobacterium and Lactobacillus species are often shown as B. Or L. So you might see B. Longum or L. acidophilus

Lactobacillus species convert milk sugar to lactic acid, which inhibits the growth of harmful bacteria in the intestine. Like Lactobacillus, Bifidobacterium species produce lactic acid but they’re not considered a lactic acid bacteria. Bifidobacterium live in the colon and can interact with immune cells. They can crowd out harmful bacteria and help support the immune system. Low numbers of Lactobacillus and Bifidobacterium have been linked to anxiety.

Lactobacillus and Bifidobacterium probiotics are pretty fragile and they typically only last about 24 hours before they’re eliminated from the gut. But even though they’re unlikely to colonize, their DNA remains and they can still offer many health benefits. Overall, they’re useful probiotics for dogs with diarrhea.

Individual lactic acid probiotic strains include:

Lactobacillus Acidophilus
This is the tried and true bacteria found in most probiotics. It’s well researched in dogs and can increase Lactobacillus populations in the gut and reduce the populations of harmful clostridia. It also has a favorable effect on immune cells.

Lactobacillus Casei
This probiotic lives in the mucus membrane of animals. It’s an important part of the gut-brain axis and can affect mood and emotions.

Lactobacillus Plantarum And Lactobacillus Rhamnosus
These probiotics have been studied in dogs and have been shown to have a much better surviral rate. They help build healthy colon walls in dogs with IBS and can decrease antibiotic-related diarrhea. Low levels of Lactobacillus rhamnosus have been linked to anxiety in dogs.

Bifidobacterium Animalis
This probiotic has been found to be helpful for managing acute diarrhea in dogs.

Bifidobacterium Longum
This probiotic has been studied in dogs and is another one that works on the gut-brain axis. A study done by Purina found that larger numbers of Bifidobacterium longum can reduce signs of stress in dogs. B. longum can also help with diarrhea and food allergies.

Enterococcus Faecium
Enterococci are another lactic acid bacteria that inhibits the growth of harmful bacteria in the gut. This probiotic does a better job of surviving the acidity of the dog’s gut than most Lactobacillus and Bifidobacterium species. While this probiotic is healthy for dogs, it’s come under attack recently. Scientists are worried it can cause antibiotic-resistant enterococcal infections in humans. But it’s definitely beneficial for dogs and is a well-researched addition to canine probiotics.

Pediococcus Acidilactici
P. acidilactici is another lactic acid bacteria that’s showing a lot of promise in canine studies. It’s been successfully used to manage skin conditions and leaky guts.

Probiotic Yeast

Saccharomyces boulardii is a healthy yeast that’s in the category of probiotics for dogs. Saccharomyces boulardii is used to treat acute and chronic diarrhea in humans … and a recent trial in dogs showed the same benefits. S. boulardii has also been successfully used to treat Candida and yeast. S. boulardii also helps with digestive issues caused by chronic inflammation … it can alter cell signalling pathways in the immune system.

What’s unique about S. boulardii is that it can’t be killed by antibiotics. It can be taken at the same time as antibiotic use to help protect the beneficial gut bacteria and prevent antibiotic-related diarrhea. So this is one of the best probiotics for dogs on antibiotics.

Spore Forming Probiotics

Unlike Lactobacillus and Bifidobacterium, the Bacilli strains of probiotics are spore-forming. These bacteria can form a hard coating that protects them from heat, stomach acids and most antibiotics. In fact, many antibiotics are made from soil based probiotics for this reason.

Bacilli are also called soil based probiotics for dogs because they’re commonly found in soil and water. The most common strains used include:

Bacillus Coagulans
B. coagulans is a lactic acid producing bacteria, meaning it can crowd out unfriendly bacteria. Bacillus coagulans is also anti-inflammatory and can have a marked effect on inflammatory digestive diseases, which makes it a good probiotic for dogs with diarrhea. And a 2016 study also shows that it improved rheumatoid arthritis in rats. 

Bacillus Indicus
B. indicus is a unique probiotic … it produces large amounts of carotenoids. These are the yellow and orange pigments in plants. Carotenoids are powerful antioxidants. B. Indicus also produces B vitamins, vitamin K2 and quinols. This is an advantage for dogs with EPI and those needing digestive enzymes.

Bacillus Subtilis
B. Subtilis is an inhabitant in the guts of healthy dogs. It was used to treat urinary tract infections before antibiotics were developed. Like B. coagulens, B. subtilis has a strong influence on the immune system. It helps produce IgA, an antibody that’s often low in dogs with autoimmune disease. IgA bolsters the gut lining and also produces vitamin K.

Many Lactobacillus and Bifidobacterum probiotics are made from dairy, but S. boulardii and spore-forming probiotics aren’t. This makes them some of the best probiotics for dogs with allergies, especially dairy allergies.

Are There Natural Probiotics?

Bacteria ferment fiber and sugars … so they’re often found in foods. Common probiotic foods include:

Probiotic Yoghurt
Yoghurt is fermented milk made with the bacteria species Streptococcus thermophilus and Lactobacillus bulgaricus. There are a few problems with using yoghurt as a probiotic. First, dairy products can cause inflammation and immune issues in dogs. Second, most yoghurt contains very few probiotics. And most yoghurt is high in sugar, which can cause unwanted changes to the gut flora. 

Fermented Foods
Foods such as chaga, kefir and kimchi can be a healthy part of your dog’s diet. What’s unique about fermented foods is the extremely large number of prebiotics they contain. Prebiotics aren’t particular about the species of bacteria they feed, so fermented foods can potentially feed harmful bacteria and yeast. Fermented foods can also be a problem for dogs with SIBO (small intestinal bacterial overgrowth) and yeast infections, so use in moderation and with caution.

Prebiotic Foods
Foods that are high in fiber are the best choice to feed beneficial bacteria populations and support a healthy gut. Healthy prebiotic additions to your dog’s food include:

  • Mushrooms
  • Dandelion greens
  • Chicory root
  • Jerusalem artichoke
  • Garlic
  • Asparagus
  • Bananas

Choosing A Probiotic Supplement

The amount of probiotic you give your dog depends on the type of probiotic you choose. For the lactic acid bacteria, you’ll want to look for a supplement with several strains. Most studies on probiotics use a mix of strains because results with single strains aren’t as good. 

Because lactic acid bacteria are easily destroyed in the gut, you will need a product with a large number of colony forming units (CFU). You’ll usually want to see at least 10 billion CFU for any live probiotics to survive in your dog’s gut. This is fine for healthy dogs, but if your dog has digestive or immune problems, then look for about 25-50 billion CFU for a medium to large sized dog. Saccharomyces boulardii is much hardier than the dairy based probiotics, so a smaller amount can be given. In general, you can give a half billion to 5 billion CFU.

If you’re considering a spore forming dog probiotic, you can also use a smaller amount of CFUs because they easily survive the gut acidity. Look for about 1 billion CFU. 

Is it OK to give my dog probiotics daily?

Most dogs would do well with a daily probiotic, especially dogs eating kibble or a high starch diet. However, dogs with small intestinal bacterial overgrowth or dogs with excessive gas should not take probiotics daily.

What do vets say about probiotics for dogs?

Most vets are fine with giving dogs probiotics and many even sell them in their own clinics. They will usually just want you to give your dog a probiotic with well researched strains.

What kind of probiotics are best for dogs?

Soil-based probiotics are an excellent choice for dogs since they no longer eat off the ground and consume bacteria from the soil. These bacteria strains are also hardier and more likely to survive the dog’s harsh gut environment.

Do Probiotics Have Side Effects?

For the most part, probiotics for dogs are a completely safe supplement that have numerous safety studies. The most frequent side effects are digestive upset, gas and bloating.

The more frequently found issue with probiotics is that they don’t work. Here are some conditions where probiotics for dogs might not be the best approach to health:

Small Intestinal Bacteria Overgrowth (SIBO)

Most of your dog’s bacteria are meant to live in his colon. Small Intestinal Bacterial Overgrowth (SIBO) happens when abnormally large numbers of bacteria take up residence in the small intestine. These bacteria can interfere with digestion and nutrient absorption in the small intestine. SIBO can be caused by a few factors, including:

  • Diets that are high in sugar and carbohydrates
  • Reduced gut motility
  • Drugs that disrupt the microbiome (antibiotics and steroids)

It’s estimated that about 80% of people with chronic digestive issues actually have SIBO. And the number in dogs might be just as high.The symptoms of SIBO include:

  • Chronic or intermittent diarrhea
  • Weight loss
  • Gastresophophageal reflux disease (GERD)
  • Gas
  • IBS (or inflammatory bowel disease)
  • Food intolerances
  • Skin issues
  • Leaky gut

Because SIBO is an overgrowth of bacteria, giving your dog probiotics will be like adding fuel to the fire … depending on the probiotic. So if your dog’s symptoms get worse with probiotics, it could be a sign he has SIBO.

Spore forming (soil based) bacteria are a better choice if you suspect your dog has SIBO. These probiotics have a protective coating that allows them to stay in their spore state until their environment is safe. This allows them to pass through the small intestine and colonize in the colon. 

Probiotics And Dogs On Antibiotics

This one might surprise you! A 2018 study found that giving Lactobacillus probiotics after antibiotic use caused a delay in the microbiome’s recovery. And the recovery was less complete compared to the group where no probiotics were given. The best probiotics to help restore your dog’s microbiome after antibiotics are Saccharomyces boulardii and soil based probiotics (Bacillus subtiliis and Bacillus coagulans).

How Long Should Dogs Be On Probiotics?

If you’re giving probiotics for dogs as part of a preventative health plan, then you can give them most days. Soil based probiotics are typically a better choice for everyday probiotics since they are less likely to cause SIBO. 

If your dog has diarrhea, then a high CFU lactic acid probiotic should help within a few days. Some studies show that probiotics can cut the recovery time roughly in half. It’s best to continue the probiotics for a few weeks, to help resolve the underlying gut issues. 

If your dog has chronic diarrhea or a digestive disorder, then a good multi-strain probiotic with gut-soothing herbs is a good choice. In this case, you’ll want to keep your dog on the probiotics long-term or until the diarrhea completely resolves. 


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