Prebiotics & Probiotics

RFFDMSUK
Jul 26, 2024
6 min read

Updated: Feb 19

A Nutritional Guide to Prebiotics & Probiotics for Dogs

Prebiotics and probiotics are increasingly recognised for their role in supporting a balanced digestive environment. While probiotics introduce live cultures, prebiotics provide the fibres and compounds that help those cultures thrive. When used together, they can contribute to a varied, microbiome‑friendly diet for dogs.

This guide explains the difference between the two, highlights commonly used sources, and outlines how dog owners can incorporate them safely and responsibly.

1. Prebiotics vs. Probiotics: What’s the Difference?

Probiotics

Probiotics are live microorganisms—typically bacteria and yeasts—found naturally in fermented foods. They contribute to microbial diversity in the gut.

Prebiotics

Prebiotics are non‑digestible fibres and plant compounds that act as a food source for beneficial bacteria, helping them grow and remain active.

Why Both Matter

Probiotics rely on prebiotics to function effectively. Including both in a dog’s diet can help maintain a stable and diverse gut microbiome.

2. Prebiotic‑Rich Foods Commonly Used for Dogs

Because supplements vary widely in quality, choosing reputable, dog‑appropriate sources is important. Below are examples of prebiotic‑rich foods often used by dog owners.

Mushrooms

Such as Four Leaf Rover Seven 'Shrooms. This blend contains mushrooms naturally rich in beta‑glucans, fibre, and plant compounds that can help nourish beneficial gut bacteria.

This reference is educational only and not a therapeutic claim.

Organic Garlic (When Used Correctly and in Very Small Amounts)

Garlic contains inulin‑type prebiotic fibres, organo-sulphur compounds, and trace minerals.

Important Notes

Only organic raw white garlic should be used - see our blog highlighted above for guidance.
Chop or crush and allow a few minutes before feeding.
Feed sparingly — typically 1–2 times per week.

General Feeding Guidance

Dog’s Weight (kg)	Approx. Garlic Amount
4.5–9 kg	~½ clove
9–18 kg	~1 clove
20–32 kg	~2 cloves
32 kg+	~2½ cloves

For more detail, see your dedicated Garlic Blog.

Dandelion Greens

Dandelion greens contain inulin, fibre, vitamins A, C, K, and trace minerals. They are often used as a natural prebiotic source.

Ensure greens are free from pesticides.
Dandelion may increase urination due to its mineral content, so allow extra outdoor breaks.

Our Dandelion Blog details more information

Bone Broth

Bone broth contains gelatine, collagen, amino acids, and trace minerals. Bone broth is not a prebiotic in the strict sense, as it does not contain non‑digestible fibres. However, it provides gelatine, amino acids, and trace minerals that contribute to a supportive digestive environment and can be paired with prebiotic ingredients such as with small amounts of apple cider vinegar, it may also contain prebiotic compounds from plant additions.

Bone broth is widely used to add hydration and variety to meals.

3. Probiotic Sources Commonly Used for Dogs

Probiotics are live microorganisms that occur naturally in certain fermented foods or can be added intentionally through supplements. They contribute to microbial diversity in the gut and are widely used in canine nutrition. Below are the main categories of probiotic sources dog owners typically choose from, along with what makes each one unique.

A. Fermented Foods (Natural Dietary Sources)

Fermented foods contain live cultures produced during the fermentation process. These foods introduce a variety of bacteria and yeasts into the diet. Be careful that any options you use do not contain harmful ingredients like onion

Common Fermented Foods Used for Dogs

Kefir (milk or water‑based)
Fermented vegetables (dog‑safe options only, without onions or spices)
Certain mushroom ferments
Goat milk kefir (naturally lower in lactose)

Why They’re Used

Provide a broad spectrum of naturally occurring live cultures
Contain organic acids and enzymes created during fermentation
Offer dietary variety alongside a whole‑food diet

Because fermentation strength varies, especially in home-made or supermarket products, amounts should be introduced gradually.

B. Dog‑Specific Probiotic Products

These are formulated specifically for canine digestion and typically list the exact strains and quantities of live cultures. Examples are Alexanders Natural Kefir, Karnlea Goat Milk with added Pro & Postbiotics and Four Leaf Rover Pro-Biome

Examples of Dog‑Specific Probiotic Formats

Powders
Capsules
Chews
Freeze‑dried blends
Fermented dairy products made for dogs (e.g., dog‑specific kefir)

Why Owners Choose These

Clear labelling
Transparent ingredient lists
Formulated with canine digestion in mind

How to Choose the Right Type

When selecting a probiotic source, many owners consider:

Ingredient transparency
Strain diversity
Whether the product is dog‑specific
Dietary sensitivities (e.g., dairy‑free options)
Fermentation strength (for kefir and fermented foods)

Regardless of the source, probiotics should always be introduced gradually to assess tolerance.

4. Kefir vs. Yoghurt: What’s the Difference?

Although kefir and yoghurt are both fermented dairy products, they differ significantly in how they are made and the types of live cultures they contain. These differences influence how dog owners choose between them.

Kefir

Kefir is created by fermenting milk (or water) with kefir grains, which are a combination of bacteria and yeasts living in a symbiotic matrix. This fermentation process produces:

A broader range of live cultures than yoghurt
Naturally occurring organic acids and enzymes
A thinner, drinkable texture
Options in dairy (cow, goat, sheep) or non‑dairy (water kefir) forms

Because kefir grains contain multiple species of microorganisms, kefir tends to offer greater microbial diversity than yoghurt.

Yoghurt

Yoghurt is made by fermenting milk with a small number of specific bacterial strains, typically Lactobacillus bulgaricus and Streptococcus thermophilus. Compared to kefir, yoghurt:

Contains fewer live cultures
Often includes added sugars, fruits, or flavourings in supermarket versions
May be less suitable for dogs sensitive to dairy

Plain, unsweetened yoghurt can still be used in small amounts, but many owners prefer kefir due to its greater variety of naturally occurring live cultures and the availability of dog‑specific formulations.

5. Feeding Guidelines for Kefir

Kefir is a fermented food, so moderation is key. Dogs vary in how they tolerate fermented products, especially if they are new to them.

General Guideline

Up to 25 ml for dogs under 15 kg
Up to 50 ml for dogs 15 kg and above

How to Introduce It

Start with very small amounts (1–2 teaspoons)
Increase gradually over several days
Observe your dog’s digestion and comfort
Adjust the amount based on individual tolerance

Because fermentation strength varies between brands and homemade batches, these amounts are flexible starting points rather than strict rules.

6. Where to Buy Probiotics or Kefir

Dog owners have several options when choosing probiotic foods or supplements. Each option has its own considerations.

Supermarket Options

Plain, unsweetened kefir can be used, but:

Fermentation strength varies
Live culture counts may be lower than dog‑specific products
Always check for no added sugars, fruits, or flavourings

This can be a convenient option, but not always the most consistent.

Dog‑Specific Options

These products are formulated with canine digestion in mind and often use heirloom grains or clearly labelled probiotic strains.

Examples include:

Alexander’s Natural (dog‑specific kefir)
Boil & Broth (fermented products for dogs)
Four Leaf Rover Pro-Biome Soil‑based probiotic blend (spore‑forming bacteria)
Karnlea Goat’s Milk with Added Pro & Post Biotics

These mentions are educational only and not therapeutic claims. Owners often choose dog‑specific options for their ingredient transparency and consistent fermentation strength.