Dog Nutrition: Understanding Prebiotics and Probiotics
Published date: 15 August 2025
Prebiotics and probiotics are seen in lots of foods, treats and healthcare products, both in the pet and human industry.
However, these terms can be easy to mix up, and sometimes it’s not even clear what they do and how they benefit.
Prebiotics and probiotics support dog digestive health and promote healthy stools. So, let’s break down what each term means and why they are important.
What is a Probiotic?
Probiotics are the friendly bacteria which make up the gut microbiome.
These friendly microorganisms within the gut support your dog’s health. They break down (ferment) food in the large intestine, fight off bad bacteria, and nourish the intestinal system.
Supplementing with probiotics has become more popular recently and can be a brilliant way to strengthen your dog’s digestive health. Using probiotics alongside a prebiotic-rich diet is particularly helpful as the two work together to promote a harmonious gut environment.
What is a Prebiotic?
A prebiotic is a fibre which is not digested by the body. Instead, prebiotics travel to the large intestine, where they are converted into short-chain fatty acids (SCFA), providing a source of food for the friendly microbes (bacteria and fungi) in the gut.
Prebiotics feed and nourish the probiotics (friendly bacteria) that live in the large intestine. Some types of prebiotics also help prevent bad bacteria from sticking and growing within the intestinal tract. The healthier your dog’s gut microbiome is, the stronger their brain and digestive health.
Discover more about the connection between your dog’s gut and brain.
Prebiotics in Dog Food
Prebiotics are found in a diverse array of natural plant ingredients. They can also be added as supplements to diets. Look out for the following ingredients or terms on your dog’s food.
- FOS (sometimes listed as Fructooligosaccharides)
- MOS (sometimes listed as Mannan oligosaccharides)
- Chicory Root or Chicory Inulin
- Dandelion
- Banana
- Oats
- Apple
- Burdock Root
These can all be sources of prebiotics; however, typically, FOS & MOS are added to diets.
Some high-quality diets will include higher levels of prebiotics to better support the digestive system and promote healthier stools.
Does My Dog Need a Probiotic Supplement?
The following are possible signs that your dog’s gut microbiome is imbalanced and would benefit from additional supplementation.
- Loose stools
- Constipation
- Frequent flatulence
- Bad Breath (remember, dental disease is also common, so regularly check your dog’s teeth)
- Bloating
Some vets will recommend probiotic supplements after an illness, such as gastroenteritis, to replenish the good bacteria that were lost due to vomiting and diarrhoea.
If your dog has been on antibiotics, most of the bacteria in their gut have likely been killed off. For this reason, it is advised to begin using a prebiotic and probiotic supplement after the course finishes.
