December 2, 2021

Get to know the bacteria living in your dog!

Usually we think of bacteria as just the things that get us sick.


Usually we think of bacteria as just the things that get us sick, and that we should try to clear out most bacteria. But the truth is that they play very important and beneficial roles in keeping people and dogs healthy. So it’s worth learning a bit about what they can do for us.

Most of the bacteria living in your dog’s gut are divided into five major groups: Bacteroidetes, Fusobacteria, Firmicutes, Actinobacteria, and Proteobacteria. Each group, or phylum (phyla in plural), includes hundreds or even thousands of known bacterial species found living in many environments. In the gut, the abundance of each phyla is closely related to what your dog eats on a daily basis.

This bacterial equilibrium is specific to each dog, and your dog’s health and well-being relies on the fine balance between the different types of bacteria. Stay’s seasonal microbiome checks (poop tests) give you a way to monitor your dog’s health from the inside. Our expert researchers and data scientists look at specific bacterial species and their influence on the gut, as well as other gut-health parameters.

Our goal is to understand which bacteria are living in each dog’s gut, how they are impacted by food, and what is the right diet that will help them make our best friends as healthy and happy as possible. Let’s start by introducing the “major five” phyla.


  • In the gut, Bacteroidetes specialize in breaking down large organic molecules like proteins and carbohydrates.
  • Bacteroidetes are important for your dog’s health, and studies have shown that dogs with chronic gut disease have fewer Bacteroidetes in their gut than healthy dogs.

Read more about Bacteroidetes and how it is affected by the dogs’ diet.


  • Fusobacteria is associated with healthy dogs and its population tends to decline in dogs suffering from gut disease.
  • At least one member of this phylum, Fusobacterium varium, breaks down proteins in the food and produces molecules important for the body.
  • Other members of this phylum, especially the species Fusobacterium mortiferum and Fusobacterium perfoetens, were found to be common in overweight dogs.

Read more about Fusobacteria and how it is affected by the dogs’ diet.


  • Many Firmicutes bacteria play an important role in the dogs’ gut by breaking down carbohydrates that can’t be digested by the body’s enzymes, such as dietary fiber and resistant starch. The byproducts of this process are molecules crucial for the dogs’ health.
  • Dogs with different types of gut disease tend to have low levels of bacteria from this phylum in their gut.
  • Research shows Firmicutes bacteria are also important to human health.

Read more about Firmicutes and how it is affected by the dogs’ diet.


  • In the gut, the overall impact of this diverse group of bacteria on dogs’ health is not completely understood, and research indicates they can have positive and negative impacts.
  • Dogs with high levels of Actinobacteria had higher levels of compounds related to good digestion.
  • Dogs suffering from joint diseases or sudden gut disorder had less Actinobacteria in their gut compared to healthy dogs.
  • Dogs suffering from a chronic gut disease had more Actinobacteria in their gut compared to healthy dogs.
  • Obese dogs were also found to have higher than typical levels of this phylum in their body.

Read more about Actinobacteria and how it is affected by the dogs’ diet.


  • Proteobacteria are less abundant than Firmicutes and Bacteroides, but have the largest variety of genes, allowing them to serve many different functions in the gut.
  • Some members of this group can be harmful to dogs, such as some members of the Enterobacteriaceae family that thrive at the expense of beneficial bacteria in the gut.
  • Dogs with chronic gut disease were found to have high levels of Proteobacteria in their gut.

Read more about Proteobacteria and how it is affected by the dogs’ diet.

Stay’s unique recipes are rich in a variety of digestible proteins, dietary fibers, and other nutrients specially designed to feed the different beneficial bacteria in your dog’s gut and sustain a healthy balance between the five common phyla.

Our biofeedback process and seasonal microbiome checks allow us to understand how nutrition is impacting this delicate balance, as well as specific important bacteria in each phylum, and make sure your dog’s food is meeting the needs of the beneficial bacteria in their gut.

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