How Raw Feeding Transforms Your Dog's Gut Microbiome
The emerging science of canine gut health and what it means for your dog
The gut microbiome — the complex community of trillions of bacteria, fungi, and other microorganisms living in the digestive tract — is now recognised as a central pillar of overall health in both humans and dogs. Research published over the past decade has established clear links between gut microbiome composition and immune function, inflammatory disease, mental health, and longevity. What your dog eats is the single most powerful determinant of their gut microbiome composition.
The Canine Gut Microbiome: A Primer
A healthy dog's gut contains approximately 100 trillion microorganisms from over 500 different species. The dominant bacterial phyla in healthy dogs are Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria, and Actinobacteria. The ratio and diversity of these communities is directly influenced by diet.
Microbial diversity is considered a key marker of gut health. Low diversity is associated with inflammatory bowel disease, obesity, allergies, and autoimmune conditions. High diversity is associated with resilience, efficient nutrient extraction, and robust immune function. Diet is the primary driver of this diversity.
What Raw Feeding Does to the Microbiome
A landmark 2017 study by Sandri et al., published in BMC Veterinary Research, compared the faecal microbiomes of dogs fed raw meat-based diets (RMBD) versus commercial kibble. The raw-fed dogs showed significantly higher abundances of Fusobacteria and Proteobacteria, and lower abundances of Firmicutes — a profile associated with more efficient protein fermentation and reduced carbohydrate fermentation.
A 2018 study by Schmidt et al. in PLOS ONE found that dogs fed BARF (Biologically Appropriate Raw Food) diets had significantly different faecal metabolomes compared to kibble-fed dogs, with higher concentrations of short-chain fatty acids (SCFAs) — particularly butyrate — which are the primary energy source for colonocytes (colon cells) and have potent anti-inflammatory effects.
Short-Chain Fatty Acids: The Gut Health Currency
Short-chain fatty acids (SCFAs) — acetate, propionate, and butyrate — are produced when gut bacteria ferment dietary fibre and protein. Butyrate in particular is critical for maintaining the integrity of the intestinal epithelium (the gut lining), regulating immune responses, and suppressing inflammatory pathways.
Dogs fed raw diets consistently show higher faecal butyrate concentrations than kibble-fed dogs. This is partly because raw diets contain more fermentable substrates (connective tissue, cartilage, organ meats) and partly because the different bacterial communities in raw-fed dogs are more efficient butyrate producers.
The Immune System Connection
Approximately 70–80% of a dog's immune system resides in the gut — in the form of gut-associated lymphoid tissue (GALT). The composition of the gut microbiome directly shapes the development and function of this immune tissue. Dysbiosis (microbial imbalance) has been linked to increased susceptibility to infection, autoimmune conditions, and chronic inflammation.
A 2021 review in Frontiers in Veterinary Science concluded that raw-fed dogs showed markers of reduced systemic inflammation compared to kibble-fed controls, including lower serum C-reactive protein (CRP) levels — a key marker of inflammation used in both human and veterinary medicine.
Transitioning to Raw: What to Expect
When transitioning from kibble to raw food, the gut microbiome undergoes significant restructuring. During the first 2–4 weeks, some dogs experience loose stools, increased flatulence, or changes in stool colour as the microbial community shifts. This is a normal adaptation response, not a sign that raw feeding is unsuitable.
A gradual transition over 7–14 days — replacing 25% of the current diet with raw food every few days — minimises digestive disruption. After the transition period, most dogs show firmer, smaller, less odorous stools — a reliable indicator of improved digestibility and reduced fermentation of undigested material.
Key Takeaways
- The gut microbiome is now recognised as central to immune function, inflammation, and longevity
- Raw-fed dogs show significantly higher microbial diversity than kibble-fed dogs
- Raw diets produce 3× higher faecal butyrate — a key anti-inflammatory compound
- 70–80% of the immune system resides in the gut, directly shaped by diet
- A 7–14 day gradual transition minimises digestive disruption when switching to raw
Feed the Microbiome That Feeds Your Dog
LUXE Pet Food's raw recipes include organ meats and connective tissue — the natural prebiotics that fuel a thriving gut microbiome.
References
- [1]Sandri M, Dal Monego S, Conte G, et al. (2017). Raw meat based diet influences faecal microbiome and end products of fermentation in healthy dogs. BMC Veterinary Research.DOI
- [2]Schmidt M, Unterer S, Suchodolski JS, et al. (2018). The fecal microbiome and metabolome differs between dogs fed Bones and Raw Food (BARF) diets and dogs fed commercial diets. PLOS ONE.DOI
- [3]Bermingham EN, Maclean P, Thomas DG, et al. (2017). Key bacterial families (Clostridiaceae, Erysipelotrichaceae and Bacteroidaceae) are related to the digestion of protein and energy in dogs. PeerJ.DOI
- [4]Wernimont SM, Radosevich J, Jackson MI, et al. (2020). The Effects of Nutrition on the Gastrointestinal Microbiome of Cats and Dogs. Frontiers in Microbiology.DOI