Nurturing the microbiome

Sponsored by Hill's Pet Nutrition

Your pet's gut is teeming with life, a bustling metropolis of bacteria, fungi, and other microorganisms collectively known as the microbiome. A balanced microbiome benefits a pet directly-within the gut and indirectly-by impacting other systems or organs within the body. Within the gut, a healthy microbiome is essential for optimal digestion and nutrient absorption. Beneficial microbes in the gut ferment and digest fiber in your pet's food that would otherwise be excreted. This process ensures that pets absorb as many nutrients as possible from their food. A healthy microbiome also functions to enhance immune function and help regulate energy metabolism among others.^1,2,3 On the other hand, an imbalance in the microbiome, or dysbiosis, has been associated with multiple health conditions that affect multiple organ systems including chronic enteropathies, atopic dermatitis, chronic kidney disease, behavior and obesity to name a few.⁴ Here we'll explore nutritional solutions to foster a thriving microbiome in our dogs and cats.

Nutrition for a healthy microbiome

Probiotics: introducing beneficial bacteria

Probiotics are live microorganisms that may confer health benefits when consumed in adequate amounts. They can help restore balance in the gut microbiome, particularly after disruptions caused by antibiotics or illness. Probiotic supplements for dogs and cats typically contain strains of Saccharomyces, Lactobacillus, Bifidobacterium, and Enterococcus.⁵ These supplements can be found in various forms, including powders, capsules, and treats. Regularly incorporating probiotics into your pet's diet may potentially support digestive health, reduce gastrointestinal upset, and enhance immune function. Though promising, there are significant challenges associated with using probiotics. First, delivering live bacteria to the right part of the gut can be difficult. Depending upon the specific strain of bacteria and the form it’s being delivered in, the probiotic can be destroyed by the acidic environment of the stomach.⁶ Secondly, to be the most effective, the host the probiotic is derived from should be the same species as the recipient (i.e. a cat probiotic should be derived from cats).⁷ In this instance, the probiotics do not colonize in the gut and must be given consistently in order to maintain viable amounts of the bacterial species in the gut.⁸ Additionally, probiotics are not a one-size-fits-all option. Often, they are effective in one species or another or only under certain conditions. For example, one specific probiotic strain has shown efficacy in decreasing episodes of diarrhea in shelter cats, but the same effect was not seen in dogs.⁹ Other strains of probiotics have shown efficacy in improving gut flora and stool consistency in dogs with non-specific dietary sensitivities.¹⁰ Research of the use of probiotics in companion animal nutrition has shown some promising results but requires further investigation for targeted and sustained results.

Want to learn more about the microbiome? Check out dvm360's microbiome resource center here

Prebiotics: feeding the good bacteria

Prebiotics are non-digestible dietary fibers naturally found in fiber-rich foods such as fruits, vegetables, and whole grains, serving as nourishment for beneficial gut bacteria. Common prebiotics include beta-glucans, inulin, fructooligosaccharides (FOS), and galactooligosaccharides (GOS). When fermented and digested by the microbiome, these fibers yield end products that can positively impact pet health both directly within the gut and indirectly systemically. Prebiotics directly contribute to the growth and activity of beneficial bacteria already present in the gut, improve gut barrier function and improve stool quality and consistency.⁷ Indirectly, prebiotics have been shown to reduce inflammation, enhance immune response and improve mineral absorption.⁷ A recent literature review found that prebiotics benefit healthy adult and senior dogs by improving intestinal and immunological health.¹¹ Additionally, diets that contain prebiotic fiber bundles have been shown to help manage acute and chronic large bowel diarrhea¹², chronic kidney disease¹³, insulin sensitivity¹⁴ and anxiety.¹⁵

Use of prebiotics is not fraught with as many challenges as feeding probiotics, mainly because fibers are easily incorporated into pet foods, and all pets have bacteria and other microbes in their gut that will digest and ferment those fibers. The most frequent hurdle faced is identifying optimal ingredient amounts and identifying interindividual variability, which requires further research.⁷ However, even if the inclusion is not precisely optimized, prebiotics are functional foods and have been shown to be safe and effective for supporting overall gut health.¹⁶

Endogenous postbiotics: harnessing microbial metabolites

Endogenous postbiotics are the bioactive compounds produced by microbes during fermentation and digestion in the gastrointestinal tract. These postbiotics are emerging as the primary driver behind the beneficial impact pro- and prebiotics have on gut and overall pet health. These metabolites include short-chain fatty acids (SCFAs), enzymes, peptides, and vitamins. For example, SCFAs are a potent “food” for colonocytes within the gut. When the colonocytes have the nutrition they require, the mucosal layer is more robust, and the cell junctions are tighter, which promotes a healthier gut that is better able to absorb nutrients from food for the pet. Other postbiotics, like enzymes, peptides, and vitamins, have anti-inflammatory, antioxidant, and immunomodulatory effects.¹⁷ A recent study sought to determine the impact of supplementing postbiotics on health markers in beagle dogs. The results showed that postbiotic supplementation reduced serum triglyceride levels, cholesterol levels, uric acid levels and circulating inflammatory markers.¹⁸ The supplementation also increased the relative abundance of beneficial bacteria and reduced the relative abundance of harmful bacteria, indicating improved intestinal health in dogs.¹⁷ Though the study had a relatively small sample size (12 dogs), the research shows promise in future exploration of postbiotic supplementation.

It All Begins in the Gut

A well-nourished microbiome is the cornerstone of a pet’s overall health. Understanding the importance of the microbiome and incorporating appropriate nutritional solutions such as prebiotics, probiotics, and postbiotics, is a proactive way we can support the gut and overall health of dogs and cats.

Intended for Veterinary Professionals

References

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2. Tedelind, S.; Westberg, F.; Kjerrulf, M.; Vidal, A. Anti-inflammatory properties of the short-chain fatty acids acetate and propionate: A study with relevance to inflammatory bowel disease. World J. Gastroenterol. 2007, 13, 2826.
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