ATLANTA — With pet parents seeking more functional nutritional products to support their barking and meowing companions, biotic ingredients have become all the rage. Known for the ability to support gut health in humans, biotics have proliferated the pet food industry for their purported benefits to the pet microbiome.

Kelly Swanson, Ph.D., director of the division of nutritional sciences at the University of Illinois Urbana-Champaign, took a deep dive into biotics during his presentation at the American Feed Industry Association’s 2024 Pet Food Conference, revealing potential benefits and applications in pet nutrition.

According to Swanson, gastrointestinal (GI) health can be defined by several factors including proper digestion and nutrient absorption, a stable and resilient microbiota, and a functional immune system. Typical indicators of GI health can range from a pet’s stool quality and immune markers to their response to health challenges.

The microorganisms in the gut play an imperative role in gut health, as well as a pet’s overall health, according to Swanson. These microorganisms help support gut immunity, energy, metabolism, resistance to pathogens and more. However, the industry’s understanding of the pet microbiome and gut health are just beginning. As demonstrated by Swanson, the view of cats’ and dogs’ microbiomes are continuing to evolve as additional microorganism strains and genes are discovered.

Many dietary strategies have emerged to help support GI health in pets, but the most common is the use of pro-, pre- and postbiotics.

The International Scientific Association for Probiotics and Prebiotics (ISAPP), a non-profit that seeks to promote the science behind these biotics, has come up with clear definitions for each. In accordance with the ISAPP, a biotic must demonstrate clear health benefits, which could be focused on the gut or elsewhere.



According to the ISAPP, a probiotic is a “live microorganism that, when administered in adequate amounts, confer a health benefit on the host.”

Common taxa of probiotics include Lactobacillus, Bifidobacterium, Bacillus and Enterococcus. These probiotics can be leveraged in many formats, including dry powders, gels and liquids, and even in pet diets, treats or toppers to provide health benefits.

According to Swanson, probiotics offer many benefits to pets, ranging from reduced diarrhea to management of chronic inflammatory bowel issues, by offering minor to moderate alterations to a pet’s gut microbiota. These particular biotics currently are the most researched and demonstrate some of the best health evidence, according to Swanson.



According to the ISAPP, a prebiotic is a “substrate that is selectively utilized by host microorganisms, conferring a health benefit.” Prebiotic substances can include phenolics and phytochemicals, oligosaccharides, conjugated linoleic acid (CLAs), and polyunsaturated fatty acids (PUFAs).

Regarding their benefits, prebiotics mainly help improve stool quality in pets but can also provide protection against pathogens. According to Swanson, use of these particular biotics often results in moderate to large shifts to the microbiome, demonstrating a more visible impact on a pet’s health.



A rather new term in the biotic world for the pet industry is synbiotic. According to the ISAPP, a synbiotic is a “mixture of live microorganisms and substrate(s) selectively utilized by host microorganisms that confers a health benefit.” This mixture could include pro- and prebiotics, or other live microorganisms.

Synbiotics can be complementary or synergistic, according to Swanson. Complementary synbiotics are made of a mixture of probiotics and prebiotics, with each working independently to provide one or more health benefits. Synergistic synbiotics are a mixture of a substrate and a live microbe that work together to provide a specific health benefit.



According to the ISAPP, a postbiotic is a “preparation of inanimate microorganisms and/or their components that confers a health benefit on the host.” Important to note here is that postbiotics are deliberately inactivated or killed. They could be any microorganism that offers a health benefit, but they must be purposely killed. Within this definition, Swanson clarified that vaccines, microbial metabolites and metabolites produced by gut microbiota are not considered postbiotics.

Postbiotics can provide a litany of benefits including maintaining stool quality, modifying gut microbiota, reducing fecal odor, increasing antioxidant capacity, and supporting the immune system. These biotics are relatively new to the pet space, but are gaining traction for their benefits, as well as their stability.

According to Swanson, many postbiotics are already approved by the Association of American Feed Control Officials (AAFCO), like yeast; are much more shelf stable and can withstand harsher processing compared to pre- and probiotics; and boast high palatability. However, despite their significant benefits and stability, very little research has been done on postbiotics.


The future of biotics 

As research on pet microbiomes and gut health continues, as will the research done on biotics. Swanson said he anticipates that the discovery of new microbes in the gut and advanced cultivation of biotics will fuel the category. Machine learning, robotics, and artificial intelligence (AI) are also expected to help support the future of biotics, as this technology could lend well to automizing the cultivation of more biotics.

Additionally, Swanson said he expects as the popularity of biotics continues, more novel sources, mixtures and delivery formats will need to be explored in order to keep pace with demand. Precise dosing and personalization will also play a factor as more personalized pet nutrition products hit the market. These will likely focus on species-specific biotics, as well as those for specific diets and microbiomes.

Though the biotics category in pet may only have just begun, Swanson emphasized the need for expanded research on new biotic strains and proper dosing to ensure benefits and safety.

Read more coverage from the 2024 Pet Food Conference