In recent years, the microbiome—the diverse community of microorganisms living in and on animals and humans—has emerged as a powerful influencer of health and disease. While much research has traditionally focused on the human microbiome, recent efforts have expanded to understand how the microbiome functions within pets, including cats and dogs. Curtis Huttenhower, PhD, a professor at Harvard’s T.H. Chan School of Public Health, is at the forefront of this exploration. At a recent Hill’s Symposium, he shared his insights on how microbiome research is shaping the future of veterinary medicine and beyond.

 

Bridging Human and Pet Health: Why Study the Microbiome in Pets?

Huttenhower’s motivation to explore the gut microbiome of pets was personal. What began as a passion project quickly evolved into groundbreaking research with broader implications for both animal and human health. By studying pets’ microbiomes, researchers can learn about diseases and health conditions specific to animals, such as chronic kidney disease in older cats, which may be influenced by kidney-damaging toxins from the microbiome. Targeting the microbiome with the right diet may help mitigate such risks, potentially extending pets’ lives and improving their quality of life.

Moreover, companion animals, who often consume highly controlled, monotonous diets, provide researchers with a unique opportunity to study specific interactions between diet and microbial responses.

 

Research insights can be valuable for understanding diet-related health factors in both pets and humans, as pets’ microbiomes offer clues to improving dietary recommendations for people.

 

The Hill’s x Harvard Partnership: Advancing Nutrition and Microbiome Research

One of the most promising collaborations in veterinary microbiome research is the partnership between Hill’s Pet Nutrition and Harvard University. Hill’s Pet Nutrition Center boasts facilities where approximately 450 dogs and 450 cats are monitored under carefully controlled conditions. This center enables researchers to refine nutrient levels in pet food products while studying the effects of diet on the microbiome. The facility’s high level of control allows Hill’s and Harvard researchers to track each pet’s food intake, collect stool samples, and analyze microbial DNA and metabolites with unparalleled precision.

 

“Some dogs could ferment the same fiber more efficiently than others, just because of different microbes that happened to have taken up residence in their guts,” Huttenhower noted. This variance in microbial fermentation may influence aspects of weight management and healthy aging, which are essential both for animals and humans. Understanding these microbial differences is a significant step toward designing personalized nutrition that could benefit both pets and people.

 

The Role of Fiber in Microbiome Health

Fiber’s importance in diet has been recognized for years, but its role in supporting the microbiome is now under closer scrutiny. Recent studies have explored how different types of fiber affect gut microbes in pets. Foods with various fiber compositions—from corn starch to pea fiber—showed surprising results: even in controlled settings, pets’ gut microbes produced distinct chemicals during digestion. These findings mirror research in humans, where high-fiber diets’ health benefits, including inflammation reduction and heart health, depend heavily on individual microbiomes.

 

These studies highlight a theme in modern microbiome research: microbes act as “little bags of chemistry” that perform unique and complex metabolic functions. This complexity explains why different individuals may respond to the same diet or medication differently based on their microbiomes. By decoding these microbial processes, researchers aim to create dietary guidelines and therapies tailored to individual needs, whether for pets or people.

 

One Health and the Microbiome: The Interconnectedness of Species

 

The concept of “One Health,” championed by the World Health Organization and other public health bodies, underscores the interconnectedness of human, animal, and environmental health. Huttenhower’s work exemplifies this principle, as he explores the potential transfer of microbes between pets and humans. For example, exposure to pets in early childhood may help lower the risk of allergies and immune disorders by introducing beneficial microbes that support immune development. Yet, there are potential risks as well. Because antibiotics are used more widely in veterinary medicine, antibiotic-resistant microbes could develop in pets and, theoretically, transfer to humans.

 

Ongoing research by Huttenhower and colleagues is examining these microbial exchanges between pets and owners, aiming to understand how shared microbes impact immune and metabolic health. “The connections between pet and human health reflect the One Health initiative…human, animal, and environmental health are all inextricably interrelated,” he said.

 

 

For veterinarians, the take-home message from Huttenhower’s research is simple: the microbiome plays a crucial role in their pet’s health, and maintaining it involves daily decisions like diet quality and responsible antibiotic use. “Small, daily decisions can have a lasting impact on a pet’s microbiome,” he advised.

 

Veterinarians are encouraged to stay informed about the growing body of microbiome research, especially as it continues to yield new insights relevant to animal health. While more research is needed before issuing definitive guidelines, veterinarians can already consider microbiome health when making dietary and treatment recommendations for their patients.

 

The Path Forward: Microbiome Research and Its Future Impact

 

As Huttenhower pointed out, the field of microbiome research is still in its infancy, with many questions yet to be answered. Hill’s and Harvard’s collaborative work has paved the way for understanding how microbes affect both animal and human health, and ongoing studies promise further revelations. Through efforts like the One Health Microbiome Resource (OHMR), researchers are building cross-species databases that will inform future studies on how microbiomes contribute to health across species.

 

“What I hope we gain with multi-species microbiome research is a deeper understanding of how microbial communities influence health across the animal kingdom,” Huttenhower stated.

 

The future of microbiome research is promising, offering veterinarians and pet owners new tools to promote pet health while advancing our understanding of health across species. As Huttenhower’s work shows, the microbiome’s influence extends far beyond our initial understanding, representing a frontier with the potential to transform veterinary and human medicine alike.