271. Award Talk: Feeding Decisions That Matter: How Food Choices Shape Oral Health in Companion Animals.

Abstract Oral health is a fundamental component of overall health, yet periodontal disease remains a highly prevalent and underaddressed condition in both dogs and cats. Its development is driven by complex interactions among diet, oral microbiota, host immune responses, and feeding behaviors. As such, nutrition plays a central role in shaping the oral environment. This presentation synthesizes evidence from studies examining how diet format, functional ingredients, and dental chew strategies influence oral health outcomes and oral microbial ecology in companion animals. In cats, where routine oral hygiene practices are often difficult to implement, dietary interventions represent a practical approach to oral health management. Diet format influences oral indices and microbiota composition. Cats fed dry diets showed lower calculus and gingivitis scores, while wet-fed cats exhibited reduced supragingival bacterial diversity and enrichment of taxa commonly associated with periodontal disease. In contrast, dry-fed cats displayed microbial profiles more frequently associated with oral health, indicating that food texture and moisture content can influence plaque formation and microbial balance. Beyond diet format, functional ingredients offer additional opportunities to support feline oral health. Passive immunization using egg yolk IgY targeting Porphyromonas virulence factors resulted in reduced plaque accumulation in adult cats, highlighting the potential to modulate pathogenic mechanisms without relying solely on mechanical or chemical approaches. In dogs, studies demonstrate that dietary strategies, particularly the use of dental chews, can positively influence oral health. Daily administration of dental chews resulted in significant reductions in plaque and calculus accumulation, gingivitis, pocket bleeding, and halitosis compared with dogs consuming only diet. These clinical improvements were accompanied by beneficial shifts in the oral microbiota, characterized by reductions in potentially pathogenic taxa and enrichment of bacterial genera associated with oral health, supporting a preventive role. Diet format also influences canine oral health. Dogs fed dry extruded diets exhibited lower breath odor and trends toward reduced plaque accumulation compared with dogs fed wet canned diets. Microbial profiles in dry-fed dogs were more closely associated with oral health and showed lower abundances of recognized periodontal pathogens, reinforcing the importance of microbial outcomes. Characterization of oral microbial habitats further contextualizes these findings. Salivary, supragingival, and subgingival sites harbor distinct microbial communities, with plaque habitats being most relevant to periodontal disease. Although saliva is easy to collect, it does not accurately represent plaque microbiota linked to disease, emphasizing the importance of targeted sampling when evaluating dietary interventions. In conclusion, the collective evidence demonstrates that feeding decisions profoundly influence oral health in companion animals. Diet composition, physical form, and functional supplementation can shape oral microbial communities and support healthier oral environments. Integrating evidence-based nutritional strategies into oral health management provides a practical approach to move beyond reactive dental care toward proactive, lifelong oral health support.