# Dual probiotic intervention with Lactiplantibacillus plantarum Kmiate-6 and Pediococcus acidilactici Kmiate-15 improves periodontal health and oral microbiota balance in dogs

## TL;DR

A dual probiotic treatment improved dog oral health by reducing plaque and inflammation while balancing the mouth's bacteria.

## Contribution

A novel dual probiotic combination was shown to effectively modulate canine oral microbiota and inflammation.

## Key findings

- The probiotic combination reduced dental plaque and plaque index in dogs after 21 days of administration.
- Probiotic treatment decreased pathogenic bacteria like Fusobacterium and Porphyromonas while increasing beneficial taxa.
- The intervention enhanced detoxification and antioxidation pathways while reducing reliance on vitamin biosynthesis pathways.

## Abstract

Periodontal disease is highly prevalent in dogs, yet current treatments such as dental scaling and antibiotics carry limitations including anesthesia risks, high recurrence, and antibiotic resistance. Probiotics have emerged as a promising strategy to modulate oral microbiota and host inflammation. This study evaluated the effects of dual probiotic intervention with Lactiplantibacillus plantarum Kmiate-6 and Pediococcus acidilactici Kmiate-15 on canine oral health through in vitro and in vivo assays.

Both strains exhibited antimicrobial activity against common oral pathogens, with Lactiplantibacillus plantarum Kmiate-6 showing stronger inhibition against Streptococcus mutans, Fusobacterium nucleatum, and Streptococcus mitis, while Pediococcus acidilactici Kmiate-15 demonstrated superior anti-inflammatory effects by reducing tumor necrosis factor-alpha and increasing interleukin-10 production. In vivo, 21-day oral administration of the probiotic combination significantly reduced dental plaque area and plaque index in dogs, along with decreased salivary tumor necrosis factor-alpha and elevated interleukin-10 levels. Microbiota analysis showed that probiotic intervention decreased the abundance of pathogenic genera such as Fusobacterium and Porphyromonas, and enriched beneficial taxa including Actinomyces and Weissella. Functional predictions based on 16S ribosomal RNA gene data indicated that probiotic treatment enhanced pathways related to detoxification, antioxidation, and propanoate metabolism, while reducing reliance on vitamin biosynthesis pathways typically exploited by pathogens.

Combined oral administration of Lactiplantibacillus plantarum Kmiate-6 and Pediococcus acidilactici Kmiate-15 effectively improved canine periodontal health by inhibiting plaque formation, modulating inflammatory responses, and reshaping oral microbial composition and function. These findings support the potential of probiotic-based strategies as safe and effective alternatives for maintaining oral health in dogs.

The online version contains supplementary material available at 10.1186/s42523-026-00524-1.