Effect of Dietary Composite Probiotic Supplementation on the Microbiota of Different Oral Sites in Cats

Abstract

Probiotics demonstrated effectiveness in modulating oral microbiota and improving oral health in humans and rodents. However, its effects and applications on the oral microbiota of cats remain underexplored. Twelve healthy cats were randomly assigned to a control group (CON) and a composite probiotic group (CPG) for a 42-day trial. The CPG diet included additional supplementation of Bifidobacterium animalis subsp. lactis HN019, Lactobacillus acidophilus NCFM, and Lactobacillus casei LC-11, each at approximately 1 × 10¹⁰ CFU/kg. On days 0 and 42, microbial samples were collected from the gingiva, tooth surfaces, and tongue of all cats for 16S rRNA gene sequencing. Bacteroidetes, Firmicutes, and Proteobacteria were the dominant phyla across all oral sites. The CPG treatment enriched seven genera, such as Moraxella, Actinomyces, and Frederiksenia in the gingiva. Meanwhile, Bergeyella and Streptococcus were enriched on the tooth surfaces, while Bergeyella, Flavobacterium, and Luteimonas were enriched on the tongue. Furthermore, the composite probiotic effectively suppressed eight genera, such as Bacteroides, Desulfovibrio, and Filifactor in the gingiva of CPG cats, as well as Helcococcus, Lentimicrobium, and Campylobacter on tooth surfaces, and Porphyromonas, Treponema, and Fusibacter on the tongue. These findings suggest that the composite probiotic used in this study modulates the feline oral microbiota by supporting beneficial or commensal bacteria and inhibiting oral pathogens, demonstrating potential to improve oral health in cats.

Keywords: cat; gingiva; oral microbiota; probiotic; tongue; tooth surfaces.

Figure 1

Differences in α- and β-diversity of oral microbiota in cats at baseline. (A–F) Ace index, Chao index, Faith’s phylogenetic diversity, Simpson index, Shannon index, and Sobs index at the OTU level. (G–I) Principal coordinate analysis (PCoA) based on weighted UniFrac distance at the OTU level of cat gum, tooth surface, and tongue microbiota. CON, cats fed with a basal diet; and CPG, cats received the basal diet with a post-sprayed composite probiotic formulation. Values are mean ± SEM (n = 6).

Figure 2

Differences in α- and β-diversity of oral microbiota in different parts of cats on day 42. (A–F) Ace index, Chao index, Faith’s phylogenetic diversity, Simpson index, Shannon index, and Sobs index at the OTU level. (G–I) Principal coordinate analysis (PCoA) based on weighted UniFrac distance at the OTU level of cat gum, tooth surface, and tongue microbiota. CON, cats fed with a basal diet; and CPG, cats received the basal diet with a post-sprayed composite probiotic formulation. Values are mean ± SEM (n = 6).

Figure 3

Effects of different treatments on the composition of gingival microbiota in cats on day 42. (A,B) Community barplot analysis on the phylum and family levels. (C) Community heatmap analysis on the genus level. (D,E) Linear discriminant analysis effect size (LEfSe) analysis on the family and genus levels. CON, cats fed with a basal diet; and CPG, cats received the basal diet with a post-sprayed composite probiotic formulation.

Figure 4

Effects of different treatments on the composition of tooth surface microbiota in cats on day 42. (A,B) Community barplot analysis on the phylum and family levels. (C) Community heatmap analysis on the genus level. (D,E) Linear discriminant analysis effect size (LEfSe) analysis on the family and genus levels. CON, cats fed with a basal diet; and CPG, cats received the basal diet with a post-sprayed composite probiotic formulation.

Figure 5

Effects of different treatments on the composition of tongue microbiota in cats on day 42. (A,B) Community barplot analysis on the phylum and family levels. (C) Community heatmap analysis on the genus level. (D,E) Linear discriminant analysis effect size (LEfSe) analysis on the family and genus levels. CON, cats fed with a basal diet; and CPG, cats received the basal diet with a post-sprayed composite probiotic formulation.